/* * Copyright (c) 2019, Alliance for Open Media. All rights reserved * * This source code is subject to the terms of the BSD 2 Clause License and * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License * was not distributed with this source code in the LICENSE file, you can * obtain it at www.aomedia.org/license/software. If the Alliance for Open * Media Patent License 1.0 was not distributed with this source code in the * PATENTS file, you can obtain it at www.aomedia.org/license/patent. */ /*!\defgroup gf_group_algo Golden Frame Group * \ingroup high_level_algo * Algorithms regarding determining the length of GF groups and defining GF * group structures. * @{ */ /*! @} - end defgroup gf_group_algo */ #include #include #include "aom_mem/aom_mem.h" #include "config/aom_config.h" #include "config/aom_scale_rtcd.h" #include "aom/aom_codec.h" #include "aom/aom_encoder.h" #include "av1/common/av1_common_int.h" #include "av1/encoder/encoder.h" #include "av1/encoder/firstpass.h" #include "av1/encoder/gop_structure.h" #include "av1/encoder/pass2_strategy.h" #include "av1/encoder/ratectrl.h" #include "av1/encoder/rc_utils.h" #include "av1/encoder/temporal_filter.h" #include "av1/encoder/thirdpass.h" #include "av1/encoder/tpl_model.h" #include "av1/encoder/encode_strategy.h" #define DEFAULT_KF_BOOST 2300 #define DEFAULT_GF_BOOST 2000 #define GROUP_ADAPTIVE_MAXQ 1 static void init_gf_stats(GF_GROUP_STATS *gf_stats); static int define_gf_group_pass3(AV1_COMP *cpi, EncodeFrameParams *frame_params, int is_final_pass); // Calculate an active area of the image that discounts formatting // bars and partially discounts other 0 energy areas. #define MIN_ACTIVE_AREA 0.5 #define MAX_ACTIVE_AREA 1.0 static double calculate_active_area(const FRAME_INFO *frame_info, const FIRSTPASS_STATS *this_frame) { const double active_pct = 1.0 - ((this_frame->intra_skip_pct / 2) + ((this_frame->inactive_zone_rows * 2) / (double)frame_info->mb_rows)); return fclamp(active_pct, MIN_ACTIVE_AREA, MAX_ACTIVE_AREA); } // Calculate a modified Error used in distributing bits between easier and // harder frames. #define ACT_AREA_CORRECTION 0.5 static double calculate_modified_err_new(const FRAME_INFO *frame_info, const FIRSTPASS_STATS *total_stats, const FIRSTPASS_STATS *this_stats, int vbrbias, double modified_error_min, double modified_error_max) { if (total_stats == NULL) { return 0; } const double av_weight = total_stats->weight / total_stats->count; const double av_err = (total_stats->coded_error * av_weight) / total_stats->count; double modified_error = av_err * pow(this_stats->coded_error * this_stats->weight / DOUBLE_DIVIDE_CHECK(av_err), vbrbias / 100.0); // Correction for active area. Frames with a reduced active area // (eg due to formatting bars) have a higher error per mb for the // remaining active MBs. The correction here assumes that coding // 0.5N blocks of complexity 2X is a little easier than coding N // blocks of complexity X. modified_error *= pow(calculate_active_area(frame_info, this_stats), ACT_AREA_CORRECTION); return fclamp(modified_error, modified_error_min, modified_error_max); } static double calculate_modified_err(const FRAME_INFO *frame_info, const TWO_PASS *twopass, const AV1EncoderConfig *oxcf, const FIRSTPASS_STATS *this_frame) { const FIRSTPASS_STATS *total_stats = twopass->stats_buf_ctx->total_stats; return calculate_modified_err_new( frame_info, total_stats, this_frame, oxcf->rc_cfg.vbrbias, twopass->modified_error_min, twopass->modified_error_max); } // Resets the first pass file to the given position using a relative seek from // the current position. static void reset_fpf_position(TWO_PASS_FRAME *p_frame, const FIRSTPASS_STATS *position) { p_frame->stats_in = position; } static int input_stats(TWO_PASS *p, TWO_PASS_FRAME *p_frame, FIRSTPASS_STATS *fps) { if (p_frame->stats_in >= p->stats_buf_ctx->stats_in_end) return EOF; *fps = *p_frame->stats_in; ++p_frame->stats_in; return 1; } static int input_stats_lap(TWO_PASS *p, TWO_PASS_FRAME *p_frame, FIRSTPASS_STATS *fps) { if (p_frame->stats_in >= p->stats_buf_ctx->stats_in_end) return EOF; *fps = *p_frame->stats_in; /* Move old stats[0] out to accommodate for next frame stats */ memmove(p->frame_stats_arr[0], p->frame_stats_arr[1], (p->stats_buf_ctx->stats_in_end - p_frame->stats_in - 1) * sizeof(FIRSTPASS_STATS)); p->stats_buf_ctx->stats_in_end--; return 1; } // Read frame stats at an offset from the current position. static const FIRSTPASS_STATS *read_frame_stats(const TWO_PASS *p, const TWO_PASS_FRAME *p_frame, int offset) { if ((offset >= 0 && p_frame->stats_in + offset >= p->stats_buf_ctx->stats_in_end) || (offset < 0 && p_frame->stats_in + offset < p->stats_buf_ctx->stats_in_start)) { return NULL; } return &p_frame->stats_in[offset]; } // This function returns the maximum target rate per frame. static int frame_max_bits(const RATE_CONTROL *rc, const AV1EncoderConfig *oxcf) { int64_t max_bits = ((int64_t)rc->avg_frame_bandwidth * (int64_t)oxcf->rc_cfg.vbrmax_section) / 100; if (max_bits < 0) max_bits = 0; else if (max_bits > rc->max_frame_bandwidth) max_bits = rc->max_frame_bandwidth; return (int)max_bits; } // Based on history adjust expectations of bits per macroblock. static void twopass_update_bpm_factor(AV1_COMP *cpi, int rate_err_tol) { TWO_PASS *const twopass = &cpi->ppi->twopass; const PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; // Based on recent history adjust expectations of bits per macroblock. double rate_err_factor = 1.0; const double adj_limit = AOMMAX(0.2, (double)(100 - rate_err_tol) / 200.0); const double min_fac = 1.0 - adj_limit; const double max_fac = 1.0 + adj_limit; if (cpi->third_pass_ctx && cpi->third_pass_ctx->frame_info_count > 0) { int64_t actual_bits = 0; int64_t target_bits = 0; double factor = 0.0; int count = 0; for (int i = 0; i < cpi->third_pass_ctx->frame_info_count; i++) { actual_bits += cpi->third_pass_ctx->frame_info[i].actual_bits; target_bits += cpi->third_pass_ctx->frame_info[i].bits_allocated; factor += cpi->third_pass_ctx->frame_info[i].bpm_factor; count++; } if (count == 0) { factor = 1.0; } else { factor /= (double)count; } factor *= (double)actual_bits / DOUBLE_DIVIDE_CHECK((double)target_bits); if ((twopass->bpm_factor <= 1 && factor < twopass->bpm_factor) || (twopass->bpm_factor >= 1 && factor > twopass->bpm_factor)) { twopass->bpm_factor = factor; twopass->bpm_factor = AOMMAX(min_fac, AOMMIN(max_fac, twopass->bpm_factor)); } } int err_estimate = p_rc->rate_error_estimate; int64_t total_actual_bits = p_rc->total_actual_bits; double rolling_arf_group_actual_bits = (double)twopass->rolling_arf_group_actual_bits; double rolling_arf_group_target_bits = (double)twopass->rolling_arf_group_target_bits; #if CONFIG_FPMT_TEST const int is_parallel_frame = cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0 ? 1 : 0; const int simulate_parallel_frame = cpi->ppi->fpmt_unit_test_cfg == PARALLEL_SIMULATION_ENCODE ? is_parallel_frame : 0; total_actual_bits = simulate_parallel_frame ? p_rc->temp_total_actual_bits : p_rc->total_actual_bits; rolling_arf_group_target_bits = (double)(simulate_parallel_frame ? p_rc->temp_rolling_arf_group_target_bits : twopass->rolling_arf_group_target_bits); rolling_arf_group_actual_bits = (double)(simulate_parallel_frame ? p_rc->temp_rolling_arf_group_actual_bits : twopass->rolling_arf_group_actual_bits); err_estimate = simulate_parallel_frame ? p_rc->temp_rate_error_estimate : p_rc->rate_error_estimate; #endif if ((p_rc->bits_off_target && total_actual_bits > 0) && (rolling_arf_group_target_bits >= 1.0)) { if (rolling_arf_group_actual_bits > rolling_arf_group_target_bits) { double error_fraction = (rolling_arf_group_actual_bits - rolling_arf_group_target_bits) / rolling_arf_group_target_bits; error_fraction = (error_fraction > 1.0) ? 1.0 : error_fraction; rate_err_factor = 1.0 + error_fraction; } else { double error_fraction = (rolling_arf_group_target_bits - rolling_arf_group_actual_bits) / rolling_arf_group_target_bits; rate_err_factor = 1.0 - error_fraction; } rate_err_factor = AOMMAX(min_fac, AOMMIN(max_fac, rate_err_factor)); } // Is the rate control trending in the right direction. Only make // an adjustment if things are getting worse. if ((rate_err_factor < 1.0 && err_estimate >= 0) || (rate_err_factor > 1.0 && err_estimate <= 0)) { twopass->bpm_factor *= rate_err_factor; twopass->bpm_factor = AOMMAX(min_fac, AOMMIN(max_fac, twopass->bpm_factor)); } } static const double q_div_term[(QINDEX_RANGE >> 5) + 1] = { 32.0, 40.0, 46.0, 52.0, 56.0, 60.0, 64.0, 68.0, 72.0 }; #define EPMB_SCALER 1250000 static double calc_correction_factor(double err_per_mb, int q) { double power_term = 0.90; const int index = q >> 5; const double divisor = q_div_term[index] + (((q_div_term[index + 1] - q_div_term[index]) * (q % 32)) / 32.0); double error_term = EPMB_SCALER * pow(err_per_mb, power_term); return error_term / divisor; } // Similar to find_qindex_by_rate() function in ratectrl.c, but includes // calculation of a correction_factor. static int find_qindex_by_rate_with_correction( int desired_bits_per_mb, aom_bit_depth_t bit_depth, double error_per_mb, double group_weight_factor, int best_qindex, int worst_qindex) { assert(best_qindex <= worst_qindex); int low = best_qindex; int high = worst_qindex; while (low < high) { const int mid = (low + high) >> 1; const double q_factor = calc_correction_factor(error_per_mb, mid); const double q = av1_convert_qindex_to_q(mid, bit_depth); const int mid_bits_per_mb = (int)((q_factor * group_weight_factor) / q); if (mid_bits_per_mb > desired_bits_per_mb) { low = mid + 1; } else { high = mid; } } return low; } /*!\brief Choose a target maximum Q for a group of frames * * \ingroup rate_control * * This function is used to estimate a suitable maximum Q for a * group of frames. Inititally it is called to get a crude estimate * for the whole clip. It is then called for each ARF/GF group to get * a revised estimate for that group. * * \param[in] cpi Top-level encoder structure * \param[in] av_frame_err The average per frame coded error score * for frames making up this section/group. * \param[in] inactive_zone Used to mask off /ignore part of the * frame. The most common use case is where * a wide format video (e.g. 16:9) is * letter-boxed into a more square format. * Here we want to ignore the bands at the * top and bottom. * \param[in] av_target_bandwidth The target bits per frame * * \return The maximum Q for frames in the group. */ static int get_twopass_worst_quality(AV1_COMP *cpi, const double av_frame_err, double inactive_zone, int av_target_bandwidth) { const RATE_CONTROL *const rc = &cpi->rc; const AV1EncoderConfig *const oxcf = &cpi->oxcf; const RateControlCfg *const rc_cfg = &oxcf->rc_cfg; inactive_zone = fclamp(inactive_zone, 0.0, 0.9999); if (av_target_bandwidth <= 0) { return rc->worst_quality; // Highest value allowed } else { const int num_mbs = (oxcf->resize_cfg.resize_mode != RESIZE_NONE) ? cpi->initial_mbs : cpi->common.mi_params.MBs; const int active_mbs = AOMMAX(1, num_mbs - (int)(num_mbs * inactive_zone)); const double av_err_per_mb = av_frame_err / (1.0 - inactive_zone); const int target_norm_bits_per_mb = (int)((uint64_t)av_target_bandwidth << BPER_MB_NORMBITS) / active_mbs; int rate_err_tol = AOMMIN(rc_cfg->under_shoot_pct, rc_cfg->over_shoot_pct); // Update bpm correction factor based on previous GOP rate error. twopass_update_bpm_factor(cpi, rate_err_tol); // Try and pick a max Q that will be high enough to encode the // content at the given rate. int q = find_qindex_by_rate_with_correction( target_norm_bits_per_mb, cpi->common.seq_params->bit_depth, av_err_per_mb, cpi->ppi->twopass.bpm_factor, rc->best_quality, rc->worst_quality); // Restriction on active max q for constrained quality mode. if (rc_cfg->mode == AOM_CQ) q = AOMMAX(q, rc_cfg->cq_level); return q; } } #define INTRA_PART 0.005 #define DEFAULT_DECAY_LIMIT 0.75 #define LOW_SR_DIFF_TRHESH 0.01 #define NCOUNT_FRAME_II_THRESH 5.0 #define LOW_CODED_ERR_PER_MB 0.01 /* This function considers how the quality of prediction may be deteriorating * with distance. It comapres the coded error for the last frame and the * second reference frame (usually two frames old) and also applies a factor * based on the extent of INTRA coding. * * The decay factor is then used to reduce the contribution of frames further * from the alt-ref or golden frame, to the bitframe boost calculation for that * alt-ref or golden frame. */ static double get_sr_decay_rate(const FIRSTPASS_STATS *frame) { double sr_diff = (frame->sr_coded_error - frame->coded_error); double sr_decay = 1.0; double modified_pct_inter; double modified_pcnt_intra; modified_pct_inter = frame->pcnt_inter; if ((frame->coded_error > LOW_CODED_ERR_PER_MB) && ((frame->intra_error / DOUBLE_DIVIDE_CHECK(frame->coded_error)) < (double)NCOUNT_FRAME_II_THRESH)) { modified_pct_inter = frame->pcnt_inter - frame->pcnt_neutral; } modified_pcnt_intra = 100 * (1.0 - modified_pct_inter); if ((sr_diff > LOW_SR_DIFF_TRHESH)) { double sr_diff_part = ((sr_diff * 0.25) / frame->intra_error); sr_decay = 1.0 - sr_diff_part - (INTRA_PART * modified_pcnt_intra); } return AOMMAX(sr_decay, DEFAULT_DECAY_LIMIT); } // This function gives an estimate of how badly we believe the prediction // quality is decaying from frame to frame. static double get_zero_motion_factor(const FIRSTPASS_STATS *frame) { const double zero_motion_pct = frame->pcnt_inter - frame->pcnt_motion; double sr_decay = get_sr_decay_rate(frame); return AOMMIN(sr_decay, zero_motion_pct); } #define DEFAULT_ZM_FACTOR 0.5 static double get_prediction_decay_rate(const FIRSTPASS_STATS *frame_stats) { const double sr_decay_rate = get_sr_decay_rate(frame_stats); double zero_motion_factor = DEFAULT_ZM_FACTOR * (frame_stats->pcnt_inter - frame_stats->pcnt_motion); // Clamp value to range 0.0 to 1.0 // This should happen anyway if input values are sensibly clamped but checked // here just in case. if (zero_motion_factor > 1.0) zero_motion_factor = 1.0; else if (zero_motion_factor < 0.0) zero_motion_factor = 0.0; return AOMMAX(zero_motion_factor, (sr_decay_rate + ((1.0 - sr_decay_rate) * zero_motion_factor))); } // Function to test for a condition where a complex transition is followed // by a static section. For example in slide shows where there is a fade // between slides. This is to help with more optimal kf and gf positioning. static int detect_transition_to_still(const FIRSTPASS_INFO *firstpass_info, int next_stats_index, const int min_gf_interval, const int frame_interval, const int still_interval, const double loop_decay_rate, const double last_decay_rate) { // Break clause to detect very still sections after motion // For example a static image after a fade or other transition // instead of a clean scene cut. if (frame_interval > min_gf_interval && loop_decay_rate >= 0.999 && last_decay_rate < 0.9) { int stats_left = av1_firstpass_info_future_count(firstpass_info, next_stats_index); if (stats_left >= still_interval) { int j; // Look ahead a few frames to see if static condition persists... for (j = 0; j < still_interval; ++j) { const FIRSTPASS_STATS *stats = av1_firstpass_info_peek(firstpass_info, next_stats_index + j); if (stats->pcnt_inter - stats->pcnt_motion < 0.999) break; } // Only if it does do we signal a transition to still. return j == still_interval; } } return 0; } // This function detects a flash through the high relative pcnt_second_ref // score in the frame following a flash frame. The offset passed in should // reflect this. static int detect_flash(const TWO_PASS *twopass, const TWO_PASS_FRAME *twopass_frame, const int offset) { const FIRSTPASS_STATS *const next_frame = read_frame_stats(twopass, twopass_frame, offset); // What we are looking for here is a situation where there is a // brief break in prediction (such as a flash) but subsequent frames // are reasonably well predicted by an earlier (pre flash) frame. // The recovery after a flash is indicated by a high pcnt_second_ref // compared to pcnt_inter. return next_frame != NULL && next_frame->pcnt_second_ref > next_frame->pcnt_inter && next_frame->pcnt_second_ref >= 0.5; } // Update the motion related elements to the GF arf boost calculation. static void accumulate_frame_motion_stats(const FIRSTPASS_STATS *stats, GF_GROUP_STATS *gf_stats, double f_w, double f_h) { const double pct = stats->pcnt_motion; // Accumulate Motion In/Out of frame stats. gf_stats->this_frame_mv_in_out = stats->mv_in_out_count * pct; gf_stats->mv_in_out_accumulator += gf_stats->this_frame_mv_in_out; gf_stats->abs_mv_in_out_accumulator += fabs(gf_stats->this_frame_mv_in_out); // Accumulate a measure of how uniform (or conversely how random) the motion // field is (a ratio of abs(mv) / mv). if (pct > 0.05) { const double mvr_ratio = fabs(stats->mvr_abs) / DOUBLE_DIVIDE_CHECK(fabs(stats->MVr)); const double mvc_ratio = fabs(stats->mvc_abs) / DOUBLE_DIVIDE_CHECK(fabs(stats->MVc)); gf_stats->mv_ratio_accumulator += pct * (mvr_ratio < stats->mvr_abs * f_h ? mvr_ratio : stats->mvr_abs * f_h); gf_stats->mv_ratio_accumulator += pct * (mvc_ratio < stats->mvc_abs * f_w ? mvc_ratio : stats->mvc_abs * f_w); } } static void accumulate_this_frame_stats(const FIRSTPASS_STATS *stats, const double mod_frame_err, GF_GROUP_STATS *gf_stats) { gf_stats->gf_group_err += mod_frame_err; #if GROUP_ADAPTIVE_MAXQ gf_stats->gf_group_raw_error += stats->coded_error; #endif gf_stats->gf_group_skip_pct += stats->intra_skip_pct; gf_stats->gf_group_inactive_zone_rows += stats->inactive_zone_rows; } static void accumulate_next_frame_stats(const FIRSTPASS_STATS *stats, const int flash_detected, const int frames_since_key, const int cur_idx, GF_GROUP_STATS *gf_stats, int f_w, int f_h) { accumulate_frame_motion_stats(stats, gf_stats, f_w, f_h); // sum up the metric values of current gf group gf_stats->avg_sr_coded_error += stats->sr_coded_error; gf_stats->avg_pcnt_second_ref += stats->pcnt_second_ref; gf_stats->avg_new_mv_count += stats->new_mv_count; gf_stats->avg_wavelet_energy += stats->frame_avg_wavelet_energy; if (fabs(stats->raw_error_stdev) > 0.000001) { gf_stats->non_zero_stdev_count++; gf_stats->avg_raw_err_stdev += stats->raw_error_stdev; } // Accumulate the effect of prediction quality decay if (!flash_detected) { gf_stats->last_loop_decay_rate = gf_stats->loop_decay_rate; gf_stats->loop_decay_rate = get_prediction_decay_rate(stats); gf_stats->decay_accumulator = gf_stats->decay_accumulator * gf_stats->loop_decay_rate; // Monitor for static sections. if ((frames_since_key + cur_idx - 1) > 1) { gf_stats->zero_motion_accumulator = AOMMIN( gf_stats->zero_motion_accumulator, get_zero_motion_factor(stats)); } } } static void average_gf_stats(const int total_frame, GF_GROUP_STATS *gf_stats) { if (total_frame) { gf_stats->avg_sr_coded_error /= total_frame; gf_stats->avg_pcnt_second_ref /= total_frame; gf_stats->avg_new_mv_count /= total_frame; gf_stats->avg_wavelet_energy /= total_frame; } if (gf_stats->non_zero_stdev_count) gf_stats->avg_raw_err_stdev /= gf_stats->non_zero_stdev_count; } #define BOOST_FACTOR 12.5 static double baseline_err_per_mb(const FRAME_INFO *frame_info) { unsigned int screen_area = frame_info->frame_height * frame_info->frame_width; // Use a different error per mb factor for calculating boost for // different formats. if (screen_area <= 640 * 360) { return 500.0; } else { return 1000.0; } } static double calc_frame_boost(const PRIMARY_RATE_CONTROL *p_rc, const FRAME_INFO *frame_info, const FIRSTPASS_STATS *this_frame, double this_frame_mv_in_out, double max_boost) { double frame_boost; const double lq = av1_convert_qindex_to_q(p_rc->avg_frame_qindex[INTER_FRAME], frame_info->bit_depth); const double boost_q_correction = AOMMIN((0.5 + (lq * 0.015)), 1.5); const double active_area = calculate_active_area(frame_info, this_frame); // Underlying boost factor is based on inter error ratio. frame_boost = AOMMAX(baseline_err_per_mb(frame_info) * active_area, this_frame->intra_error * active_area) / DOUBLE_DIVIDE_CHECK(this_frame->coded_error); frame_boost = frame_boost * BOOST_FACTOR * boost_q_correction; // Increase boost for frames where new data coming into frame (e.g. zoom out). // Slightly reduce boost if there is a net balance of motion out of the frame // (zoom in). The range for this_frame_mv_in_out is -1.0 to +1.0. if (this_frame_mv_in_out > 0.0) frame_boost += frame_boost * (this_frame_mv_in_out * 2.0); // In the extreme case the boost is halved. else frame_boost += frame_boost * (this_frame_mv_in_out / 2.0); return AOMMIN(frame_boost, max_boost * boost_q_correction); } static double calc_kf_frame_boost(const PRIMARY_RATE_CONTROL *p_rc, const FRAME_INFO *frame_info, const FIRSTPASS_STATS *this_frame, double *sr_accumulator, double max_boost) { double frame_boost; const double lq = av1_convert_qindex_to_q(p_rc->avg_frame_qindex[INTER_FRAME], frame_info->bit_depth); const double boost_q_correction = AOMMIN((0.50 + (lq * 0.015)), 2.00); const double active_area = calculate_active_area(frame_info, this_frame); // Underlying boost factor is based on inter error ratio. frame_boost = AOMMAX(baseline_err_per_mb(frame_info) * active_area, this_frame->intra_error * active_area) / DOUBLE_DIVIDE_CHECK( (this_frame->coded_error + *sr_accumulator) * active_area); // Update the accumulator for second ref error difference. // This is intended to give an indication of how much the coded error is // increasing over time. *sr_accumulator += (this_frame->sr_coded_error - this_frame->coded_error); *sr_accumulator = AOMMAX(0.0, *sr_accumulator); // Q correction and scaling // The 40.0 value here is an experimentally derived baseline minimum. // This value is in line with the minimum per frame boost in the alt_ref // boost calculation. frame_boost = ((frame_boost + 40.0) * boost_q_correction); return AOMMIN(frame_boost, max_boost * boost_q_correction); } static int get_projected_gfu_boost(const PRIMARY_RATE_CONTROL *p_rc, int gfu_boost, int frames_to_project, int num_stats_used_for_gfu_boost) { /* * If frames_to_project is equal to num_stats_used_for_gfu_boost, * it means that gfu_boost was calculated over frames_to_project to * begin with(ie; all stats required were available), hence return * the original boost. */ if (num_stats_used_for_gfu_boost >= frames_to_project) return gfu_boost; double min_boost_factor = sqrt(p_rc->baseline_gf_interval); // Get the current tpl factor (number of frames = frames_to_project). double tpl_factor = av1_get_gfu_boost_projection_factor( min_boost_factor, MAX_GFUBOOST_FACTOR, frames_to_project); // Get the tpl factor when number of frames = num_stats_used_for_prior_boost. double tpl_factor_num_stats = av1_get_gfu_boost_projection_factor( min_boost_factor, MAX_GFUBOOST_FACTOR, num_stats_used_for_gfu_boost); int projected_gfu_boost = (int)rint((tpl_factor * gfu_boost) / tpl_factor_num_stats); return projected_gfu_boost; } #define GF_MAX_BOOST 90.0 #define GF_MIN_BOOST 50 #define MIN_DECAY_FACTOR 0.01 int av1_calc_arf_boost(const TWO_PASS *twopass, const TWO_PASS_FRAME *twopass_frame, const PRIMARY_RATE_CONTROL *p_rc, FRAME_INFO *frame_info, int offset, int f_frames, int b_frames, int *num_fpstats_used, int *num_fpstats_required, int project_gfu_boost) { int i; GF_GROUP_STATS gf_stats; init_gf_stats(&gf_stats); double boost_score = (double)NORMAL_BOOST; int arf_boost; int flash_detected = 0; if (num_fpstats_used) *num_fpstats_used = 0; // Search forward from the proposed arf/next gf position. for (i = 0; i < f_frames; ++i) { const FIRSTPASS_STATS *this_frame = read_frame_stats(twopass, twopass_frame, i + offset); if (this_frame == NULL) break; // Update the motion related elements to the boost calculation. accumulate_frame_motion_stats(this_frame, &gf_stats, frame_info->frame_width, frame_info->frame_height); // We want to discount the flash frame itself and the recovery // frame that follows as both will have poor scores. flash_detected = detect_flash(twopass, twopass_frame, i + offset) || detect_flash(twopass, twopass_frame, i + offset + 1); // Accumulate the effect of prediction quality decay. if (!flash_detected) { gf_stats.decay_accumulator *= get_prediction_decay_rate(this_frame); gf_stats.decay_accumulator = gf_stats.decay_accumulator < MIN_DECAY_FACTOR ? MIN_DECAY_FACTOR : gf_stats.decay_accumulator; } boost_score += gf_stats.decay_accumulator * calc_frame_boost(p_rc, frame_info, this_frame, gf_stats.this_frame_mv_in_out, GF_MAX_BOOST); if (num_fpstats_used) (*num_fpstats_used)++; } arf_boost = (int)boost_score; // Reset for backward looking loop. boost_score = 0.0; init_gf_stats(&gf_stats); // Search backward towards last gf position. for (i = -1; i >= -b_frames; --i) { const FIRSTPASS_STATS *this_frame = read_frame_stats(twopass, twopass_frame, i + offset); if (this_frame == NULL) break; // Update the motion related elements to the boost calculation. accumulate_frame_motion_stats(this_frame, &gf_stats, frame_info->frame_width, frame_info->frame_height); // We want to discount the the flash frame itself and the recovery // frame that follows as both will have poor scores. flash_detected = detect_flash(twopass, twopass_frame, i + offset) || detect_flash(twopass, twopass_frame, i + offset + 1); // Cumulative effect of prediction quality decay. if (!flash_detected) { gf_stats.decay_accumulator *= get_prediction_decay_rate(this_frame); gf_stats.decay_accumulator = gf_stats.decay_accumulator < MIN_DECAY_FACTOR ? MIN_DECAY_FACTOR : gf_stats.decay_accumulator; } boost_score += gf_stats.decay_accumulator * calc_frame_boost(p_rc, frame_info, this_frame, gf_stats.this_frame_mv_in_out, GF_MAX_BOOST); if (num_fpstats_used) (*num_fpstats_used)++; } arf_boost += (int)boost_score; if (project_gfu_boost) { assert(num_fpstats_required != NULL); assert(num_fpstats_used != NULL); *num_fpstats_required = f_frames + b_frames; arf_boost = get_projected_gfu_boost(p_rc, arf_boost, *num_fpstats_required, *num_fpstats_used); } if (arf_boost < ((b_frames + f_frames) * GF_MIN_BOOST)) arf_boost = ((b_frames + f_frames) * GF_MIN_BOOST); return arf_boost; } // Calculate a section intra ratio used in setting max loop filter. static int calculate_section_intra_ratio(const FIRSTPASS_STATS *begin, const FIRSTPASS_STATS *end, int section_length) { const FIRSTPASS_STATS *s = begin; double intra_error = 0.0; double coded_error = 0.0; int i = 0; while (s < end && i < section_length) { intra_error += s->intra_error; coded_error += s->coded_error; ++s; ++i; } return (int)(intra_error / DOUBLE_DIVIDE_CHECK(coded_error)); } /*!\brief Calculates the bit target for this GF/ARF group * * \ingroup rate_control * * Calculates the total bits to allocate in this GF/ARF group. * * \param[in] cpi Top-level encoder structure * \param[in] gf_group_err Cumulative coded error score for the * frames making up this group. * * \return The target total number of bits for this GF/ARF group. */ static int64_t calculate_total_gf_group_bits(AV1_COMP *cpi, double gf_group_err) { const RATE_CONTROL *const rc = &cpi->rc; const PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; const TWO_PASS *const twopass = &cpi->ppi->twopass; const int max_bits = frame_max_bits(rc, &cpi->oxcf); int64_t total_group_bits; // Calculate the bits to be allocated to the group as a whole. if ((twopass->kf_group_bits > 0) && (twopass->kf_group_error_left > 0)) { total_group_bits = (int64_t)(twopass->kf_group_bits * (gf_group_err / twopass->kf_group_error_left)); } else { total_group_bits = 0; } // Clamp odd edge cases. total_group_bits = (total_group_bits < 0) ? 0 : (total_group_bits > twopass->kf_group_bits) ? twopass->kf_group_bits : total_group_bits; // Clip based on user supplied data rate variability limit. if (total_group_bits > (int64_t)max_bits * p_rc->baseline_gf_interval) total_group_bits = (int64_t)max_bits * p_rc->baseline_gf_interval; return total_group_bits; } // Calculate the number of bits to assign to boosted frames in a group. static int calculate_boost_bits(int frame_count, int boost, int64_t total_group_bits) { int allocation_chunks; // return 0 for invalid inputs (could arise e.g. through rounding errors) if (!boost || (total_group_bits <= 0)) return 0; if (frame_count <= 0) return (int)(AOMMIN(total_group_bits, INT_MAX)); allocation_chunks = (frame_count * 100) + boost; // Prevent overflow. if (boost > 1023) { int divisor = boost >> 10; boost /= divisor; allocation_chunks /= divisor; } // Calculate the number of extra bits for use in the boosted frame or frames. return AOMMAX((int)(((int64_t)boost * total_group_bits) / allocation_chunks), 0); } // Calculate the boost factor based on the number of bits assigned, i.e. the // inverse of calculate_boost_bits(). static int calculate_boost_factor(int frame_count, int bits, int64_t total_group_bits) { return (int)(100.0 * frame_count * bits / (total_group_bits - bits)); } // Reduce the number of bits assigned to keyframe or arf if necessary, to // prevent bitrate spikes that may break level constraints. // frame_type: 0: keyframe; 1: arf. static int adjust_boost_bits_for_target_level(const AV1_COMP *const cpi, RATE_CONTROL *const rc, int bits_assigned, int64_t group_bits, int frame_type) { const AV1_COMMON *const cm = &cpi->common; const SequenceHeader *const seq_params = cm->seq_params; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; const int temporal_layer_id = cm->temporal_layer_id; const int spatial_layer_id = cm->spatial_layer_id; for (int index = 0; index < seq_params->operating_points_cnt_minus_1 + 1; ++index) { if (!is_in_operating_point(seq_params->operating_point_idc[index], temporal_layer_id, spatial_layer_id)) { continue; } const AV1_LEVEL target_level = cpi->ppi->level_params.target_seq_level_idx[index]; if (target_level >= SEQ_LEVELS) continue; assert(is_valid_seq_level_idx(target_level)); const double level_bitrate_limit = av1_get_max_bitrate_for_level( target_level, seq_params->tier[0], seq_params->profile); const int target_bits_per_frame = (int)(level_bitrate_limit / cpi->framerate); if (frame_type == 0) { // Maximum bits for keyframe is 8 times the target_bits_per_frame. const int level_enforced_max_kf_bits = target_bits_per_frame * 8; if (bits_assigned > level_enforced_max_kf_bits) { const int frames = rc->frames_to_key - 1; p_rc->kf_boost = calculate_boost_factor( frames, level_enforced_max_kf_bits, group_bits); bits_assigned = calculate_boost_bits(frames, p_rc->kf_boost, group_bits); } } else if (frame_type == 1) { // Maximum bits for arf is 4 times the target_bits_per_frame. const int level_enforced_max_arf_bits = target_bits_per_frame * 4; if (bits_assigned > level_enforced_max_arf_bits) { p_rc->gfu_boost = calculate_boost_factor(p_rc->baseline_gf_interval, level_enforced_max_arf_bits, group_bits); bits_assigned = calculate_boost_bits(p_rc->baseline_gf_interval, p_rc->gfu_boost, group_bits); } } else { assert(0); } } return bits_assigned; } // Allocate bits to each frame in a GF / ARF group double layer_fraction[MAX_ARF_LAYERS + 1] = { 1.0, 0.70, 0.55, 0.60, 0.60, 1.0, 1.0 }; static void allocate_gf_group_bits(GF_GROUP *gf_group, PRIMARY_RATE_CONTROL *const p_rc, RATE_CONTROL *const rc, int64_t gf_group_bits, int gf_arf_bits, int key_frame, int use_arf) { int64_t total_group_bits = gf_group_bits; int base_frame_bits; const int gf_group_size = gf_group->size; int layer_frames[MAX_ARF_LAYERS + 1] = { 0 }; // For key frames the frame target rate is already set and it // is also the golden frame. // === [frame_index == 0] === int frame_index = !!key_frame; // Subtract the extra bits set aside for ARF frames from the Group Total if (use_arf) total_group_bits -= gf_arf_bits; int num_frames = AOMMAX(1, p_rc->baseline_gf_interval - (rc->frames_since_key == 0)); base_frame_bits = (int)(total_group_bits / num_frames); // Check the number of frames in each layer in case we have a // non standard group length. int max_arf_layer = gf_group->max_layer_depth - 1; for (int idx = frame_index; idx < gf_group_size; ++idx) { if ((gf_group->update_type[idx] == ARF_UPDATE) || (gf_group->update_type[idx] == INTNL_ARF_UPDATE)) { layer_frames[gf_group->layer_depth[idx]]++; } } // Allocate extra bits to each ARF layer int i; int layer_extra_bits[MAX_ARF_LAYERS + 1] = { 0 }; assert(max_arf_layer <= MAX_ARF_LAYERS); for (i = 1; i <= max_arf_layer; ++i) { double fraction = (i == max_arf_layer) ? 1.0 : layer_fraction[i]; layer_extra_bits[i] = (int)((gf_arf_bits * fraction) / AOMMAX(1, layer_frames[i])); gf_arf_bits -= (int)(gf_arf_bits * fraction); } // Now combine ARF layer and baseline bits to give total bits for each frame. int arf_extra_bits; for (int idx = frame_index; idx < gf_group_size; ++idx) { switch (gf_group->update_type[idx]) { case ARF_UPDATE: case INTNL_ARF_UPDATE: arf_extra_bits = layer_extra_bits[gf_group->layer_depth[idx]]; gf_group->bit_allocation[idx] = base_frame_bits + arf_extra_bits; break; case INTNL_OVERLAY_UPDATE: case OVERLAY_UPDATE: gf_group->bit_allocation[idx] = 0; break; default: gf_group->bit_allocation[idx] = base_frame_bits; break; } } // Set the frame following the current GOP to 0 bit allocation. For ARF // groups, this next frame will be overlay frame, which is the first frame // in the next GOP. For GF group, next GOP will overwrite the rate allocation. // Setting this frame to use 0 bit (of out the current GOP budget) will // simplify logics in reference frame management. if (gf_group_size < MAX_STATIC_GF_GROUP_LENGTH) gf_group->bit_allocation[gf_group_size] = 0; } // Returns true if KF group and GF group both are almost completely static. static INLINE int is_almost_static(double gf_zero_motion, int kf_zero_motion, int is_lap_enabled) { if (is_lap_enabled) { /* * when LAP enabled kf_zero_motion is not reliable, so use strict * constraint on gf_zero_motion. */ return (gf_zero_motion >= 0.999); } else { return (gf_zero_motion >= 0.995) && (kf_zero_motion >= STATIC_KF_GROUP_THRESH); } } #define ARF_ABS_ZOOM_THRESH 4.4 static INLINE int detect_gf_cut(AV1_COMP *cpi, int frame_index, int cur_start, int flash_detected, int active_max_gf_interval, int active_min_gf_interval, GF_GROUP_STATS *gf_stats) { RATE_CONTROL *const rc = &cpi->rc; TWO_PASS *const twopass = &cpi->ppi->twopass; AV1_COMMON *const cm = &cpi->common; // Motion breakout threshold for loop below depends on image size. const double mv_ratio_accumulator_thresh = (cm->height + cm->width) / 4.0; if (!flash_detected) { // Break clause to detect very still sections after motion. For example, // a static image after a fade or other transition. // TODO(angiebird): This is a temporary change, we will avoid using // twopass_frame.stats_in in the follow-up CL int index = (int)(cpi->twopass_frame.stats_in - twopass->stats_buf_ctx->stats_in_start); if (detect_transition_to_still(&twopass->firstpass_info, index, rc->min_gf_interval, frame_index - cur_start, 5, gf_stats->loop_decay_rate, gf_stats->last_loop_decay_rate)) { return 1; } } // Some conditions to breakout after min interval. if (frame_index - cur_start >= active_min_gf_interval && // If possible don't break very close to a kf (rc->frames_to_key - frame_index >= rc->min_gf_interval) && ((frame_index - cur_start) & 0x01) && !flash_detected && (gf_stats->mv_ratio_accumulator > mv_ratio_accumulator_thresh || gf_stats->abs_mv_in_out_accumulator > ARF_ABS_ZOOM_THRESH)) { return 1; } // If almost totally static, we will not use the the max GF length later, // so we can continue for more frames. if (((frame_index - cur_start) >= active_max_gf_interval + 1) && !is_almost_static(gf_stats->zero_motion_accumulator, twopass->kf_zeromotion_pct, cpi->ppi->lap_enabled)) { return 1; } return 0; } static int is_shorter_gf_interval_better( AV1_COMP *cpi, const EncodeFrameParams *frame_params) { const RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; int gop_length_decision_method = cpi->sf.tpl_sf.gop_length_decision_method; int shorten_gf_interval; av1_tpl_preload_rc_estimate(cpi, frame_params); if (gop_length_decision_method == 2) { // GF group length is decided based on GF boost and tpl stats of ARFs from // base layer, (base+1) layer. shorten_gf_interval = (p_rc->gfu_boost < p_rc->num_stats_used_for_gfu_boost * GF_MIN_BOOST * 1.4) && !av1_tpl_setup_stats(cpi, 3, frame_params); } else { int do_complete_tpl = 1; GF_GROUP *const gf_group = &cpi->ppi->gf_group; int is_temporal_filter_enabled = (rc->frames_since_key > 0 && gf_group->arf_index > -1); if (gop_length_decision_method == 1) { // Check if tpl stats of ARFs from base layer, (base+1) layer, // (base+2) layer can decide the GF group length. int gop_length_eval = av1_tpl_setup_stats(cpi, 2, frame_params); if (gop_length_eval != 2) { do_complete_tpl = 0; shorten_gf_interval = !gop_length_eval; } } if (do_complete_tpl) { // Decide GF group length based on complete tpl stats. shorten_gf_interval = !av1_tpl_setup_stats(cpi, 1, frame_params); // Tpl stats is reused when the ARF is temporally filtered and GF // interval is not shortened. if (is_temporal_filter_enabled && !shorten_gf_interval) { cpi->skip_tpl_setup_stats = 1; #if CONFIG_BITRATE_ACCURACY && !CONFIG_THREE_PASS assert(cpi->gf_frame_index == 0); av1_vbr_rc_update_q_index_list(&cpi->vbr_rc_info, &cpi->ppi->tpl_data, gf_group, cpi->common.seq_params->bit_depth); #endif // CONFIG_BITRATE_ACCURACY } } } return shorten_gf_interval; } #define MIN_SHRINK_LEN 6 // the minimum length of gf if we are shrinking #define SMOOTH_FILT_LEN 7 #define HALF_FILT_LEN (SMOOTH_FILT_LEN / 2) #define WINDOW_SIZE 7 #define HALF_WIN (WINDOW_SIZE / 2) // A 7-tap gaussian smooth filter const double smooth_filt[SMOOTH_FILT_LEN] = { 0.006, 0.061, 0.242, 0.383, 0.242, 0.061, 0.006 }; // Smooth filter intra_error and coded_error in firstpass stats. // If stats[i].is_flash==1, the ith element should not be used in the filtering. static void smooth_filter_stats(const FIRSTPASS_STATS *stats, int start_idx, int last_idx, double *filt_intra_err, double *filt_coded_err) { int i, j; for (i = start_idx; i <= last_idx; i++) { double total_wt = 0; for (j = -HALF_FILT_LEN; j <= HALF_FILT_LEN; j++) { int idx = AOMMIN(AOMMAX(i + j, start_idx), last_idx); if (stats[idx].is_flash) continue; filt_intra_err[i] += smooth_filt[j + HALF_FILT_LEN] * stats[idx].intra_error; total_wt += smooth_filt[j + HALF_FILT_LEN]; } if (total_wt > 0.01) { filt_intra_err[i] /= total_wt; } else { filt_intra_err[i] = stats[i].intra_error; } } for (i = start_idx; i <= last_idx; i++) { double total_wt = 0; for (j = -HALF_FILT_LEN; j <= HALF_FILT_LEN; j++) { int idx = AOMMIN(AOMMAX(i + j, start_idx), last_idx); // Coded error involves idx and idx - 1. if (stats[idx].is_flash || (idx > 0 && stats[idx - 1].is_flash)) continue; filt_coded_err[i] += smooth_filt[j + HALF_FILT_LEN] * stats[idx].coded_error; total_wt += smooth_filt[j + HALF_FILT_LEN]; } if (total_wt > 0.01) { filt_coded_err[i] /= total_wt; } else { filt_coded_err[i] = stats[i].coded_error; } } } // Calculate gradient static void get_gradient(const double *values, int start, int last, double *grad) { if (start == last) { grad[start] = 0; return; } for (int i = start; i <= last; i++) { int prev = AOMMAX(i - 1, start); int next = AOMMIN(i + 1, last); grad[i] = (values[next] - values[prev]) / (next - prev); } } static int find_next_scenecut(const FIRSTPASS_STATS *const stats_start, int first, int last) { // Identify unstable areas caused by scenecuts. // Find the max and 2nd max coded error, and the average of the rest frames. // If there is only one frame that yields a huge coded error, it is likely a // scenecut. double this_ratio, max_prev_ratio, max_next_ratio, max_prev_coded, max_next_coded; if (last - first == 0) return -1; for (int i = first; i <= last; i++) { if (stats_start[i].is_flash || (i > 0 && stats_start[i - 1].is_flash)) continue; double temp_intra = AOMMAX(stats_start[i].intra_error, 0.01); this_ratio = stats_start[i].coded_error / temp_intra; // find the avg ratio in the preceding neighborhood max_prev_ratio = 0; max_prev_coded = 0; for (int j = AOMMAX(first, i - HALF_WIN); j < i; j++) { if (stats_start[j].is_flash || (j > 0 && stats_start[j - 1].is_flash)) continue; temp_intra = AOMMAX(stats_start[j].intra_error, 0.01); double temp_ratio = stats_start[j].coded_error / temp_intra; if (temp_ratio > max_prev_ratio) { max_prev_ratio = temp_ratio; } if (stats_start[j].coded_error > max_prev_coded) { max_prev_coded = stats_start[j].coded_error; } } // find the avg ratio in the following neighborhood max_next_ratio = 0; max_next_coded = 0; for (int j = i + 1; j <= AOMMIN(i + HALF_WIN, last); j++) { if (stats_start[i].is_flash || (i > 0 && stats_start[i - 1].is_flash)) continue; temp_intra = AOMMAX(stats_start[j].intra_error, 0.01); double temp_ratio = stats_start[j].coded_error / temp_intra; if (temp_ratio > max_next_ratio) { max_next_ratio = temp_ratio; } if (stats_start[j].coded_error > max_next_coded) { max_next_coded = stats_start[j].coded_error; } } if (max_prev_ratio < 0.001 && max_next_ratio < 0.001) { // the ratios are very small, only check a small fixed threshold if (this_ratio < 0.02) continue; } else { // check if this frame has a larger ratio than the neighborhood double max_sr = stats_start[i].sr_coded_error; if (i < last) max_sr = AOMMAX(max_sr, stats_start[i + 1].sr_coded_error); double max_sr_fr_ratio = max_sr / AOMMAX(stats_start[i].coded_error, 0.01); if (max_sr_fr_ratio > 1.2) continue; if (this_ratio < 2 * AOMMAX(max_prev_ratio, max_next_ratio) && stats_start[i].coded_error < 2 * AOMMAX(max_prev_coded, max_next_coded)) { continue; } } return i; } return -1; } // Remove the region with index next_region. // parameter merge: 0: merge with previous; 1: merge with next; 2: // merge with both, take type from previous if possible // After removing, next_region will be the index of the next region. static void remove_region(int merge, REGIONS *regions, int *num_regions, int *next_region) { int k = *next_region; assert(k < *num_regions); if (*num_regions == 1) { *num_regions = 0; return; } if (k == 0) { merge = 1; } else if (k == *num_regions - 1) { merge = 0; } int num_merge = (merge == 2) ? 2 : 1; switch (merge) { case 0: regions[k - 1].last = regions[k].last; *next_region = k; break; case 1: regions[k + 1].start = regions[k].start; *next_region = k + 1; break; case 2: regions[k - 1].last = regions[k + 1].last; *next_region = k; break; default: assert(0); } *num_regions -= num_merge; for (k = *next_region - (merge == 1); k < *num_regions; k++) { regions[k] = regions[k + num_merge]; } } // Insert a region in the cur_region_idx. The start and last should both be in // the current region. After insertion, the cur_region_idx will point to the // last region that was splitted from the original region. static void insert_region(int start, int last, REGION_TYPES type, REGIONS *regions, int *num_regions, int *cur_region_idx) { int k = *cur_region_idx; REGION_TYPES this_region_type = regions[k].type; int this_region_last = regions[k].last; int num_add = (start != regions[k].start) + (last != regions[k].last); // move the following regions further to the back for (int r = *num_regions - 1; r > k; r--) { regions[r + num_add] = regions[r]; } *num_regions += num_add; if (start > regions[k].start) { regions[k].last = start - 1; k++; regions[k].start = start; } regions[k].type = type; if (last < this_region_last) { regions[k].last = last; k++; regions[k].start = last + 1; regions[k].last = this_region_last; regions[k].type = this_region_type; } else { regions[k].last = this_region_last; } *cur_region_idx = k; } // Get the average of stats inside a region. static void analyze_region(const FIRSTPASS_STATS *stats, int k, REGIONS *regions) { int i; regions[k].avg_cor_coeff = 0; regions[k].avg_sr_fr_ratio = 0; regions[k].avg_intra_err = 0; regions[k].avg_coded_err = 0; int check_first_sr = (k != 0); for (i = regions[k].start; i <= regions[k].last; i++) { if (i > regions[k].start || check_first_sr) { double num_frames = (double)(regions[k].last - regions[k].start + check_first_sr); double max_coded_error = AOMMAX(stats[i].coded_error, stats[i - 1].coded_error); double this_ratio = stats[i].sr_coded_error / AOMMAX(max_coded_error, 0.001); regions[k].avg_sr_fr_ratio += this_ratio / num_frames; } regions[k].avg_intra_err += stats[i].intra_error / (double)(regions[k].last - regions[k].start + 1); regions[k].avg_coded_err += stats[i].coded_error / (double)(regions[k].last - regions[k].start + 1); regions[k].avg_cor_coeff += AOMMAX(stats[i].cor_coeff, 0.001) / (double)(regions[k].last - regions[k].start + 1); regions[k].avg_noise_var += AOMMAX(stats[i].noise_var, 0.001) / (double)(regions[k].last - regions[k].start + 1); } } // Calculate the regions stats of every region. static void get_region_stats(const FIRSTPASS_STATS *stats, REGIONS *regions, int num_regions) { for (int k = 0; k < num_regions; k++) { analyze_region(stats, k, regions); } } // Find tentative stable regions static int find_stable_regions(const FIRSTPASS_STATS *stats, const double *grad_coded, int this_start, int this_last, REGIONS *regions) { int i, j, k = 0; regions[k].start = this_start; for (i = this_start; i <= this_last; i++) { // Check mean and variance of stats in a window double mean_intra = 0.001, var_intra = 0.001; double mean_coded = 0.001, var_coded = 0.001; int count = 0; for (j = -HALF_WIN; j <= HALF_WIN; j++) { int idx = AOMMIN(AOMMAX(i + j, this_start), this_last); if (stats[idx].is_flash || (idx > 0 && stats[idx - 1].is_flash)) continue; mean_intra += stats[idx].intra_error; var_intra += stats[idx].intra_error * stats[idx].intra_error; mean_coded += stats[idx].coded_error; var_coded += stats[idx].coded_error * stats[idx].coded_error; count++; } REGION_TYPES cur_type; if (count > 0) { mean_intra /= (double)count; var_intra /= (double)count; mean_coded /= (double)count; var_coded /= (double)count; int is_intra_stable = (var_intra / (mean_intra * mean_intra) < 1.03); int is_coded_stable = (var_coded / (mean_coded * mean_coded) < 1.04 && fabs(grad_coded[i]) / mean_coded < 0.05) || mean_coded / mean_intra < 0.05; int is_coded_small = mean_coded < 0.5 * mean_intra; cur_type = (is_intra_stable && is_coded_stable && is_coded_small) ? STABLE_REGION : HIGH_VAR_REGION; } else { cur_type = HIGH_VAR_REGION; } // mark a new region if type changes if (i == regions[k].start) { // first frame in the region regions[k].type = cur_type; } else if (cur_type != regions[k].type) { // Append a new region regions[k].last = i - 1; regions[k + 1].start = i; regions[k + 1].type = cur_type; k++; } } regions[k].last = this_last; return k + 1; } // Clean up regions that should be removed or merged. static void cleanup_regions(REGIONS *regions, int *num_regions) { int k = 0; while (k < *num_regions) { if ((k > 0 && regions[k - 1].type == regions[k].type && regions[k].type != SCENECUT_REGION) || regions[k].last < regions[k].start) { remove_region(0, regions, num_regions, &k); } else { k++; } } } // Remove regions that are of type and shorter than length. // Merge it with its neighboring regions. static void remove_short_regions(REGIONS *regions, int *num_regions, REGION_TYPES type, int length) { int k = 0; while (k < *num_regions && (*num_regions) > 1) { if ((regions[k].last - regions[k].start + 1 < length && regions[k].type == type)) { // merge current region with the previous and next regions remove_region(2, regions, num_regions, &k); } else { k++; } } cleanup_regions(regions, num_regions); } static void adjust_unstable_region_bounds(const FIRSTPASS_STATS *stats, REGIONS *regions, int *num_regions) { int i, j, k; // Remove regions that are too short. Likely noise. remove_short_regions(regions, num_regions, STABLE_REGION, HALF_WIN); remove_short_regions(regions, num_regions, HIGH_VAR_REGION, HALF_WIN); get_region_stats(stats, regions, *num_regions); // Adjust region boundaries. The thresholds are empirically obtained, but // overall the performance is not very sensitive to small changes to them. for (k = 0; k < *num_regions; k++) { if (regions[k].type == STABLE_REGION) continue; if (k > 0) { // Adjust previous boundary. // First find the average intra/coded error in the previous // neighborhood. double avg_intra_err = 0; const int starti = AOMMAX(regions[k - 1].last - WINDOW_SIZE + 1, regions[k - 1].start + 1); const int lasti = regions[k - 1].last; int counti = 0; for (i = starti; i <= lasti; i++) { avg_intra_err += stats[i].intra_error; counti++; } if (counti > 0) { avg_intra_err = AOMMAX(avg_intra_err / (double)counti, 0.001); int count_coded = 0, count_grad = 0; for (j = lasti + 1; j <= regions[k].last; j++) { const int intra_close = fabs(stats[j].intra_error - avg_intra_err) / avg_intra_err < 0.1; const int coded_small = stats[j].coded_error / avg_intra_err < 0.1; const int coeff_close = stats[j].cor_coeff > 0.995; if (!coeff_close || !coded_small) count_coded--; if (intra_close && count_coded >= 0 && count_grad >= 0) { // this frame probably belongs to the previous stable region regions[k - 1].last = j; regions[k].start = j + 1; } else { break; } } } } // if k > 0 if (k < *num_regions - 1) { // Adjust next boundary. // First find the average intra/coded error in the next neighborhood. double avg_intra_err = 0; const int starti = regions[k + 1].start; const int lasti = AOMMIN(regions[k + 1].last - 1, regions[k + 1].start + WINDOW_SIZE - 1); int counti = 0; for (i = starti; i <= lasti; i++) { avg_intra_err += stats[i].intra_error; counti++; } if (counti > 0) { avg_intra_err = AOMMAX(avg_intra_err / (double)counti, 0.001); // At the boundary, coded error is large, but still the frame is stable int count_coded = 1, count_grad = 1; for (j = starti - 1; j >= regions[k].start; j--) { const int intra_close = fabs(stats[j].intra_error - avg_intra_err) / avg_intra_err < 0.1; const int coded_small = stats[j + 1].coded_error / avg_intra_err < 0.1; const int coeff_close = stats[j].cor_coeff > 0.995; if (!coeff_close || !coded_small) count_coded--; if (intra_close && count_coded >= 0 && count_grad >= 0) { // this frame probably belongs to the next stable region regions[k + 1].start = j; regions[k].last = j - 1; } else { break; } } } } // if k < *num_regions - 1 } // end of loop over all regions cleanup_regions(regions, num_regions); remove_short_regions(regions, num_regions, HIGH_VAR_REGION, HALF_WIN); get_region_stats(stats, regions, *num_regions); // If a stable regions has higher error than neighboring high var regions, // or if the stable region has a lower average correlation, // then it should be merged with them k = 0; while (k < *num_regions && (*num_regions) > 1) { if (regions[k].type == STABLE_REGION && (regions[k].last - regions[k].start + 1) < 2 * WINDOW_SIZE && ((k > 0 && // previous regions (regions[k].avg_coded_err > regions[k - 1].avg_coded_err * 1.01 || regions[k].avg_cor_coeff < regions[k - 1].avg_cor_coeff * 0.999)) && (k < *num_regions - 1 && // next region (regions[k].avg_coded_err > regions[k + 1].avg_coded_err * 1.01 || regions[k].avg_cor_coeff < regions[k + 1].avg_cor_coeff * 0.999)))) { // merge current region with the previous and next regions remove_region(2, regions, num_regions, &k); analyze_region(stats, k - 1, regions); } else if (regions[k].type == HIGH_VAR_REGION && (regions[k].last - regions[k].start + 1) < 2 * WINDOW_SIZE && ((k > 0 && // previous regions (regions[k].avg_coded_err < regions[k - 1].avg_coded_err * 0.99 || regions[k].avg_cor_coeff > regions[k - 1].avg_cor_coeff * 1.001)) && (k < *num_regions - 1 && // next region (regions[k].avg_coded_err < regions[k + 1].avg_coded_err * 0.99 || regions[k].avg_cor_coeff > regions[k + 1].avg_cor_coeff * 1.001)))) { // merge current region with the previous and next regions remove_region(2, regions, num_regions, &k); analyze_region(stats, k - 1, regions); } else { k++; } } remove_short_regions(regions, num_regions, STABLE_REGION, WINDOW_SIZE); remove_short_regions(regions, num_regions, HIGH_VAR_REGION, HALF_WIN); } // Identify blending regions. static void find_blending_regions(const FIRSTPASS_STATS *stats, REGIONS *regions, int *num_regions) { int i, k = 0; // Blending regions will have large content change, therefore will have a // large consistent change in intra error. int count_stable = 0; while (k < *num_regions) { if (regions[k].type == STABLE_REGION) { k++; count_stable++; continue; } int dir = 0; int start = 0, last; for (i = regions[k].start; i <= regions[k].last; i++) { // First mark the regions that has consistent large change of intra error. if (k == 0 && i == regions[k].start) continue; if (stats[i].is_flash || (i > 0 && stats[i - 1].is_flash)) continue; double grad = stats[i].intra_error - stats[i - 1].intra_error; int large_change = fabs(grad) / AOMMAX(stats[i].intra_error, 0.01) > 0.05; int this_dir = 0; if (large_change) { this_dir = (grad > 0) ? 1 : -1; } // the current trend continues if (dir == this_dir) continue; if (dir != 0) { // Mark the end of a new large change group and add it last = i - 1; insert_region(start, last, BLENDING_REGION, regions, num_regions, &k); } dir = this_dir; if (k == 0 && i == regions[k].start + 1) { start = i - 1; } else { start = i; } } if (dir != 0) { last = regions[k].last; insert_region(start, last, BLENDING_REGION, regions, num_regions, &k); } k++; } // If the blending region has very low correlation, mark it as high variance // since we probably cannot benefit from it anyways. get_region_stats(stats, regions, *num_regions); for (k = 0; k < *num_regions; k++) { if (regions[k].type != BLENDING_REGION) continue; if (regions[k].last == regions[k].start || regions[k].avg_cor_coeff < 0.6 || count_stable == 0) regions[k].type = HIGH_VAR_REGION; } get_region_stats(stats, regions, *num_regions); // It is possible for blending to result in a "dip" in intra error (first // decrease then increase). Therefore we need to find the dip and combine the // two regions. k = 1; while (k < *num_regions) { if (k < *num_regions - 1 && regions[k].type == HIGH_VAR_REGION) { // Check if this short high variance regions is actually in the middle of // a blending region. if (regions[k - 1].type == BLENDING_REGION && regions[k + 1].type == BLENDING_REGION && regions[k].last - regions[k].start < 3) { int prev_dir = (stats[regions[k - 1].last].intra_error - stats[regions[k - 1].last - 1].intra_error) > 0 ? 1 : -1; int next_dir = (stats[regions[k + 1].last].intra_error - stats[regions[k + 1].last - 1].intra_error) > 0 ? 1 : -1; if (prev_dir < 0 && next_dir > 0) { // This is possibly a mid region of blending. Check the ratios double ratio_thres = AOMMIN(regions[k - 1].avg_sr_fr_ratio, regions[k + 1].avg_sr_fr_ratio) * 0.95; if (regions[k].avg_sr_fr_ratio > ratio_thres) { regions[k].type = BLENDING_REGION; remove_region(2, regions, num_regions, &k); analyze_region(stats, k - 1, regions); continue; } } } } // Check if we have a pair of consecutive blending regions. if (regions[k - 1].type == BLENDING_REGION && regions[k].type == BLENDING_REGION) { int prev_dir = (stats[regions[k - 1].last].intra_error - stats[regions[k - 1].last - 1].intra_error) > 0 ? 1 : -1; int next_dir = (stats[regions[k].last].intra_error - stats[regions[k].last - 1].intra_error) > 0 ? 1 : -1; // if both are too short, no need to check int total_length = regions[k].last - regions[k - 1].start + 1; if (total_length < 4) { regions[k - 1].type = HIGH_VAR_REGION; k++; continue; } int to_merge = 0; if (prev_dir < 0 && next_dir > 0) { // In this case we check the last frame in the previous region. double prev_length = (double)(regions[k - 1].last - regions[k - 1].start + 1); double last_ratio, ratio_thres; if (prev_length < 2.01) { // if the previous region is very short double max_coded_error = AOMMAX(stats[regions[k - 1].last].coded_error, stats[regions[k - 1].last - 1].coded_error); last_ratio = stats[regions[k - 1].last].sr_coded_error / AOMMAX(max_coded_error, 0.001); ratio_thres = regions[k].avg_sr_fr_ratio * 0.95; } else { double max_coded_error = AOMMAX(stats[regions[k - 1].last].coded_error, stats[regions[k - 1].last - 1].coded_error); last_ratio = stats[regions[k - 1].last].sr_coded_error / AOMMAX(max_coded_error, 0.001); double prev_ratio = (regions[k - 1].avg_sr_fr_ratio * prev_length - last_ratio) / (prev_length - 1.0); ratio_thres = AOMMIN(prev_ratio, regions[k].avg_sr_fr_ratio) * 0.95; } if (last_ratio > ratio_thres) { to_merge = 1; } } if (to_merge) { remove_region(0, regions, num_regions, &k); analyze_region(stats, k - 1, regions); continue; } else { // These are possibly two separate blending regions. Mark the boundary // frame as HIGH_VAR_REGION to separate the two. int prev_k = k - 1; insert_region(regions[prev_k].last, regions[prev_k].last, HIGH_VAR_REGION, regions, num_regions, &prev_k); analyze_region(stats, prev_k, regions); k = prev_k + 1; analyze_region(stats, k, regions); } } k++; } cleanup_regions(regions, num_regions); } // Clean up decision for blendings. Remove blending regions that are too short. // Also if a very short high var region is between a blending and a stable // region, just merge it with one of them. static void cleanup_blendings(REGIONS *regions, int *num_regions) { int k = 0; while (k<*num_regions && * num_regions> 1) { int is_short_blending = regions[k].type == BLENDING_REGION && regions[k].last - regions[k].start + 1 < 5; int is_short_hv = regions[k].type == HIGH_VAR_REGION && regions[k].last - regions[k].start + 1 < 5; int has_stable_neighbor = ((k > 0 && regions[k - 1].type == STABLE_REGION) || (k < *num_regions - 1 && regions[k + 1].type == STABLE_REGION)); int has_blend_neighbor = ((k > 0 && regions[k - 1].type == BLENDING_REGION) || (k < *num_regions - 1 && regions[k + 1].type == BLENDING_REGION)); int total_neighbors = (k > 0) + (k < *num_regions - 1); if (is_short_blending || (is_short_hv && has_stable_neighbor + has_blend_neighbor >= total_neighbors)) { // Remove this region.Try to determine whether to combine it with the // previous or next region. int merge; double prev_diff = (k > 0) ? fabs(regions[k].avg_cor_coeff - regions[k - 1].avg_cor_coeff) : 1; double next_diff = (k < *num_regions - 1) ? fabs(regions[k].avg_cor_coeff - regions[k + 1].avg_cor_coeff) : 1; // merge == 0 means to merge with previous, 1 means to merge with next merge = prev_diff > next_diff; remove_region(merge, regions, num_regions, &k); } else { k++; } } cleanup_regions(regions, num_regions); } static void free_firstpass_stats_buffers(REGIONS *temp_regions, double *filt_intra_err, double *filt_coded_err, double *grad_coded) { aom_free(temp_regions); aom_free(filt_intra_err); aom_free(filt_coded_err); aom_free(grad_coded); } // Identify stable and unstable regions from first pass stats. // stats_start points to the first frame to analyze. // |offset| is the offset from the current frame to the frame stats_start is // pointing to. // Returns 0 on success, -1 on memory allocation failure. static int identify_regions(const FIRSTPASS_STATS *const stats_start, int total_frames, int offset, REGIONS *regions, int *total_regions) { int k; if (total_frames <= 1) return 0; // store the initial decisions REGIONS *temp_regions = (REGIONS *)aom_malloc(total_frames * sizeof(temp_regions[0])); // buffers for filtered stats double *filt_intra_err = (double *)aom_calloc(total_frames, sizeof(*filt_intra_err)); double *filt_coded_err = (double *)aom_calloc(total_frames, sizeof(*filt_coded_err)); double *grad_coded = (double *)aom_calloc(total_frames, sizeof(*grad_coded)); if (!(temp_regions && filt_intra_err && filt_coded_err && grad_coded)) { free_firstpass_stats_buffers(temp_regions, filt_intra_err, filt_coded_err, grad_coded); return -1; } av1_zero_array(temp_regions, total_frames); int cur_region = 0, this_start = 0, this_last; int next_scenecut = -1; do { // first get the obvious scenecuts next_scenecut = find_next_scenecut(stats_start, this_start, total_frames - 1); this_last = (next_scenecut >= 0) ? (next_scenecut - 1) : total_frames - 1; // low-pass filter the needed stats smooth_filter_stats(stats_start, this_start, this_last, filt_intra_err, filt_coded_err); get_gradient(filt_coded_err, this_start, this_last, grad_coded); // find tentative stable regions and unstable regions int num_regions = find_stable_regions(stats_start, grad_coded, this_start, this_last, temp_regions); adjust_unstable_region_bounds(stats_start, temp_regions, &num_regions); get_region_stats(stats_start, temp_regions, num_regions); // Try to identify blending regions in the unstable regions find_blending_regions(stats_start, temp_regions, &num_regions); cleanup_blendings(temp_regions, &num_regions); // The flash points should all be considered high variance points k = 0; while (k < num_regions) { if (temp_regions[k].type != STABLE_REGION) { k++; continue; } int start = temp_regions[k].start; int last = temp_regions[k].last; for (int i = start; i <= last; i++) { if (stats_start[i].is_flash) { insert_region(i, i, HIGH_VAR_REGION, temp_regions, &num_regions, &k); } } k++; } cleanup_regions(temp_regions, &num_regions); // copy the regions in the scenecut group for (k = 0; k < num_regions; k++) { if (temp_regions[k].last < temp_regions[k].start && k == num_regions - 1) { num_regions--; break; } regions[k + cur_region] = temp_regions[k]; } cur_region += num_regions; // add the scenecut region if (next_scenecut > -1) { // add the scenecut region, and find the next scenecut regions[cur_region].type = SCENECUT_REGION; regions[cur_region].start = next_scenecut; regions[cur_region].last = next_scenecut; cur_region++; this_start = next_scenecut + 1; } } while (next_scenecut >= 0); *total_regions = cur_region; get_region_stats(stats_start, regions, *total_regions); for (k = 0; k < *total_regions; k++) { // If scenecuts are very minor, mark them as high variance. if (regions[k].type != SCENECUT_REGION || regions[k].avg_cor_coeff * (1 - stats_start[regions[k].start].noise_var / regions[k].avg_intra_err) < 0.8) { continue; } regions[k].type = HIGH_VAR_REGION; } cleanup_regions(regions, total_regions); get_region_stats(stats_start, regions, *total_regions); for (k = 0; k < *total_regions; k++) { regions[k].start += offset; regions[k].last += offset; } free_firstpass_stats_buffers(temp_regions, filt_intra_err, filt_coded_err, grad_coded); return 0; } static int find_regions_index(const REGIONS *regions, int num_regions, int frame_idx) { for (int k = 0; k < num_regions; k++) { if (regions[k].start <= frame_idx && regions[k].last >= frame_idx) { return k; } } return -1; } /*!\brief Determine the length of future GF groups. * * \ingroup gf_group_algo * This function decides the gf group length of future frames in batch * * \param[in] cpi Top-level encoder structure * \param[in] max_gop_length Maximum length of the GF group * \param[in] max_intervals Maximum number of intervals to decide * * \remark Nothing is returned. Instead, cpi->ppi->rc.gf_intervals is * changed to store the decided GF group lengths. */ static void calculate_gf_length(AV1_COMP *cpi, int max_gop_length, int max_intervals) { RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; TWO_PASS *const twopass = &cpi->ppi->twopass; FIRSTPASS_STATS next_frame; const FIRSTPASS_STATS *const start_pos = cpi->twopass_frame.stats_in; const FIRSTPASS_STATS *const stats = start_pos - (rc->frames_since_key == 0); const int f_w = cpi->common.width; const int f_h = cpi->common.height; int i; int flash_detected; av1_zero(next_frame); if (has_no_stats_stage(cpi)) { for (i = 0; i < MAX_NUM_GF_INTERVALS; i++) { p_rc->gf_intervals[i] = AOMMIN(rc->max_gf_interval, max_gop_length); } p_rc->cur_gf_index = 0; rc->intervals_till_gf_calculate_due = MAX_NUM_GF_INTERVALS; return; } // TODO(urvang): Try logic to vary min and max interval based on q. const int active_min_gf_interval = rc->min_gf_interval; const int active_max_gf_interval = AOMMIN(rc->max_gf_interval, max_gop_length); const int min_shrink_int = AOMMAX(MIN_SHRINK_LEN, active_min_gf_interval); i = (rc->frames_since_key == 0); max_intervals = cpi->ppi->lap_enabled ? 1 : max_intervals; int count_cuts = 1; // If cpi->gf_state.arf_gf_boost_lst is 0, we are starting with a KF or GF. int cur_start = -1 + !cpi->ppi->gf_state.arf_gf_boost_lst, cur_last; int cut_pos[MAX_NUM_GF_INTERVALS + 1] = { -1 }; int cut_here; GF_GROUP_STATS gf_stats; init_gf_stats(&gf_stats); while (count_cuts < max_intervals + 1) { // reaches next key frame, break here if (i >= rc->frames_to_key) { cut_here = 2; } else if (i - cur_start >= rc->static_scene_max_gf_interval) { // reached maximum len, but nothing special yet (almost static) // let's look at the next interval cut_here = 1; } else if (EOF == input_stats(twopass, &cpi->twopass_frame, &next_frame)) { // reaches last frame, break cut_here = 2; } else { // Test for the case where there is a brief flash but the prediction // quality back to an earlier frame is then restored. flash_detected = detect_flash(twopass, &cpi->twopass_frame, 0); // TODO(bohanli): remove redundant accumulations here, or unify // this and the ones in define_gf_group accumulate_next_frame_stats(&next_frame, flash_detected, rc->frames_since_key, i, &gf_stats, f_w, f_h); cut_here = detect_gf_cut(cpi, i, cur_start, flash_detected, active_max_gf_interval, active_min_gf_interval, &gf_stats); } if (cut_here) { cur_last = i - 1; // the current last frame in the gf group int ori_last = cur_last; // The region frame idx does not start from the same frame as cur_start // and cur_last. Need to offset them. int offset = rc->frames_since_key - p_rc->regions_offset; REGIONS *regions = p_rc->regions; int num_regions = p_rc->num_regions; int scenecut_idx = -1; // only try shrinking if interval smaller than active_max_gf_interval if (cur_last - cur_start <= active_max_gf_interval && cur_last > cur_start) { // find the region indices of where the first and last frame belong. int k_start = find_regions_index(regions, num_regions, cur_start + offset); int k_last = find_regions_index(regions, num_regions, cur_last + offset); if (cur_start + offset == 0) k_start = 0; // See if we have a scenecut in between for (int r = k_start + 1; r <= k_last; r++) { if (regions[r].type == SCENECUT_REGION && regions[r].last - offset - cur_start > active_min_gf_interval) { scenecut_idx = r; break; } } // if the found scenecut is very close to the end, ignore it. if (regions[num_regions - 1].last - regions[scenecut_idx].last < 4) { scenecut_idx = -1; } if (scenecut_idx != -1) { // If we have a scenecut, then stop at it. // TODO(bohanli): add logic here to stop before the scenecut and for // the next gop start from the scenecut with GF int is_minor_sc = (regions[scenecut_idx].avg_cor_coeff * (1 - stats[regions[scenecut_idx].start - offset].noise_var / regions[scenecut_idx].avg_intra_err) > 0.6); cur_last = regions[scenecut_idx].last - offset - !is_minor_sc; } else { int is_last_analysed = (k_last == num_regions - 1) && (cur_last + offset == regions[k_last].last); int not_enough_regions = k_last - k_start <= 1 + (regions[k_start].type == SCENECUT_REGION); // if we are very close to the end, then do not shrink since it may // introduce intervals that are too short if (!(is_last_analysed && not_enough_regions)) { const double arf_length_factor = 0.1; double best_score = 0; int best_j = -1; const int first_frame = regions[0].start - offset; const int last_frame = regions[num_regions - 1].last - offset; // score of how much the arf helps the whole GOP double base_score = 0.0; // Accumulate base_score in for (int j = cur_start + 1; j < cur_start + min_shrink_int; j++) { if (stats + j >= twopass->stats_buf_ctx->stats_in_end) break; base_score = (base_score + 1.0) * stats[j].cor_coeff; } int met_blending = 0; // Whether we have met blending areas before int last_blending = 0; // Whether the previous frame if blending for (int j = cur_start + min_shrink_int; j <= cur_last; j++) { if (stats + j >= twopass->stats_buf_ctx->stats_in_end) break; base_score = (base_score + 1.0) * stats[j].cor_coeff; int this_reg = find_regions_index(regions, num_regions, j + offset); if (this_reg < 0) continue; // A GOP should include at most 1 blending region. if (regions[this_reg].type == BLENDING_REGION) { last_blending = 1; if (met_blending) { break; } else { base_score = 0; continue; } } else { if (last_blending) met_blending = 1; last_blending = 0; } // Add the factor of how good the neighborhood is for this // candidate arf. double this_score = arf_length_factor * base_score; double temp_accu_coeff = 1.0; // following frames int count_f = 0; for (int n = j + 1; n <= j + 3 && n <= last_frame; n++) { if (stats + n >= twopass->stats_buf_ctx->stats_in_end) break; temp_accu_coeff *= stats[n].cor_coeff; this_score += temp_accu_coeff * sqrt(AOMMAX(0.5, 1 - stats[n].noise_var / AOMMAX(stats[n].intra_error, 0.001))); count_f++; } // preceding frames temp_accu_coeff = 1.0; for (int n = j; n > j - 3 * 2 + count_f && n > first_frame; n--) { if (stats + n < twopass->stats_buf_ctx->stats_in_start) break; temp_accu_coeff *= stats[n].cor_coeff; this_score += temp_accu_coeff * sqrt(AOMMAX(0.5, 1 - stats[n].noise_var / AOMMAX(stats[n].intra_error, 0.001))); } if (this_score > best_score) { best_score = this_score; best_j = j; } } // For blending areas, move one more frame in case we missed the // first blending frame. int best_reg = find_regions_index(regions, num_regions, best_j + offset); if (best_reg < num_regions - 1 && best_reg > 0) { if (regions[best_reg - 1].type == BLENDING_REGION && regions[best_reg + 1].type == BLENDING_REGION) { if (best_j + offset == regions[best_reg].start && best_j + offset < regions[best_reg].last) { best_j += 1; } else if (best_j + offset == regions[best_reg].last && best_j + offset > regions[best_reg].start) { best_j -= 1; } } } if (cur_last - best_j < 2) best_j = cur_last; if (best_j > 0 && best_score > 0.1) cur_last = best_j; // if cannot find anything, just cut at the original place. } } } cut_pos[count_cuts] = cur_last; count_cuts++; // reset pointers to the shrunken location cpi->twopass_frame.stats_in = start_pos + cur_last; cur_start = cur_last; int cur_region_idx = find_regions_index(regions, num_regions, cur_start + 1 + offset); if (cur_region_idx >= 0) if (regions[cur_region_idx].type == SCENECUT_REGION) cur_start++; i = cur_last; if (cut_here > 1 && cur_last == ori_last) break; // reset accumulators init_gf_stats(&gf_stats); } ++i; } // save intervals rc->intervals_till_gf_calculate_due = count_cuts - 1; for (int n = 1; n < count_cuts; n++) { p_rc->gf_intervals[n - 1] = cut_pos[n] - cut_pos[n - 1]; } p_rc->cur_gf_index = 0; cpi->twopass_frame.stats_in = start_pos; } static void correct_frames_to_key(AV1_COMP *cpi) { int lookahead_size = (int)av1_lookahead_depth(cpi->ppi->lookahead, cpi->compressor_stage); if (lookahead_size < av1_lookahead_pop_sz(cpi->ppi->lookahead, cpi->compressor_stage)) { assert( IMPLIES(cpi->oxcf.pass != AOM_RC_ONE_PASS && cpi->ppi->frames_left > 0, lookahead_size == cpi->ppi->frames_left)); cpi->rc.frames_to_key = AOMMIN(cpi->rc.frames_to_key, lookahead_size); } else if (cpi->ppi->frames_left > 0) { // Correct frames to key based on limit cpi->rc.frames_to_key = AOMMIN(cpi->rc.frames_to_key, cpi->ppi->frames_left); } } /*!\brief Define a GF group in one pass mode when no look ahead stats are * available. * * \ingroup gf_group_algo * This function defines the structure of a GF group, along with various * parameters regarding bit-allocation and quality setup in the special * case of one pass encoding where no lookahead stats are avialable. * * \param[in] cpi Top-level encoder structure * * \remark Nothing is returned. Instead, cpi->ppi->gf_group is changed. */ static void define_gf_group_pass0(AV1_COMP *cpi) { RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; GF_GROUP *const gf_group = &cpi->ppi->gf_group; const AV1EncoderConfig *const oxcf = &cpi->oxcf; const GFConfig *const gf_cfg = &oxcf->gf_cfg; int target; if (oxcf->q_cfg.aq_mode == CYCLIC_REFRESH_AQ) { av1_cyclic_refresh_set_golden_update(cpi); } else { p_rc->baseline_gf_interval = p_rc->gf_intervals[p_rc->cur_gf_index]; rc->intervals_till_gf_calculate_due--; p_rc->cur_gf_index++; } // correct frames_to_key when lookahead queue is flushing correct_frames_to_key(cpi); if (p_rc->baseline_gf_interval > rc->frames_to_key) p_rc->baseline_gf_interval = rc->frames_to_key; p_rc->gfu_boost = DEFAULT_GF_BOOST; p_rc->constrained_gf_group = (p_rc->baseline_gf_interval >= rc->frames_to_key) ? 1 : 0; gf_group->max_layer_depth_allowed = oxcf->gf_cfg.gf_max_pyr_height; // Rare case when the look-ahead is less than the target GOP length, can't // generate ARF frame. if (p_rc->baseline_gf_interval > gf_cfg->lag_in_frames || !is_altref_enabled(gf_cfg->lag_in_frames, gf_cfg->enable_auto_arf) || p_rc->baseline_gf_interval < rc->min_gf_interval) gf_group->max_layer_depth_allowed = 0; // Set up the structure of this Group-Of-Pictures (same as GF_GROUP) av1_gop_setup_structure(cpi); // Allocate bits to each of the frames in the GF group. // TODO(sarahparker) Extend this to work with pyramid structure. for (int cur_index = 0; cur_index < gf_group->size; ++cur_index) { const FRAME_UPDATE_TYPE cur_update_type = gf_group->update_type[cur_index]; if (oxcf->rc_cfg.mode == AOM_CBR) { if (cur_update_type == KF_UPDATE) { target = av1_calc_iframe_target_size_one_pass_cbr(cpi); } else { target = av1_calc_pframe_target_size_one_pass_cbr(cpi, cur_update_type); } } else { if (cur_update_type == KF_UPDATE) { target = av1_calc_iframe_target_size_one_pass_vbr(cpi); } else { target = av1_calc_pframe_target_size_one_pass_vbr(cpi, cur_update_type); } } gf_group->bit_allocation[cur_index] = target; } } static INLINE void set_baseline_gf_interval(PRIMARY_RATE_CONTROL *p_rc, int arf_position) { p_rc->baseline_gf_interval = arf_position; } // initialize GF_GROUP_STATS static void init_gf_stats(GF_GROUP_STATS *gf_stats) { gf_stats->gf_group_err = 0.0; gf_stats->gf_group_raw_error = 0.0; gf_stats->gf_group_skip_pct = 0.0; gf_stats->gf_group_inactive_zone_rows = 0.0; gf_stats->mv_ratio_accumulator = 0.0; gf_stats->decay_accumulator = 1.0; gf_stats->zero_motion_accumulator = 1.0; gf_stats->loop_decay_rate = 1.0; gf_stats->last_loop_decay_rate = 1.0; gf_stats->this_frame_mv_in_out = 0.0; gf_stats->mv_in_out_accumulator = 0.0; gf_stats->abs_mv_in_out_accumulator = 0.0; gf_stats->avg_sr_coded_error = 0.0; gf_stats->avg_pcnt_second_ref = 0.0; gf_stats->avg_new_mv_count = 0.0; gf_stats->avg_wavelet_energy = 0.0; gf_stats->avg_raw_err_stdev = 0.0; gf_stats->non_zero_stdev_count = 0; } static void accumulate_gop_stats(AV1_COMP *cpi, int is_intra_only, int f_w, int f_h, FIRSTPASS_STATS *next_frame, const FIRSTPASS_STATS *start_pos, GF_GROUP_STATS *gf_stats, int *idx) { int i, flash_detected; TWO_PASS *const twopass = &cpi->ppi->twopass; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; RATE_CONTROL *const rc = &cpi->rc; FRAME_INFO *frame_info = &cpi->frame_info; const AV1EncoderConfig *const oxcf = &cpi->oxcf; init_gf_stats(gf_stats); av1_zero(*next_frame); // If this is a key frame or the overlay from a previous arf then // the error score / cost of this frame has already been accounted for. i = is_intra_only; // get the determined gf group length from p_rc->gf_intervals while (i < p_rc->gf_intervals[p_rc->cur_gf_index]) { // read in the next frame if (EOF == input_stats(twopass, &cpi->twopass_frame, next_frame)) break; // Accumulate error score of frames in this gf group. double mod_frame_err = calculate_modified_err(frame_info, twopass, oxcf, next_frame); // accumulate stats for this frame accumulate_this_frame_stats(next_frame, mod_frame_err, gf_stats); ++i; } reset_fpf_position(&cpi->twopass_frame, start_pos); i = is_intra_only; input_stats(twopass, &cpi->twopass_frame, next_frame); while (i < p_rc->gf_intervals[p_rc->cur_gf_index]) { // read in the next frame if (EOF == input_stats(twopass, &cpi->twopass_frame, next_frame)) break; // Test for the case where there is a brief flash but the prediction // quality back to an earlier frame is then restored. flash_detected = detect_flash(twopass, &cpi->twopass_frame, 0); // accumulate stats for next frame accumulate_next_frame_stats(next_frame, flash_detected, rc->frames_since_key, i, gf_stats, f_w, f_h); ++i; } i = p_rc->gf_intervals[p_rc->cur_gf_index]; average_gf_stats(i, gf_stats); *idx = i; } static void update_gop_length(RATE_CONTROL *rc, PRIMARY_RATE_CONTROL *p_rc, int idx, int is_final_pass) { if (is_final_pass) { rc->intervals_till_gf_calculate_due--; p_rc->cur_gf_index++; } // Was the group length constrained by the requirement for a new KF? p_rc->constrained_gf_group = (idx >= rc->frames_to_key) ? 1 : 0; set_baseline_gf_interval(p_rc, idx); rc->frames_till_gf_update_due = p_rc->baseline_gf_interval; } #define MAX_GF_BOOST 5400 #define REDUCE_GF_LENGTH_THRESH 4 #define REDUCE_GF_LENGTH_TO_KEY_THRESH 9 #define REDUCE_GF_LENGTH_BY 1 static void set_gop_bits_boost(AV1_COMP *cpi, int i, int is_intra_only, int is_final_pass, int use_alt_ref, int alt_offset, const FIRSTPASS_STATS *start_pos, GF_GROUP_STATS *gf_stats) { // Should we use the alternate reference frame. AV1_COMMON *const cm = &cpi->common; RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; TWO_PASS *const twopass = &cpi->ppi->twopass; GF_GROUP *gf_group = &cpi->ppi->gf_group; FRAME_INFO *frame_info = &cpi->frame_info; const AV1EncoderConfig *const oxcf = &cpi->oxcf; const RateControlCfg *const rc_cfg = &oxcf->rc_cfg; int ext_len = i - is_intra_only; if (use_alt_ref) { const int forward_frames = (rc->frames_to_key - i >= ext_len) ? ext_len : AOMMAX(0, rc->frames_to_key - i); // Calculate the boost for alt ref. p_rc->gfu_boost = av1_calc_arf_boost( twopass, &cpi->twopass_frame, p_rc, frame_info, alt_offset, forward_frames, ext_len, &p_rc->num_stats_used_for_gfu_boost, &p_rc->num_stats_required_for_gfu_boost, cpi->ppi->lap_enabled); } else { reset_fpf_position(&cpi->twopass_frame, start_pos); p_rc->gfu_boost = AOMMIN( MAX_GF_BOOST, av1_calc_arf_boost( twopass, &cpi->twopass_frame, p_rc, frame_info, alt_offset, ext_len, 0, &p_rc->num_stats_used_for_gfu_boost, &p_rc->num_stats_required_for_gfu_boost, cpi->ppi->lap_enabled)); } #define LAST_ALR_BOOST_FACTOR 0.2f p_rc->arf_boost_factor = 1.0; if (use_alt_ref && !is_lossless_requested(rc_cfg)) { // Reduce the boost of altref in the last gf group if (rc->frames_to_key - ext_len == REDUCE_GF_LENGTH_BY || rc->frames_to_key - ext_len == 0) { p_rc->arf_boost_factor = LAST_ALR_BOOST_FACTOR; } } // Reset the file position. reset_fpf_position(&cpi->twopass_frame, start_pos); if (cpi->ppi->lap_enabled) { // Since we don't have enough stats to know the actual error of the // gf group, we assume error of each frame to be equal to 1 and set // the error of the group as baseline_gf_interval. gf_stats->gf_group_err = p_rc->baseline_gf_interval; } // Calculate the bits to be allocated to the gf/arf group as a whole p_rc->gf_group_bits = calculate_total_gf_group_bits(cpi, gf_stats->gf_group_err); #if GROUP_ADAPTIVE_MAXQ // Calculate an estimate of the maxq needed for the group. // We are more aggressive about correcting for sections // where there could be significant overshoot than for easier // sections where we do not wish to risk creating an overshoot // of the allocated bit budget. if ((rc_cfg->mode != AOM_Q) && (p_rc->baseline_gf_interval > 1) && is_final_pass) { const int vbr_group_bits_per_frame = (int)(p_rc->gf_group_bits / p_rc->baseline_gf_interval); const double group_av_err = gf_stats->gf_group_raw_error / p_rc->baseline_gf_interval; const double group_av_skip_pct = gf_stats->gf_group_skip_pct / p_rc->baseline_gf_interval; const double group_av_inactive_zone = ((gf_stats->gf_group_inactive_zone_rows * 2) / (p_rc->baseline_gf_interval * (double)cm->mi_params.mb_rows)); int tmp_q; tmp_q = get_twopass_worst_quality( cpi, group_av_err, (group_av_skip_pct + group_av_inactive_zone), vbr_group_bits_per_frame); rc->active_worst_quality = AOMMAX(tmp_q, rc->active_worst_quality >> 1); } #endif // Adjust KF group bits and error remaining. if (is_final_pass) twopass->kf_group_error_left -= gf_stats->gf_group_err; // Reset the file position. reset_fpf_position(&cpi->twopass_frame, start_pos); // Calculate a section intra ratio used in setting max loop filter. if (rc->frames_since_key != 0) { twopass->section_intra_rating = calculate_section_intra_ratio( start_pos, twopass->stats_buf_ctx->stats_in_end, p_rc->baseline_gf_interval); } av1_gop_bit_allocation(cpi, rc, gf_group, rc->frames_since_key == 0, use_alt_ref, p_rc->gf_group_bits); // TODO(jingning): Generalize this condition. if (is_final_pass) { cpi->ppi->gf_state.arf_gf_boost_lst = use_alt_ref; // Reset rolling actual and target bits counters for ARF groups. twopass->rolling_arf_group_target_bits = 1; twopass->rolling_arf_group_actual_bits = 1; } #if CONFIG_BITRATE_ACCURACY if (is_final_pass) { av1_vbr_rc_set_gop_bit_budget(&cpi->vbr_rc_info, p_rc->baseline_gf_interval); } #endif } /*!\brief Define a GF group. * * \ingroup gf_group_algo * This function defines the structure of a GF group, along with various * parameters regarding bit-allocation and quality setup. * * \param[in] cpi Top-level encoder structure * \param[in] frame_params Structure with frame parameters * \param[in] is_final_pass Whether this is the final pass for the * GF group, or a trial (non-zero) * * \remark Nothing is returned. Instead, cpi->ppi->gf_group is changed. */ static void define_gf_group(AV1_COMP *cpi, EncodeFrameParams *frame_params, int is_final_pass) { AV1_COMMON *const cm = &cpi->common; RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; const AV1EncoderConfig *const oxcf = &cpi->oxcf; TWO_PASS *const twopass = &cpi->ppi->twopass; FIRSTPASS_STATS next_frame; const FIRSTPASS_STATS *const start_pos = cpi->twopass_frame.stats_in; GF_GROUP *gf_group = &cpi->ppi->gf_group; const GFConfig *const gf_cfg = &oxcf->gf_cfg; const RateControlCfg *const rc_cfg = &oxcf->rc_cfg; const int f_w = cm->width; const int f_h = cm->height; int i; const int is_intra_only = rc->frames_since_key == 0; cpi->ppi->internal_altref_allowed = (gf_cfg->gf_max_pyr_height > 1); // Reset the GF group data structures unless this is a key // frame in which case it will already have been done. if (!is_intra_only) { av1_zero(cpi->ppi->gf_group); cpi->gf_frame_index = 0; } if (has_no_stats_stage(cpi)) { define_gf_group_pass0(cpi); return; } if (cpi->third_pass_ctx && oxcf->pass == AOM_RC_THIRD_PASS) { int ret = define_gf_group_pass3(cpi, frame_params, is_final_pass); if (ret == 0) return; av1_free_thirdpass_ctx(cpi->third_pass_ctx); cpi->third_pass_ctx = NULL; } // correct frames_to_key when lookahead queue is emptying if (cpi->ppi->lap_enabled) { correct_frames_to_key(cpi); } GF_GROUP_STATS gf_stats; accumulate_gop_stats(cpi, is_intra_only, f_w, f_h, &next_frame, start_pos, &gf_stats, &i); const int can_disable_arf = !gf_cfg->gf_min_pyr_height; // If this is a key frame or the overlay from a previous arf then // the error score / cost of this frame has already been accounted for. const int active_min_gf_interval = rc->min_gf_interval; // Disable internal ARFs for "still" gf groups. // zero_motion_accumulator: minimum percentage of (0,0) motion; // avg_sr_coded_error: average of the SSE per pixel of each frame; // avg_raw_err_stdev: average of the standard deviation of (0,0) // motion error per block of each frame. const int can_disable_internal_arfs = gf_cfg->gf_min_pyr_height <= 1; if (can_disable_internal_arfs && gf_stats.zero_motion_accumulator > MIN_ZERO_MOTION && gf_stats.avg_sr_coded_error < MAX_SR_CODED_ERROR && gf_stats.avg_raw_err_stdev < MAX_RAW_ERR_VAR) { cpi->ppi->internal_altref_allowed = 0; } int use_alt_ref; if (can_disable_arf) { use_alt_ref = !is_almost_static(gf_stats.zero_motion_accumulator, twopass->kf_zeromotion_pct, cpi->ppi->lap_enabled) && p_rc->use_arf_in_this_kf_group && (i < gf_cfg->lag_in_frames) && (i >= MIN_GF_INTERVAL); } else { use_alt_ref = p_rc->use_arf_in_this_kf_group && (i < gf_cfg->lag_in_frames) && (i > 2); } if (use_alt_ref) { gf_group->max_layer_depth_allowed = gf_cfg->gf_max_pyr_height; } else { gf_group->max_layer_depth_allowed = 0; } int alt_offset = 0; // The length reduction strategy is tweaked for certain cases, and doesn't // work well for certain other cases. const int allow_gf_length_reduction = ((rc_cfg->mode == AOM_Q && rc_cfg->cq_level <= 128) || !cpi->ppi->internal_altref_allowed) && !is_lossless_requested(rc_cfg); if (allow_gf_length_reduction && use_alt_ref) { // adjust length of this gf group if one of the following condition met // 1: only one overlay frame left and this gf is too long // 2: next gf group is too short to have arf compared to the current gf // maximum length of next gf group const int next_gf_len = rc->frames_to_key - i; const int single_overlay_left = next_gf_len == 0 && i > REDUCE_GF_LENGTH_THRESH; // the next gf is probably going to have a ARF but it will be shorter than // this gf const int unbalanced_gf = i > REDUCE_GF_LENGTH_TO_KEY_THRESH && next_gf_len + 1 < REDUCE_GF_LENGTH_TO_KEY_THRESH && next_gf_len + 1 >= rc->min_gf_interval; if (single_overlay_left || unbalanced_gf) { const int roll_back = REDUCE_GF_LENGTH_BY; // Reduce length only if active_min_gf_interval will be respected later. if (i - roll_back >= active_min_gf_interval + 1) { alt_offset = -roll_back; i -= roll_back; if (is_final_pass) rc->intervals_till_gf_calculate_due = 0; p_rc->gf_intervals[p_rc->cur_gf_index] -= roll_back; reset_fpf_position(&cpi->twopass_frame, start_pos); accumulate_gop_stats(cpi, is_intra_only, f_w, f_h, &next_frame, start_pos, &gf_stats, &i); } } } update_gop_length(rc, p_rc, i, is_final_pass); // Set up the structure of this Group-Of-Pictures (same as GF_GROUP) av1_gop_setup_structure(cpi); set_gop_bits_boost(cpi, i, is_intra_only, is_final_pass, use_alt_ref, alt_offset, start_pos, &gf_stats); frame_params->frame_type = rc->frames_since_key == 0 ? KEY_FRAME : INTER_FRAME; frame_params->show_frame = !(gf_group->update_type[cpi->gf_frame_index] == ARF_UPDATE || gf_group->update_type[cpi->gf_frame_index] == INTNL_ARF_UPDATE); } /*!\brief Define a GF group for the third apss. * * \ingroup gf_group_algo * This function defines the structure of a GF group for the third pass, along * with various parameters regarding bit-allocation and quality setup based on * the two-pass bitstream. * Much of the function still uses the strategies used for the second pass and * relies on first pass statistics. It is expected that over time these portions * would be replaced with strategies specific to the third pass. * * \param[in] cpi Top-level encoder structure * \param[in] frame_params Structure with frame parameters * \param[in] is_final_pass Whether this is the final pass for the * GF group, or a trial (non-zero) * * \return 0: Success; * -1: There are conflicts between the bitstream and current config * The values in cpi->ppi->gf_group are also changed. */ static int define_gf_group_pass3(AV1_COMP *cpi, EncodeFrameParams *frame_params, int is_final_pass) { if (!cpi->third_pass_ctx) return -1; AV1_COMMON *const cm = &cpi->common; RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; const AV1EncoderConfig *const oxcf = &cpi->oxcf; FIRSTPASS_STATS next_frame; const FIRSTPASS_STATS *const start_pos = cpi->twopass_frame.stats_in; GF_GROUP *gf_group = &cpi->ppi->gf_group; const GFConfig *const gf_cfg = &oxcf->gf_cfg; const int f_w = cm->width; const int f_h = cm->height; int i; const int is_intra_only = rc->frames_since_key == 0; cpi->ppi->internal_altref_allowed = (gf_cfg->gf_max_pyr_height > 1); // Reset the GF group data structures unless this is a key // frame in which case it will already have been done. if (!is_intra_only) { av1_zero(cpi->ppi->gf_group); cpi->gf_frame_index = 0; } GF_GROUP_STATS gf_stats; accumulate_gop_stats(cpi, is_intra_only, f_w, f_h, &next_frame, start_pos, &gf_stats, &i); const int can_disable_arf = !gf_cfg->gf_min_pyr_height; // TODO(any): set cpi->ppi->internal_altref_allowed accordingly; int use_alt_ref = av1_check_use_arf(cpi->third_pass_ctx); if (use_alt_ref == 0 && !can_disable_arf) return -1; if (use_alt_ref) { gf_group->max_layer_depth_allowed = gf_cfg->gf_max_pyr_height; } else { gf_group->max_layer_depth_allowed = 0; } update_gop_length(rc, p_rc, i, is_final_pass); // Set up the structure of this Group-Of-Pictures (same as GF_GROUP) av1_gop_setup_structure(cpi); set_gop_bits_boost(cpi, i, is_intra_only, is_final_pass, use_alt_ref, 0, start_pos, &gf_stats); frame_params->frame_type = cpi->third_pass_ctx->frame_info[0].frame_type; frame_params->show_frame = cpi->third_pass_ctx->frame_info[0].is_show_frame; return 0; } // #define FIXED_ARF_BITS #ifdef FIXED_ARF_BITS #define ARF_BITS_FRACTION 0.75 #endif void av1_gop_bit_allocation(const AV1_COMP *cpi, RATE_CONTROL *const rc, GF_GROUP *gf_group, int is_key_frame, int use_arf, int64_t gf_group_bits) { PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; // Calculate the extra bits to be used for boosted frame(s) #ifdef FIXED_ARF_BITS int gf_arf_bits = (int)(ARF_BITS_FRACTION * gf_group_bits); #else int gf_arf_bits = calculate_boost_bits( p_rc->baseline_gf_interval - (rc->frames_since_key == 0), p_rc->gfu_boost, gf_group_bits); #endif gf_arf_bits = adjust_boost_bits_for_target_level(cpi, rc, gf_arf_bits, gf_group_bits, 1); // Allocate bits to each of the frames in the GF group. allocate_gf_group_bits(gf_group, p_rc, rc, gf_group_bits, gf_arf_bits, is_key_frame, use_arf); } // Minimum % intra coding observed in first pass (1.0 = 100%) #define MIN_INTRA_LEVEL 0.25 // Minimum ratio between the % of intra coding and inter coding in the first // pass after discounting neutral blocks (discounting neutral blocks in this // way helps catch scene cuts in clips with very flat areas or letter box // format clips with image padding. #define INTRA_VS_INTER_THRESH 2.0 // Hard threshold where the first pass chooses intra for almost all blocks. // In such a case even if the frame is not a scene cut coding a key frame // may be a good option. #define VERY_LOW_INTER_THRESH 0.05 // Maximum threshold for the relative ratio of intra error score vs best // inter error score. #define KF_II_ERR_THRESHOLD 1.9 // In real scene cuts there is almost always a sharp change in the intra // or inter error score. #define ERR_CHANGE_THRESHOLD 0.4 // For real scene cuts we expect an improvment in the intra inter error // ratio in the next frame. #define II_IMPROVEMENT_THRESHOLD 3.5 #define KF_II_MAX 128.0 // Intra / Inter threshold very low #define VERY_LOW_II 1.5 // Clean slide transitions we expect a sharp single frame spike in error. #define ERROR_SPIKE 5.0 // Slide show transition detection. // Tests for case where there is very low error either side of the current frame // but much higher just for this frame. This can help detect key frames in // slide shows even where the slides are pictures of different sizes. // Also requires that intra and inter errors are very similar to help eliminate // harmful false positives. // It will not help if the transition is a fade or other multi-frame effect. static int slide_transition(const FIRSTPASS_STATS *this_frame, const FIRSTPASS_STATS *last_frame, const FIRSTPASS_STATS *next_frame) { return (this_frame->intra_error < (this_frame->coded_error * VERY_LOW_II)) && (this_frame->coded_error > (last_frame->coded_error * ERROR_SPIKE)) && (this_frame->coded_error > (next_frame->coded_error * ERROR_SPIKE)); } // Threshold for use of the lagging second reference frame. High second ref // usage may point to a transient event like a flash or occlusion rather than // a real scene cut. // We adapt the threshold based on number of frames in this key-frame group so // far. static double get_second_ref_usage_thresh(int frame_count_so_far) { const int adapt_upto = 32; const double min_second_ref_usage_thresh = 0.085; const double second_ref_usage_thresh_max_delta = 0.035; if (frame_count_so_far >= adapt_upto) { return min_second_ref_usage_thresh + second_ref_usage_thresh_max_delta; } return min_second_ref_usage_thresh + ((double)frame_count_so_far / (adapt_upto - 1)) * second_ref_usage_thresh_max_delta; } static int test_candidate_kf(const FIRSTPASS_INFO *firstpass_info, int this_stats_index, int frame_count_so_far, enum aom_rc_mode rc_mode, int scenecut_mode, int num_mbs) { const FIRSTPASS_STATS *last_stats = av1_firstpass_info_peek(firstpass_info, this_stats_index - 1); const FIRSTPASS_STATS *this_stats = av1_firstpass_info_peek(firstpass_info, this_stats_index); const FIRSTPASS_STATS *next_stats = av1_firstpass_info_peek(firstpass_info, this_stats_index + 1); if (last_stats == NULL || this_stats == NULL || next_stats == NULL) { return 0; } int is_viable_kf = 0; double pcnt_intra = 1.0 - this_stats->pcnt_inter; double modified_pcnt_inter = this_stats->pcnt_inter - this_stats->pcnt_neutral; const double second_ref_usage_thresh = get_second_ref_usage_thresh(frame_count_so_far); int frames_to_test_after_candidate_key = SCENE_CUT_KEY_TEST_INTERVAL; int count_for_tolerable_prediction = 3; // We do "-1" because the candidate key is not counted. int stats_after_this_stats = av1_firstpass_info_future_count(firstpass_info, this_stats_index) - 1; if (scenecut_mode == ENABLE_SCENECUT_MODE_1) { if (stats_after_this_stats < 3) { return 0; } else { frames_to_test_after_candidate_key = 3; count_for_tolerable_prediction = 1; } } // Make sure we have enough stats after the candidate key. frames_to_test_after_candidate_key = AOMMIN(frames_to_test_after_candidate_key, stats_after_this_stats); // Does the frame satisfy the primary criteria of a key frame? // See above for an explanation of the test criteria. // If so, then examine how well it predicts subsequent frames. if (IMPLIES(rc_mode == AOM_Q, frame_count_so_far >= 3) && (this_stats->pcnt_second_ref < second_ref_usage_thresh) && (next_stats->pcnt_second_ref < second_ref_usage_thresh) && ((this_stats->pcnt_inter < VERY_LOW_INTER_THRESH) || slide_transition(this_stats, last_stats, next_stats) || ((pcnt_intra > MIN_INTRA_LEVEL) && (pcnt_intra > (INTRA_VS_INTER_THRESH * modified_pcnt_inter)) && ((this_stats->intra_error / DOUBLE_DIVIDE_CHECK(this_stats->coded_error)) < KF_II_ERR_THRESHOLD) && ((fabs(last_stats->coded_error - this_stats->coded_error) / DOUBLE_DIVIDE_CHECK(this_stats->coded_error) > ERR_CHANGE_THRESHOLD) || (fabs(last_stats->intra_error - this_stats->intra_error) / DOUBLE_DIVIDE_CHECK(this_stats->intra_error) > ERR_CHANGE_THRESHOLD) || ((next_stats->intra_error / DOUBLE_DIVIDE_CHECK(next_stats->coded_error)) > II_IMPROVEMENT_THRESHOLD))))) { int i; double boost_score = 0.0; double old_boost_score = 0.0; double decay_accumulator = 1.0; // Examine how well the key frame predicts subsequent frames. for (i = 1; i <= frames_to_test_after_candidate_key; ++i) { // Get the next frame details const FIRSTPASS_STATS *local_next_frame = av1_firstpass_info_peek(firstpass_info, this_stats_index + i); double next_iiratio = (BOOST_FACTOR * local_next_frame->intra_error / DOUBLE_DIVIDE_CHECK(local_next_frame->coded_error)); if (next_iiratio > KF_II_MAX) next_iiratio = KF_II_MAX; // Cumulative effect of decay in prediction quality. if (local_next_frame->pcnt_inter > 0.85) decay_accumulator *= local_next_frame->pcnt_inter; else decay_accumulator *= (0.85 + local_next_frame->pcnt_inter) / 2.0; // Keep a running total. boost_score += (decay_accumulator * next_iiratio); // Test various breakout clauses. // TODO(any): Test of intra error should be normalized to an MB. if ((local_next_frame->pcnt_inter < 0.05) || (next_iiratio < 1.5) || (((local_next_frame->pcnt_inter - local_next_frame->pcnt_neutral) < 0.20) && (next_iiratio < 3.0)) || ((boost_score - old_boost_score) < 3.0) || (local_next_frame->intra_error < (200.0 / (double)num_mbs))) { break; } old_boost_score = boost_score; } // If there is tolerable prediction for at least the next 3 frames then // break out else discard this potential key frame and move on if (boost_score > 30.0 && (i > count_for_tolerable_prediction)) { is_viable_kf = 1; } else { is_viable_kf = 0; } } return is_viable_kf; } #define FRAMES_TO_CHECK_DECAY 8 #define KF_MIN_FRAME_BOOST 80.0 #define KF_MAX_FRAME_BOOST 128.0 #define MIN_KF_BOOST 600 // Minimum boost for non-static KF interval #define MAX_KF_BOOST 3200 #define MIN_STATIC_KF_BOOST 5400 // Minimum boost for static KF interval static int detect_app_forced_key(AV1_COMP *cpi) { int num_frames_to_app_forced_key = is_forced_keyframe_pending( cpi->ppi->lookahead, cpi->ppi->lookahead->max_sz, cpi->compressor_stage); return num_frames_to_app_forced_key; } static int get_projected_kf_boost(AV1_COMP *cpi) { /* * If num_stats_used_for_kf_boost >= frames_to_key, then * all stats needed for prior boost calculation are available. * Hence projecting the prior boost is not needed in this cases. */ if (cpi->ppi->p_rc.num_stats_used_for_kf_boost >= cpi->rc.frames_to_key) return cpi->ppi->p_rc.kf_boost; // Get the current tpl factor (number of frames = frames_to_key). double tpl_factor = av1_get_kf_boost_projection_factor(cpi->rc.frames_to_key); // Get the tpl factor when number of frames = num_stats_used_for_kf_boost. double tpl_factor_num_stats = av1_get_kf_boost_projection_factor( cpi->ppi->p_rc.num_stats_used_for_kf_boost); int projected_kf_boost = (int)rint((tpl_factor * cpi->ppi->p_rc.kf_boost) / tpl_factor_num_stats); return projected_kf_boost; } /*!\brief Determine the location of the next key frame * * \ingroup gf_group_algo * This function decides the placement of the next key frame when a * scenecut is detected or the maximum key frame distance is reached. * * \param[in] cpi Top-level encoder structure * \param[in] firstpass_info struct for firstpass info * \param[in] num_frames_to_detect_scenecut Maximum lookahead frames. * \param[in] search_start_idx the start index for searching key frame. * Set it to one if we already know the * current frame is key frame. Otherwise, * set it to zero. * * \return Number of frames to the next key including the current frame. */ static int define_kf_interval(AV1_COMP *cpi, const FIRSTPASS_INFO *firstpass_info, int num_frames_to_detect_scenecut, int search_start_idx) { const TWO_PASS *const twopass = &cpi->ppi->twopass; const RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; const AV1EncoderConfig *const oxcf = &cpi->oxcf; const KeyFrameCfg *const kf_cfg = &oxcf->kf_cfg; double recent_loop_decay[FRAMES_TO_CHECK_DECAY]; double decay_accumulator = 1.0; int i = 0, j; int frames_to_key = search_start_idx; int frames_since_key = rc->frames_since_key + 1; int scenecut_detected = 0; int num_frames_to_next_key = detect_app_forced_key(cpi); if (num_frames_to_detect_scenecut == 0) { if (num_frames_to_next_key != -1) return num_frames_to_next_key; else return rc->frames_to_key; } if (num_frames_to_next_key != -1) num_frames_to_detect_scenecut = AOMMIN(num_frames_to_detect_scenecut, num_frames_to_next_key); // Initialize the decay rates for the recent frames to check for (j = 0; j < FRAMES_TO_CHECK_DECAY; ++j) recent_loop_decay[j] = 1.0; i = 0; const int num_mbs = (oxcf->resize_cfg.resize_mode != RESIZE_NONE) ? cpi->initial_mbs : cpi->common.mi_params.MBs; const int future_stats_count = av1_firstpass_info_future_count(firstpass_info, 0); while (frames_to_key < future_stats_count && frames_to_key < num_frames_to_detect_scenecut) { // Provided that we are not at the end of the file... if ((cpi->ppi->p_rc.enable_scenecut_detection > 0) && kf_cfg->auto_key && frames_to_key + 1 < future_stats_count) { double loop_decay_rate; // Check for a scene cut. if (frames_since_key >= kf_cfg->key_freq_min) { scenecut_detected = test_candidate_kf( &twopass->firstpass_info, frames_to_key, frames_since_key, oxcf->rc_cfg.mode, cpi->ppi->p_rc.enable_scenecut_detection, num_mbs); if (scenecut_detected) { break; } } // How fast is the prediction quality decaying? const FIRSTPASS_STATS *next_stats = av1_firstpass_info_peek(firstpass_info, frames_to_key + 1); loop_decay_rate = get_prediction_decay_rate(next_stats); // We want to know something about the recent past... rather than // as used elsewhere where we are concerned with decay in prediction // quality since the last GF or KF. recent_loop_decay[i % FRAMES_TO_CHECK_DECAY] = loop_decay_rate; decay_accumulator = 1.0; for (j = 0; j < FRAMES_TO_CHECK_DECAY; ++j) decay_accumulator *= recent_loop_decay[j]; // Special check for transition or high motion followed by a // static scene. if (frames_since_key >= kf_cfg->key_freq_min) { scenecut_detected = detect_transition_to_still( firstpass_info, frames_to_key + 1, rc->min_gf_interval, i, kf_cfg->key_freq_max - i, loop_decay_rate, decay_accumulator); if (scenecut_detected) { // In the case of transition followed by a static scene, the key frame // could be a good predictor for the following frames, therefore we // do not use an arf. p_rc->use_arf_in_this_kf_group = 0; break; } } // Step on to the next frame. ++frames_to_key; ++frames_since_key; // If we don't have a real key frame within the next two // key_freq_max intervals then break out of the loop. if (frames_to_key >= 2 * kf_cfg->key_freq_max) { break; } } else { ++frames_to_key; ++frames_since_key; } ++i; } if (cpi->ppi->lap_enabled && !scenecut_detected) frames_to_key = num_frames_to_next_key; return frames_to_key; } static double get_kf_group_avg_error(TWO_PASS *twopass, TWO_PASS_FRAME *twopass_frame, const FIRSTPASS_STATS *first_frame, const FIRSTPASS_STATS *start_position, int frames_to_key) { FIRSTPASS_STATS cur_frame = *first_frame; int num_frames, i; double kf_group_avg_error = 0.0; reset_fpf_position(twopass_frame, start_position); for (i = 0; i < frames_to_key; ++i) { kf_group_avg_error += cur_frame.coded_error; if (EOF == input_stats(twopass, twopass_frame, &cur_frame)) break; } num_frames = i + 1; num_frames = AOMMIN(num_frames, frames_to_key); kf_group_avg_error = kf_group_avg_error / num_frames; return (kf_group_avg_error); } static int64_t get_kf_group_bits(AV1_COMP *cpi, double kf_group_err, double kf_group_avg_error) { RATE_CONTROL *const rc = &cpi->rc; TWO_PASS *const twopass = &cpi->ppi->twopass; int64_t kf_group_bits; if (cpi->ppi->lap_enabled) { kf_group_bits = (int64_t)rc->frames_to_key * rc->avg_frame_bandwidth; if (cpi->oxcf.rc_cfg.vbr_corpus_complexity_lap) { double vbr_corpus_complexity_lap = cpi->oxcf.rc_cfg.vbr_corpus_complexity_lap / 10.0; /* Get the average corpus complexity of the frame */ kf_group_bits = (int64_t)( kf_group_bits * (kf_group_avg_error / vbr_corpus_complexity_lap)); } } else { kf_group_bits = (int64_t)(twopass->bits_left * (kf_group_err / twopass->modified_error_left)); } return kf_group_bits; } static int calc_avg_stats(AV1_COMP *cpi, FIRSTPASS_STATS *avg_frame_stat) { RATE_CONTROL *const rc = &cpi->rc; TWO_PASS *const twopass = &cpi->ppi->twopass; FIRSTPASS_STATS cur_frame; av1_zero(cur_frame); int num_frames = 0; // Accumulate total stat using available number of stats. for (num_frames = 0; num_frames < (rc->frames_to_key - 1); ++num_frames) { if (EOF == input_stats(twopass, &cpi->twopass_frame, &cur_frame)) break; av1_accumulate_stats(avg_frame_stat, &cur_frame); } if (num_frames < 2) { return num_frames; } // Average the total stat avg_frame_stat->weight = avg_frame_stat->weight / num_frames; avg_frame_stat->intra_error = avg_frame_stat->intra_error / num_frames; avg_frame_stat->frame_avg_wavelet_energy = avg_frame_stat->frame_avg_wavelet_energy / num_frames; avg_frame_stat->coded_error = avg_frame_stat->coded_error / num_frames; avg_frame_stat->sr_coded_error = avg_frame_stat->sr_coded_error / num_frames; avg_frame_stat->pcnt_inter = avg_frame_stat->pcnt_inter / num_frames; avg_frame_stat->pcnt_motion = avg_frame_stat->pcnt_motion / num_frames; avg_frame_stat->pcnt_second_ref = avg_frame_stat->pcnt_second_ref / num_frames; avg_frame_stat->pcnt_neutral = avg_frame_stat->pcnt_neutral / num_frames; avg_frame_stat->intra_skip_pct = avg_frame_stat->intra_skip_pct / num_frames; avg_frame_stat->inactive_zone_rows = avg_frame_stat->inactive_zone_rows / num_frames; avg_frame_stat->inactive_zone_cols = avg_frame_stat->inactive_zone_cols / num_frames; avg_frame_stat->MVr = avg_frame_stat->MVr / num_frames; avg_frame_stat->mvr_abs = avg_frame_stat->mvr_abs / num_frames; avg_frame_stat->MVc = avg_frame_stat->MVc / num_frames; avg_frame_stat->mvc_abs = avg_frame_stat->mvc_abs / num_frames; avg_frame_stat->MVrv = avg_frame_stat->MVrv / num_frames; avg_frame_stat->MVcv = avg_frame_stat->MVcv / num_frames; avg_frame_stat->mv_in_out_count = avg_frame_stat->mv_in_out_count / num_frames; avg_frame_stat->new_mv_count = avg_frame_stat->new_mv_count / num_frames; avg_frame_stat->count = avg_frame_stat->count / num_frames; avg_frame_stat->duration = avg_frame_stat->duration / num_frames; return num_frames; } static double get_kf_boost_score(AV1_COMP *cpi, double kf_raw_err, double *zero_motion_accumulator, double *sr_accumulator, int use_avg_stat) { RATE_CONTROL *const rc = &cpi->rc; TWO_PASS *const twopass = &cpi->ppi->twopass; FRAME_INFO *const frame_info = &cpi->frame_info; FIRSTPASS_STATS frame_stat; av1_zero(frame_stat); int i = 0, num_stat_used = 0; double boost_score = 0.0; const double kf_max_boost = cpi->oxcf.rc_cfg.mode == AOM_Q ? AOMMIN(AOMMAX(rc->frames_to_key * 2.0, KF_MIN_FRAME_BOOST), KF_MAX_FRAME_BOOST) : KF_MAX_FRAME_BOOST; // Calculate the average using available number of stats. if (use_avg_stat) num_stat_used = calc_avg_stats(cpi, &frame_stat); for (i = num_stat_used; i < (rc->frames_to_key - 1); ++i) { if (!use_avg_stat && EOF == input_stats(twopass, &cpi->twopass_frame, &frame_stat)) break; // Monitor for static sections. // For the first frame in kf group, the second ref indicator is invalid. if (i > 0) { *zero_motion_accumulator = AOMMIN(*zero_motion_accumulator, get_zero_motion_factor(&frame_stat)); } else { *zero_motion_accumulator = frame_stat.pcnt_inter - frame_stat.pcnt_motion; } // Not all frames in the group are necessarily used in calculating boost. if ((*sr_accumulator < (kf_raw_err * 1.50)) && (i <= rc->max_gf_interval * 2)) { double frame_boost; double zm_factor; // Factor 0.75-1.25 based on how much of frame is static. zm_factor = (0.75 + (*zero_motion_accumulator / 2.0)); if (i < 2) *sr_accumulator = 0.0; frame_boost = calc_kf_frame_boost(&cpi->ppi->p_rc, frame_info, &frame_stat, sr_accumulator, kf_max_boost); boost_score += frame_boost * zm_factor; } } return boost_score; } /*!\brief Interval(in seconds) to clip key-frame distance to in LAP. */ #define MAX_KF_BITS_INTERVAL_SINGLE_PASS 5 /*!\brief Determine the next key frame group * * \ingroup gf_group_algo * This function decides the placement of the next key frame, and * calculates the bit allocation of the KF group and the keyframe itself. * * \param[in] cpi Top-level encoder structure * \param[in] this_frame Pointer to first pass stats */ static void find_next_key_frame(AV1_COMP *cpi, FIRSTPASS_STATS *this_frame) { RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; TWO_PASS *const twopass = &cpi->ppi->twopass; GF_GROUP *const gf_group = &cpi->ppi->gf_group; FRAME_INFO *const frame_info = &cpi->frame_info; AV1_COMMON *const cm = &cpi->common; CurrentFrame *const current_frame = &cm->current_frame; const AV1EncoderConfig *const oxcf = &cpi->oxcf; const KeyFrameCfg *const kf_cfg = &oxcf->kf_cfg; const FIRSTPASS_STATS first_frame = *this_frame; FIRSTPASS_STATS next_frame; const FIRSTPASS_INFO *firstpass_info = &twopass->firstpass_info; av1_zero(next_frame); rc->frames_since_key = 0; // Use arfs if possible. p_rc->use_arf_in_this_kf_group = is_altref_enabled( oxcf->gf_cfg.lag_in_frames, oxcf->gf_cfg.enable_auto_arf); // Reset the GF group data structures. av1_zero(*gf_group); cpi->gf_frame_index = 0; // KF is always a GF so clear frames till next gf counter. rc->frames_till_gf_update_due = 0; if (has_no_stats_stage(cpi)) { int num_frames_to_app_forced_key = detect_app_forced_key(cpi); p_rc->this_key_frame_forced = current_frame->frame_number != 0 && rc->frames_to_key == 0; if (num_frames_to_app_forced_key != -1) rc->frames_to_key = num_frames_to_app_forced_key; else rc->frames_to_key = AOMMAX(1, kf_cfg->key_freq_max); correct_frames_to_key(cpi); p_rc->kf_boost = DEFAULT_KF_BOOST; gf_group->update_type[0] = KF_UPDATE; return; } int i; const FIRSTPASS_STATS *const start_position = cpi->twopass_frame.stats_in; int kf_bits = 0; double zero_motion_accumulator = 1.0; double boost_score = 0.0; double kf_raw_err = 0.0; double kf_mod_err = 0.0; double sr_accumulator = 0.0; double kf_group_avg_error = 0.0; int frames_to_key, frames_to_key_clipped = INT_MAX; int64_t kf_group_bits_clipped = INT64_MAX; // Is this a forced key frame by interval. p_rc->this_key_frame_forced = p_rc->next_key_frame_forced; twopass->kf_group_bits = 0; // Total bits available to kf group twopass->kf_group_error_left = 0; // Group modified error score. kf_raw_err = this_frame->intra_error; kf_mod_err = calculate_modified_err(frame_info, twopass, oxcf, this_frame); // We assume the current frame is a key frame and we are looking for the next // key frame. Therefore search_start_idx = 1 frames_to_key = define_kf_interval(cpi, firstpass_info, kf_cfg->key_freq_max, /*search_start_idx=*/1); if (frames_to_key != -1) { rc->frames_to_key = AOMMIN(kf_cfg->key_freq_max, frames_to_key); } else { rc->frames_to_key = kf_cfg->key_freq_max; } if (cpi->ppi->lap_enabled) correct_frames_to_key(cpi); // If there is a max kf interval set by the user we must obey it. // We already breakout of the loop above at 2x max. // This code centers the extra kf if the actual natural interval // is between 1x and 2x. if (kf_cfg->auto_key && rc->frames_to_key > kf_cfg->key_freq_max) { FIRSTPASS_STATS tmp_frame = first_frame; rc->frames_to_key /= 2; // Reset to the start of the group. reset_fpf_position(&cpi->twopass_frame, start_position); // Rescan to get the correct error data for the forced kf group. for (i = 0; i < rc->frames_to_key; ++i) { if (EOF == input_stats(twopass, &cpi->twopass_frame, &tmp_frame)) break; } p_rc->next_key_frame_forced = 1; } else if ((cpi->twopass_frame.stats_in == twopass->stats_buf_ctx->stats_in_end && is_stat_consumption_stage_twopass(cpi)) || rc->frames_to_key >= kf_cfg->key_freq_max) { p_rc->next_key_frame_forced = 1; } else { p_rc->next_key_frame_forced = 0; } double kf_group_err = 0; for (i = 0; i < rc->frames_to_key; ++i) { const FIRSTPASS_STATS *this_stats = av1_firstpass_info_peek(&twopass->firstpass_info, i); if (this_stats != NULL) { // Accumulate kf group error. kf_group_err += calculate_modified_err_new( frame_info, &firstpass_info->total_stats, this_stats, oxcf->rc_cfg.vbrbias, twopass->modified_error_min, twopass->modified_error_max); ++p_rc->num_stats_used_for_kf_boost; } } // Calculate the number of bits that should be assigned to the kf group. if ((twopass->bits_left > 0 && twopass->modified_error_left > 0.0) || (cpi->ppi->lap_enabled && oxcf->rc_cfg.mode != AOM_Q)) { // Maximum number of bits for a single normal frame (not key frame). const int max_bits = frame_max_bits(rc, oxcf); // Maximum number of bits allocated to the key frame group. int64_t max_grp_bits; if (oxcf->rc_cfg.vbr_corpus_complexity_lap) { kf_group_avg_error = get_kf_group_avg_error(twopass, &cpi->twopass_frame, &first_frame, start_position, rc->frames_to_key); } // Default allocation based on bits left and relative // complexity of the section. twopass->kf_group_bits = get_kf_group_bits(cpi, kf_group_err, kf_group_avg_error); // Clip based on maximum per frame rate defined by the user. max_grp_bits = (int64_t)max_bits * (int64_t)rc->frames_to_key; if (twopass->kf_group_bits > max_grp_bits) twopass->kf_group_bits = max_grp_bits; } else { twopass->kf_group_bits = 0; } twopass->kf_group_bits = AOMMAX(0, twopass->kf_group_bits); if (cpi->ppi->lap_enabled) { // In the case of single pass based on LAP, frames to key may have an // inaccurate value, and hence should be clipped to an appropriate // interval. frames_to_key_clipped = (int)(MAX_KF_BITS_INTERVAL_SINGLE_PASS * cpi->framerate); // This variable calculates the bits allocated to kf_group with a clipped // frames_to_key. if (rc->frames_to_key > frames_to_key_clipped) { kf_group_bits_clipped = (int64_t)((double)twopass->kf_group_bits * frames_to_key_clipped / rc->frames_to_key); } } // Reset the first pass file position. reset_fpf_position(&cpi->twopass_frame, start_position); // Scan through the kf group collating various stats used to determine // how many bits to spend on it. boost_score = get_kf_boost_score(cpi, kf_raw_err, &zero_motion_accumulator, &sr_accumulator, 0); reset_fpf_position(&cpi->twopass_frame, start_position); // Store the zero motion percentage twopass->kf_zeromotion_pct = (int)(zero_motion_accumulator * 100.0); // Calculate a section intra ratio used in setting max loop filter. twopass->section_intra_rating = calculate_section_intra_ratio( start_position, twopass->stats_buf_ctx->stats_in_end, rc->frames_to_key); p_rc->kf_boost = (int)boost_score; if (cpi->ppi->lap_enabled) { if (oxcf->rc_cfg.mode == AOM_Q) { p_rc->kf_boost = get_projected_kf_boost(cpi); } else { // TODO(any): Explore using average frame stats for AOM_Q as well. boost_score = get_kf_boost_score( cpi, kf_raw_err, &zero_motion_accumulator, &sr_accumulator, 1); reset_fpf_position(&cpi->twopass_frame, start_position); p_rc->kf_boost += (int)boost_score; } } // Special case for static / slide show content but don't apply // if the kf group is very short. if ((zero_motion_accumulator > STATIC_KF_GROUP_FLOAT_THRESH) && (rc->frames_to_key > 8)) { p_rc->kf_boost = AOMMAX(p_rc->kf_boost, MIN_STATIC_KF_BOOST); } else { // Apply various clamps for min and max boost p_rc->kf_boost = AOMMAX(p_rc->kf_boost, (rc->frames_to_key * 3)); p_rc->kf_boost = AOMMAX(p_rc->kf_boost, MIN_KF_BOOST); #ifdef STRICT_RC p_rc->kf_boost = AOMMIN(p_rc->kf_boost, MAX_KF_BOOST); #endif } // Work out how many bits to allocate for the key frame itself. // In case of LAP enabled for VBR, if the frames_to_key value is // very high, we calculate the bits based on a clipped value of // frames_to_key. kf_bits = calculate_boost_bits( AOMMIN(rc->frames_to_key, frames_to_key_clipped) - 1, p_rc->kf_boost, AOMMIN(twopass->kf_group_bits, kf_group_bits_clipped)); // printf("kf boost = %d kf_bits = %d kf_zeromotion_pct = %d\n", // p_rc->kf_boost, // kf_bits, twopass->kf_zeromotion_pct); kf_bits = adjust_boost_bits_for_target_level(cpi, rc, kf_bits, twopass->kf_group_bits, 0); twopass->kf_group_bits -= kf_bits; // Save the bits to spend on the key frame. gf_group->bit_allocation[0] = kf_bits; gf_group->update_type[0] = KF_UPDATE; // Note the total error score of the kf group minus the key frame itself. if (cpi->ppi->lap_enabled) // As we don't have enough stats to know the actual error of the group, // we assume the complexity of each frame to be equal to 1, and set the // error as the number of frames in the group(minus the keyframe). twopass->kf_group_error_left = (double)(rc->frames_to_key - 1); else twopass->kf_group_error_left = kf_group_err - kf_mod_err; // Adjust the count of total modified error left. // The count of bits left is adjusted elsewhere based on real coded frame // sizes. twopass->modified_error_left -= kf_group_err; } #define ARF_STATS_OUTPUT 0 #if ARF_STATS_OUTPUT unsigned int arf_count = 0; #endif static int get_section_target_bandwidth(AV1_COMP *cpi) { AV1_COMMON *const cm = &cpi->common; CurrentFrame *const current_frame = &cm->current_frame; RATE_CONTROL *const rc = &cpi->rc; TWO_PASS *const twopass = &cpi->ppi->twopass; int section_target_bandwidth; const int frames_left = (int)(twopass->stats_buf_ctx->total_stats->count - current_frame->frame_number); if (cpi->ppi->lap_enabled) section_target_bandwidth = (int)rc->avg_frame_bandwidth; else section_target_bandwidth = (int)(twopass->bits_left / frames_left); return section_target_bandwidth; } static INLINE void set_twopass_params_based_on_fp_stats( AV1_COMP *cpi, const FIRSTPASS_STATS *this_frame_ptr) { if (this_frame_ptr == NULL) return; TWO_PASS_FRAME *twopass_frame = &cpi->twopass_frame; // The multiplication by 256 reverses a scaling factor of (>> 8) // applied when combining MB error values for the frame. twopass_frame->mb_av_energy = log1p(this_frame_ptr->intra_error); const FIRSTPASS_STATS *const total_stats = cpi->ppi->twopass.stats_buf_ctx->total_stats; if (is_fp_wavelet_energy_invalid(total_stats) == 0) { twopass_frame->frame_avg_haar_energy = log1p(this_frame_ptr->frame_avg_wavelet_energy); } // Set the frame content type flag. if (this_frame_ptr->intra_skip_pct >= FC_ANIMATION_THRESH) twopass_frame->fr_content_type = FC_GRAPHICS_ANIMATION; else twopass_frame->fr_content_type = FC_NORMAL; } static void process_first_pass_stats(AV1_COMP *cpi, FIRSTPASS_STATS *this_frame) { AV1_COMMON *const cm = &cpi->common; CurrentFrame *const current_frame = &cm->current_frame; RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; TWO_PASS *const twopass = &cpi->ppi->twopass; FIRSTPASS_STATS *total_stats = twopass->stats_buf_ctx->total_stats; if (cpi->oxcf.rc_cfg.mode != AOM_Q && current_frame->frame_number == 0 && cpi->gf_frame_index == 0 && total_stats && twopass->stats_buf_ctx->total_left_stats) { if (cpi->ppi->lap_enabled) { /* * Accumulate total_stats using available limited number of stats, * and assign it to total_left_stats. */ *twopass->stats_buf_ctx->total_left_stats = *total_stats; } // Special case code for first frame. const int section_target_bandwidth = get_section_target_bandwidth(cpi); const double section_length = twopass->stats_buf_ctx->total_left_stats->count; const double section_error = twopass->stats_buf_ctx->total_left_stats->coded_error / section_length; const double section_intra_skip = twopass->stats_buf_ctx->total_left_stats->intra_skip_pct / section_length; const double section_inactive_zone = (twopass->stats_buf_ctx->total_left_stats->inactive_zone_rows * 2) / ((double)cm->mi_params.mb_rows * section_length); const int tmp_q = get_twopass_worst_quality( cpi, section_error, section_intra_skip + section_inactive_zone, section_target_bandwidth); rc->active_worst_quality = tmp_q; rc->ni_av_qi = tmp_q; p_rc->last_q[INTER_FRAME] = tmp_q; p_rc->avg_q = av1_convert_qindex_to_q(tmp_q, cm->seq_params->bit_depth); p_rc->avg_frame_qindex[INTER_FRAME] = tmp_q; p_rc->last_q[KEY_FRAME] = (tmp_q + cpi->oxcf.rc_cfg.best_allowed_q) / 2; p_rc->avg_frame_qindex[KEY_FRAME] = p_rc->last_q[KEY_FRAME]; } if (cpi->twopass_frame.stats_in < twopass->stats_buf_ctx->stats_in_end) { *this_frame = *cpi->twopass_frame.stats_in; ++cpi->twopass_frame.stats_in; } set_twopass_params_based_on_fp_stats(cpi, this_frame); } static void setup_target_rate(AV1_COMP *cpi) { RATE_CONTROL *const rc = &cpi->rc; GF_GROUP *const gf_group = &cpi->ppi->gf_group; int target_rate = gf_group->bit_allocation[cpi->gf_frame_index]; if (has_no_stats_stage(cpi)) { av1_rc_set_frame_target(cpi, target_rate, cpi->common.width, cpi->common.height); } rc->base_frame_target = target_rate; } void av1_mark_flashes(FIRSTPASS_STATS *first_stats, FIRSTPASS_STATS *last_stats) { FIRSTPASS_STATS *this_stats = first_stats, *next_stats; while (this_stats < last_stats - 1) { next_stats = this_stats + 1; if (next_stats->pcnt_second_ref > next_stats->pcnt_inter && next_stats->pcnt_second_ref >= 0.5) { this_stats->is_flash = 1; } else { this_stats->is_flash = 0; } this_stats = next_stats; } // We always treat the last one as none flash. if (last_stats - 1 >= first_stats) { (last_stats - 1)->is_flash = 0; } } // Smooth-out the noise variance so it is more stable // Returns 0 on success, -1 on memory allocation failure. // TODO(bohanli): Use a better low-pass filter than averaging static int smooth_filter_noise(FIRSTPASS_STATS *first_stats, FIRSTPASS_STATS *last_stats) { int len = (int)(last_stats - first_stats); double *smooth_noise = aom_malloc(len * sizeof(*smooth_noise)); if (!smooth_noise) return -1; for (int i = 0; i < len; i++) { double total_noise = 0; double total_wt = 0; for (int j = -HALF_FILT_LEN; j <= HALF_FILT_LEN; j++) { int idx = AOMMIN(AOMMAX(i + j, 0), len - 1); if (first_stats[idx].is_flash) continue; total_noise += first_stats[idx].noise_var; total_wt += 1.0; } if (total_wt > 0.01) { total_noise /= total_wt; } else { total_noise = first_stats[i].noise_var; } smooth_noise[i] = total_noise; } for (int i = 0; i < len; i++) { first_stats[i].noise_var = smooth_noise[i]; } aom_free(smooth_noise); return 0; } // Estimate the noise variance of each frame from the first pass stats void av1_estimate_noise(FIRSTPASS_STATS *first_stats, FIRSTPASS_STATS *last_stats, struct aom_internal_error_info *error_info) { FIRSTPASS_STATS *this_stats, *next_stats; double C1, C2, C3, noise; for (this_stats = first_stats + 2; this_stats < last_stats; this_stats++) { this_stats->noise_var = 0.0; // flashes tend to have high correlation of innovations, so ignore them. if (this_stats->is_flash || (this_stats - 1)->is_flash || (this_stats - 2)->is_flash) continue; C1 = (this_stats - 1)->intra_error * (this_stats->intra_error - this_stats->coded_error); C2 = (this_stats - 2)->intra_error * ((this_stats - 1)->intra_error - (this_stats - 1)->coded_error); C3 = (this_stats - 2)->intra_error * (this_stats->intra_error - this_stats->sr_coded_error); if (C1 <= 0 || C2 <= 0 || C3 <= 0) continue; C1 = sqrt(C1); C2 = sqrt(C2); C3 = sqrt(C3); noise = (this_stats - 1)->intra_error - C1 * C2 / C3; noise = AOMMAX(noise, 0.01); this_stats->noise_var = noise; } // Copy noise from the neighbor if the noise value is not trustworthy for (this_stats = first_stats + 2; this_stats < last_stats; this_stats++) { if (this_stats->is_flash || (this_stats - 1)->is_flash || (this_stats - 2)->is_flash) continue; if (this_stats->noise_var < 1.0) { int found = 0; // TODO(bohanli): consider expanding to two directions at the same time for (next_stats = this_stats + 1; next_stats < last_stats; next_stats++) { if (next_stats->is_flash || (next_stats - 1)->is_flash || (next_stats - 2)->is_flash || next_stats->noise_var < 1.0) continue; found = 1; this_stats->noise_var = next_stats->noise_var; break; } if (found) continue; for (next_stats = this_stats - 1; next_stats >= first_stats + 2; next_stats--) { if (next_stats->is_flash || (next_stats - 1)->is_flash || (next_stats - 2)->is_flash || next_stats->noise_var < 1.0) continue; this_stats->noise_var = next_stats->noise_var; break; } } } // copy the noise if this is a flash for (this_stats = first_stats + 2; this_stats < last_stats; this_stats++) { if (this_stats->is_flash || (this_stats - 1)->is_flash || (this_stats - 2)->is_flash) { int found = 0; for (next_stats = this_stats + 1; next_stats < last_stats; next_stats++) { if (next_stats->is_flash || (next_stats - 1)->is_flash || (next_stats - 2)->is_flash) continue; found = 1; this_stats->noise_var = next_stats->noise_var; break; } if (found) continue; for (next_stats = this_stats - 1; next_stats >= first_stats + 2; next_stats--) { if (next_stats->is_flash || (next_stats - 1)->is_flash || (next_stats - 2)->is_flash) continue; this_stats->noise_var = next_stats->noise_var; break; } } } // if we are at the first 2 frames, copy the noise for (this_stats = first_stats; this_stats < first_stats + 2 && (first_stats + 2) < last_stats; this_stats++) { this_stats->noise_var = (first_stats + 2)->noise_var; } if (smooth_filter_noise(first_stats, last_stats) == -1) { aom_internal_error(error_info, AOM_CODEC_MEM_ERROR, "Error allocating buffers in smooth_filter_noise()"); } } // Estimate correlation coefficient of each frame with its previous frame. void av1_estimate_coeff(FIRSTPASS_STATS *first_stats, FIRSTPASS_STATS *last_stats) { FIRSTPASS_STATS *this_stats; for (this_stats = first_stats + 1; this_stats < last_stats; this_stats++) { const double C = sqrt(AOMMAX((this_stats - 1)->intra_error * (this_stats->intra_error - this_stats->coded_error), 0.001)); const double cor_coeff = C / AOMMAX((this_stats - 1)->intra_error - this_stats->noise_var, 0.001); this_stats->cor_coeff = cor_coeff * sqrt(AOMMAX((this_stats - 1)->intra_error - this_stats->noise_var, 0.001) / AOMMAX(this_stats->intra_error - this_stats->noise_var, 0.001)); // clip correlation coefficient. this_stats->cor_coeff = AOMMIN(AOMMAX(this_stats->cor_coeff, 0), 1); } first_stats->cor_coeff = 1.0; } void av1_get_second_pass_params(AV1_COMP *cpi, EncodeFrameParams *const frame_params, unsigned int frame_flags) { RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; TWO_PASS *const twopass = &cpi->ppi->twopass; GF_GROUP *const gf_group = &cpi->ppi->gf_group; const AV1EncoderConfig *const oxcf = &cpi->oxcf; if (cpi->use_ducky_encode && cpi->ducky_encode_info.frame_info.gop_mode == DUCKY_ENCODE_GOP_MODE_RCL) { frame_params->frame_type = gf_group->frame_type[cpi->gf_frame_index]; frame_params->show_frame = !(gf_group->update_type[cpi->gf_frame_index] == ARF_UPDATE || gf_group->update_type[cpi->gf_frame_index] == INTNL_ARF_UPDATE); if (cpi->gf_frame_index == 0) { av1_tf_info_reset(&cpi->ppi->tf_info); av1_tf_info_filtering(&cpi->ppi->tf_info, cpi, gf_group); } return; } const FIRSTPASS_STATS *const start_pos = cpi->twopass_frame.stats_in; int update_total_stats = 0; if (is_stat_consumption_stage(cpi) && !cpi->twopass_frame.stats_in) return; // Check forced key frames. const int frames_to_next_forced_key = detect_app_forced_key(cpi); if (frames_to_next_forced_key == 0) { rc->frames_to_key = 0; frame_flags &= FRAMEFLAGS_KEY; } else if (frames_to_next_forced_key > 0 && frames_to_next_forced_key < rc->frames_to_key) { rc->frames_to_key = frames_to_next_forced_key; } assert(cpi->twopass_frame.stats_in != NULL); const int update_type = gf_group->update_type[cpi->gf_frame_index]; frame_params->frame_type = gf_group->frame_type[cpi->gf_frame_index]; if (cpi->gf_frame_index < gf_group->size && !(frame_flags & FRAMEFLAGS_KEY)) { assert(cpi->gf_frame_index < gf_group->size); setup_target_rate(cpi); // If this is an arf frame then we dont want to read the stats file or // advance the input pointer as we already have what we need. if (update_type == ARF_UPDATE || update_type == INTNL_ARF_UPDATE) { const FIRSTPASS_STATS *const this_frame_ptr = read_frame_stats(twopass, &cpi->twopass_frame, gf_group->arf_src_offset[cpi->gf_frame_index]); set_twopass_params_based_on_fp_stats(cpi, this_frame_ptr); return; } } if (oxcf->rc_cfg.mode == AOM_Q) rc->active_worst_quality = oxcf->rc_cfg.cq_level; if (cpi->gf_frame_index == gf_group->size) { if (cpi->ppi->lap_enabled && cpi->ppi->p_rc.enable_scenecut_detection) { const int num_frames_to_detect_scenecut = MAX_GF_LENGTH_LAP + 1; const int frames_to_key = define_kf_interval( cpi, &twopass->firstpass_info, num_frames_to_detect_scenecut, /*search_start_idx=*/0); if (frames_to_key != -1) rc->frames_to_key = AOMMIN(rc->frames_to_key, frames_to_key); } } FIRSTPASS_STATS this_frame; av1_zero(this_frame); // call above fn if (is_stat_consumption_stage(cpi)) { if (cpi->gf_frame_index < gf_group->size || rc->frames_to_key == 0) { process_first_pass_stats(cpi, &this_frame); update_total_stats = 1; } } else { rc->active_worst_quality = oxcf->rc_cfg.cq_level; } // Keyframe and section processing. FIRSTPASS_STATS this_frame_copy; this_frame_copy = this_frame; if (rc->frames_to_key <= 0) { assert(rc->frames_to_key == 0); // Define next KF group and assign bits to it. frame_params->frame_type = KEY_FRAME; find_next_key_frame(cpi, &this_frame); this_frame = this_frame_copy; } if (rc->frames_to_fwd_kf <= 0) rc->frames_to_fwd_kf = oxcf->kf_cfg.fwd_kf_dist; // Define a new GF/ARF group. (Should always enter here for key frames). if (cpi->gf_frame_index == gf_group->size) { av1_tf_info_reset(&cpi->ppi->tf_info); #if CONFIG_BITRATE_ACCURACY && !CONFIG_THREE_PASS vbr_rc_reset_gop_data(&cpi->vbr_rc_info); #endif // CONFIG_BITRATE_ACCURACY int max_gop_length = (oxcf->gf_cfg.lag_in_frames >= 32) ? AOMMIN(MAX_GF_INTERVAL, oxcf->gf_cfg.lag_in_frames - oxcf->algo_cfg.arnr_max_frames / 2) : MAX_GF_LENGTH_LAP; // Handle forward key frame when enabled. if (oxcf->kf_cfg.fwd_kf_dist > 0) max_gop_length = AOMMIN(rc->frames_to_fwd_kf + 1, max_gop_length); // Use the provided gop size in low delay setting if (oxcf->gf_cfg.lag_in_frames == 0) max_gop_length = rc->max_gf_interval; // Limit the max gop length for the last gop in 1 pass setting. max_gop_length = AOMMIN(max_gop_length, rc->frames_to_key); // Identify regions if needed. // TODO(bohanli): identify regions for all stats available. if (rc->frames_since_key == 0 || rc->frames_since_key == 1 || (p_rc->frames_till_regions_update - rc->frames_since_key < rc->frames_to_key && p_rc->frames_till_regions_update - rc->frames_since_key < max_gop_length + 1)) { // how many frames we can analyze from this frame int rest_frames = AOMMIN(rc->frames_to_key, MAX_FIRSTPASS_ANALYSIS_FRAMES); rest_frames = AOMMIN(rest_frames, (int)(twopass->stats_buf_ctx->stats_in_end - cpi->twopass_frame.stats_in + (rc->frames_since_key == 0))); p_rc->frames_till_regions_update = rest_frames; int ret; if (cpi->ppi->lap_enabled) { av1_mark_flashes(twopass->stats_buf_ctx->stats_in_start, twopass->stats_buf_ctx->stats_in_end); av1_estimate_noise(twopass->stats_buf_ctx->stats_in_start, twopass->stats_buf_ctx->stats_in_end, cpi->common.error); av1_estimate_coeff(twopass->stats_buf_ctx->stats_in_start, twopass->stats_buf_ctx->stats_in_end); ret = identify_regions(cpi->twopass_frame.stats_in, rest_frames, (rc->frames_since_key == 0), p_rc->regions, &p_rc->num_regions); } else { ret = identify_regions( cpi->twopass_frame.stats_in - (rc->frames_since_key == 0), rest_frames, 0, p_rc->regions, &p_rc->num_regions); } if (ret == -1) { aom_internal_error(cpi->common.error, AOM_CODEC_MEM_ERROR, "Error allocating buffers in identify_regions"); } } int cur_region_idx = find_regions_index(p_rc->regions, p_rc->num_regions, rc->frames_since_key - p_rc->regions_offset); if ((cur_region_idx >= 0 && p_rc->regions[cur_region_idx].type == SCENECUT_REGION) || rc->frames_since_key == 0) { // If we start from a scenecut, then the last GOP's arf boost is not // needed for this GOP. cpi->ppi->gf_state.arf_gf_boost_lst = 0; } int need_gf_len = 1; if (cpi->third_pass_ctx && oxcf->pass == AOM_RC_THIRD_PASS) { // set up bitstream to read if (!cpi->third_pass_ctx->input_file_name && oxcf->two_pass_output) { cpi->third_pass_ctx->input_file_name = oxcf->two_pass_output; } av1_open_second_pass_log(cpi, 1); THIRD_PASS_GOP_INFO *gop_info = &cpi->third_pass_ctx->gop_info; // Read in GOP information from the second pass file. av1_read_second_pass_gop_info(cpi->second_pass_log_stream, gop_info, cpi->common.error); #if CONFIG_BITRATE_ACCURACY TPL_INFO *tpl_info; AOM_CHECK_MEM_ERROR(cpi->common.error, tpl_info, aom_malloc(sizeof(*tpl_info))); av1_read_tpl_info(tpl_info, cpi->second_pass_log_stream, cpi->common.error); aom_free(tpl_info); #if CONFIG_THREE_PASS // TODO(angiebird): Put this part into a func cpi->vbr_rc_info.cur_gop_idx++; #endif // CONFIG_THREE_PASS #endif // CONFIG_BITRATE_ACCURACY // Read in third_pass_info from the bitstream. av1_set_gop_third_pass(cpi->third_pass_ctx); // Read in per-frame info from second-pass encoding av1_read_second_pass_per_frame_info( cpi->second_pass_log_stream, cpi->third_pass_ctx->frame_info, gop_info->num_frames, cpi->common.error); p_rc->cur_gf_index = 0; p_rc->gf_intervals[0] = cpi->third_pass_ctx->gop_info.gf_length; need_gf_len = 0; } if (need_gf_len) { // If we cannot obtain GF group length from second_pass_file // TODO(jingning): Resolve the redundant calls here. if (rc->intervals_till_gf_calculate_due == 0 || 1) { calculate_gf_length(cpi, max_gop_length, MAX_NUM_GF_INTERVALS); } if (max_gop_length > 16 && oxcf->algo_cfg.enable_tpl_model && oxcf->gf_cfg.lag_in_frames >= 32 && cpi->sf.tpl_sf.gop_length_decision_method != 3) { int this_idx = rc->frames_since_key + p_rc->gf_intervals[p_rc->cur_gf_index] - p_rc->regions_offset - 1; int this_region = find_regions_index(p_rc->regions, p_rc->num_regions, this_idx); int next_region = find_regions_index(p_rc->regions, p_rc->num_regions, this_idx + 1); // TODO(angiebird): Figure out why this_region and next_region are -1 in // unit test like AltRefFramePresenceTestLarge (aomedia:3134) int is_last_scenecut = p_rc->gf_intervals[p_rc->cur_gf_index] >= rc->frames_to_key || (this_region != -1 && p_rc->regions[this_region].type == SCENECUT_REGION) || (next_region != -1 && p_rc->regions[next_region].type == SCENECUT_REGION); int ori_gf_int = p_rc->gf_intervals[p_rc->cur_gf_index]; if (p_rc->gf_intervals[p_rc->cur_gf_index] > 16 && rc->min_gf_interval <= 16) { // The calculate_gf_length function is previously used with // max_gop_length = 32 with look-ahead gf intervals. define_gf_group(cpi, frame_params, 0); av1_tf_info_filtering(&cpi->ppi->tf_info, cpi, gf_group); this_frame = this_frame_copy; if (is_shorter_gf_interval_better(cpi, frame_params)) { // A shorter gf interval is better. // TODO(jingning): Remove redundant computations here. max_gop_length = 16; calculate_gf_length(cpi, max_gop_length, 1); if (is_last_scenecut && (ori_gf_int - p_rc->gf_intervals[p_rc->cur_gf_index] < 4)) { p_rc->gf_intervals[p_rc->cur_gf_index] = ori_gf_int; } } } } } define_gf_group(cpi, frame_params, 0); if (gf_group->update_type[cpi->gf_frame_index] != ARF_UPDATE && rc->frames_since_key > 0) process_first_pass_stats(cpi, &this_frame); define_gf_group(cpi, frame_params, 1); // write gop info if needed for third pass. Per-frame info is written after // each frame is encoded. av1_write_second_pass_gop_info(cpi); av1_tf_info_filtering(&cpi->ppi->tf_info, cpi, gf_group); rc->frames_till_gf_update_due = p_rc->baseline_gf_interval; assert(cpi->gf_frame_index == 0); #if ARF_STATS_OUTPUT { FILE *fpfile; fpfile = fopen("arf.stt", "a"); ++arf_count; fprintf(fpfile, "%10d %10d %10d %10d %10d\n", cpi->common.current_frame.frame_number, rc->frames_till_gf_update_due, cpi->ppi->p_rc.kf_boost, arf_count, p_rc->gfu_boost); fclose(fpfile); } #endif } assert(cpi->gf_frame_index < gf_group->size); if (gf_group->update_type[cpi->gf_frame_index] == ARF_UPDATE || gf_group->update_type[cpi->gf_frame_index] == INTNL_ARF_UPDATE) { reset_fpf_position(&cpi->twopass_frame, start_pos); const FIRSTPASS_STATS *const this_frame_ptr = read_frame_stats(twopass, &cpi->twopass_frame, gf_group->arf_src_offset[cpi->gf_frame_index]); set_twopass_params_based_on_fp_stats(cpi, this_frame_ptr); } else { // Back up this frame's stats for updating total stats during post encode. cpi->twopass_frame.this_frame = update_total_stats ? start_pos : NULL; } frame_params->frame_type = gf_group->frame_type[cpi->gf_frame_index]; setup_target_rate(cpi); } void av1_init_second_pass(AV1_COMP *cpi) { const AV1EncoderConfig *const oxcf = &cpi->oxcf; TWO_PASS *const twopass = &cpi->ppi->twopass; FRAME_INFO *const frame_info = &cpi->frame_info; double frame_rate; FIRSTPASS_STATS *stats; if (!twopass->stats_buf_ctx->stats_in_end) return; av1_mark_flashes(twopass->stats_buf_ctx->stats_in_start, twopass->stats_buf_ctx->stats_in_end); av1_estimate_noise(twopass->stats_buf_ctx->stats_in_start, twopass->stats_buf_ctx->stats_in_end, cpi->common.error); av1_estimate_coeff(twopass->stats_buf_ctx->stats_in_start, twopass->stats_buf_ctx->stats_in_end); stats = twopass->stats_buf_ctx->total_stats; *stats = *twopass->stats_buf_ctx->stats_in_end; *twopass->stats_buf_ctx->total_left_stats = *stats; frame_rate = 10000000.0 * stats->count / stats->duration; // Each frame can have a different duration, as the frame rate in the source // isn't guaranteed to be constant. The frame rate prior to the first frame // encoded in the second pass is a guess. However, the sum duration is not. // It is calculated based on the actual durations of all frames from the // first pass. av1_new_framerate(cpi, frame_rate); twopass->bits_left = (int64_t)(stats->duration * oxcf->rc_cfg.target_bandwidth / 10000000.0); #if CONFIG_BITRATE_ACCURACY av1_vbr_rc_init(&cpi->vbr_rc_info, twopass->bits_left, (int)round(stats->count)); #endif #if CONFIG_RATECTRL_LOG rc_log_init(&cpi->rc_log); #endif // This variable monitors how far behind the second ref update is lagging. twopass->sr_update_lag = 1; // Scan the first pass file and calculate a modified total error based upon // the bias/power function used to allocate bits. { const double avg_error = stats->coded_error / DOUBLE_DIVIDE_CHECK(stats->count); const FIRSTPASS_STATS *s = cpi->twopass_frame.stats_in; double modified_error_total = 0.0; twopass->modified_error_min = (avg_error * oxcf->rc_cfg.vbrmin_section) / 100; twopass->modified_error_max = (avg_error * oxcf->rc_cfg.vbrmax_section) / 100; while (s < twopass->stats_buf_ctx->stats_in_end) { modified_error_total += calculate_modified_err(frame_info, twopass, oxcf, s); ++s; } twopass->modified_error_left = modified_error_total; } // Reset the vbr bits off target counters cpi->ppi->p_rc.vbr_bits_off_target = 0; cpi->ppi->p_rc.vbr_bits_off_target_fast = 0; cpi->ppi->p_rc.rate_error_estimate = 0; // Static sequence monitor variables. twopass->kf_zeromotion_pct = 100; twopass->last_kfgroup_zeromotion_pct = 100; // Initialize bits per macro_block estimate correction factor. twopass->bpm_factor = 1.0; // Initialize actual and target bits counters for ARF groups so that // at the start we have a neutral bpm adjustment. twopass->rolling_arf_group_target_bits = 1; twopass->rolling_arf_group_actual_bits = 1; } void av1_init_single_pass_lap(AV1_COMP *cpi) { TWO_PASS *const twopass = &cpi->ppi->twopass; if (!twopass->stats_buf_ctx->stats_in_end) return; // This variable monitors how far behind the second ref update is lagging. twopass->sr_update_lag = 1; twopass->bits_left = 0; twopass->modified_error_min = 0.0; twopass->modified_error_max = 0.0; twopass->modified_error_left = 0.0; // Reset the vbr bits off target counters cpi->ppi->p_rc.vbr_bits_off_target = 0; cpi->ppi->p_rc.vbr_bits_off_target_fast = 0; cpi->ppi->p_rc.rate_error_estimate = 0; // Static sequence monitor variables. twopass->kf_zeromotion_pct = 100; twopass->last_kfgroup_zeromotion_pct = 100; // Initialize bits per macro_block estimate correction factor. twopass->bpm_factor = 1.0; // Initialize actual and target bits counters for ARF groups so that // at the start we have a neutral bpm adjustment. twopass->rolling_arf_group_target_bits = 1; twopass->rolling_arf_group_actual_bits = 1; } #define MINQ_ADJ_LIMIT 48 #define MINQ_ADJ_LIMIT_CQ 20 #define HIGH_UNDERSHOOT_RATIO 2 void av1_twopass_postencode_update(AV1_COMP *cpi) { TWO_PASS *const twopass = &cpi->ppi->twopass; RATE_CONTROL *const rc = &cpi->rc; PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc; const RateControlCfg *const rc_cfg = &cpi->oxcf.rc_cfg; // Increment the stats_in pointer. if (is_stat_consumption_stage(cpi) && !(cpi->use_ducky_encode && cpi->ducky_encode_info.frame_info.gop_mode == DUCKY_ENCODE_GOP_MODE_RCL) && (cpi->gf_frame_index < cpi->ppi->gf_group.size || rc->frames_to_key == 0)) { const int update_type = cpi->ppi->gf_group.update_type[cpi->gf_frame_index]; if (update_type != ARF_UPDATE && update_type != INTNL_ARF_UPDATE) { FIRSTPASS_STATS this_frame; assert(cpi->twopass_frame.stats_in > twopass->stats_buf_ctx->stats_in_start); --cpi->twopass_frame.stats_in; if (cpi->ppi->lap_enabled) { input_stats_lap(twopass, &cpi->twopass_frame, &this_frame); } else { input_stats(twopass, &cpi->twopass_frame, &this_frame); } } else if (cpi->ppi->lap_enabled) { cpi->twopass_frame.stats_in = twopass->stats_buf_ctx->stats_in_start; } } // VBR correction is done through rc->vbr_bits_off_target. Based on the // sign of this value, a limited % adjustment is made to the target rate // of subsequent frames, to try and push it back towards 0. This method // is designed to prevent extreme behaviour at the end of a clip // or group of frames. p_rc->vbr_bits_off_target += rc->base_frame_target - rc->projected_frame_size; twopass->bits_left = AOMMAX(twopass->bits_left - rc->base_frame_target, 0); if (cpi->do_update_vbr_bits_off_target_fast) { // Subtract current frame's fast_extra_bits. p_rc->vbr_bits_off_target_fast -= rc->frame_level_fast_extra_bits; rc->frame_level_fast_extra_bits = 0; } // Target vs actual bits for this arf group. twopass->rolling_arf_group_target_bits += rc->base_frame_target; twopass->rolling_arf_group_actual_bits += rc->projected_frame_size; // Calculate the pct rc error. if (p_rc->total_actual_bits) { p_rc->rate_error_estimate = (int)((p_rc->vbr_bits_off_target * 100) / p_rc->total_actual_bits); p_rc->rate_error_estimate = clamp(p_rc->rate_error_estimate, -100, 100); } else { p_rc->rate_error_estimate = 0; } #if CONFIG_FPMT_TEST /* The variables temp_vbr_bits_off_target, temp_bits_left, * temp_rolling_arf_group_target_bits, temp_rolling_arf_group_actual_bits * temp_rate_error_estimate are introduced for quality simulation purpose, * it retains the value previous to the parallel encode frames. The * variables are updated based on the update flag. * * If there exist show_existing_frames between parallel frames, then to * retain the temp state do not update it. */ const int simulate_parallel_frame = cpi->ppi->fpmt_unit_test_cfg == PARALLEL_SIMULATION_ENCODE; int show_existing_between_parallel_frames = (cpi->ppi->gf_group.update_type[cpi->gf_frame_index] == INTNL_OVERLAY_UPDATE && cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index + 1] == 2); if (cpi->do_frame_data_update && !show_existing_between_parallel_frames && simulate_parallel_frame) { cpi->ppi->p_rc.temp_vbr_bits_off_target = p_rc->vbr_bits_off_target; cpi->ppi->p_rc.temp_bits_left = twopass->bits_left; cpi->ppi->p_rc.temp_rolling_arf_group_target_bits = twopass->rolling_arf_group_target_bits; cpi->ppi->p_rc.temp_rolling_arf_group_actual_bits = twopass->rolling_arf_group_actual_bits; cpi->ppi->p_rc.temp_rate_error_estimate = p_rc->rate_error_estimate; } #endif // Update the active best quality pyramid. if (!rc->is_src_frame_alt_ref) { const int pyramid_level = cpi->ppi->gf_group.layer_depth[cpi->gf_frame_index]; int i; for (i = pyramid_level; i <= MAX_ARF_LAYERS; ++i) { p_rc->active_best_quality[i] = cpi->common.quant_params.base_qindex; #if CONFIG_TUNE_VMAF if (cpi->vmaf_info.original_qindex != -1 && (cpi->oxcf.tune_cfg.tuning >= AOM_TUNE_VMAF_WITH_PREPROCESSING && cpi->oxcf.tune_cfg.tuning <= AOM_TUNE_VMAF_NEG_MAX_GAIN)) { p_rc->active_best_quality[i] = cpi->vmaf_info.original_qindex; } #endif } } #if 0 { AV1_COMMON *cm = &cpi->common; FILE *fpfile; fpfile = fopen("details.stt", "a"); fprintf(fpfile, "%10d %10d %10d %10" PRId64 " %10" PRId64 " %10d %10d %10d %10.4lf %10.4lf %10.4lf %10.4lf\n", cm->current_frame.frame_number, rc->base_frame_target, rc->projected_frame_size, rc->total_actual_bits, rc->vbr_bits_off_target, p_rc->rate_error_estimate, twopass->rolling_arf_group_target_bits, twopass->rolling_arf_group_actual_bits, (double)twopass->rolling_arf_group_actual_bits / (double)twopass->rolling_arf_group_target_bits, twopass->bpm_factor, av1_convert_qindex_to_q(cpi->common.quant_params.base_qindex, cm->seq_params->bit_depth), av1_convert_qindex_to_q(rc->active_worst_quality, cm->seq_params->bit_depth)); fclose(fpfile); } #endif if (cpi->common.current_frame.frame_type != KEY_FRAME) { twopass->kf_group_bits -= rc->base_frame_target; twopass->last_kfgroup_zeromotion_pct = twopass->kf_zeromotion_pct; } twopass->kf_group_bits = AOMMAX(twopass->kf_group_bits, 0); // If the rate control is drifting consider adjustment to min or maxq. if ((rc_cfg->mode != AOM_Q) && !cpi->rc.is_src_frame_alt_ref && (p_rc->rolling_target_bits > 0)) { int minq_adj_limit; int maxq_adj_limit; minq_adj_limit = (rc_cfg->mode == AOM_CQ ? MINQ_ADJ_LIMIT_CQ : MINQ_ADJ_LIMIT); maxq_adj_limit = (rc->worst_quality - rc->active_worst_quality); // Undershoot if ((rc_cfg->under_shoot_pct < 100) && (p_rc->rolling_actual_bits < p_rc->rolling_target_bits)) { int pct_error = ((p_rc->rolling_target_bits - p_rc->rolling_actual_bits) * 100) / p_rc->rolling_target_bits; if ((pct_error >= rc_cfg->under_shoot_pct) && (p_rc->rate_error_estimate > 0)) { twopass->extend_minq += 1; twopass->extend_maxq -= 1; } // Overshoot } else if ((rc_cfg->over_shoot_pct < 100) && (p_rc->rolling_actual_bits > p_rc->rolling_target_bits)) { int pct_error = ((p_rc->rolling_actual_bits - p_rc->rolling_target_bits) * 100) / p_rc->rolling_target_bits; pct_error = clamp(pct_error, 0, 100); if ((pct_error >= rc_cfg->over_shoot_pct) && (p_rc->rate_error_estimate < 0)) { twopass->extend_maxq += 1; twopass->extend_minq -= 1; } } twopass->extend_minq = clamp(twopass->extend_minq, -minq_adj_limit, minq_adj_limit); twopass->extend_maxq = clamp(twopass->extend_maxq, 0, maxq_adj_limit); // If there is a big and undexpected undershoot then feed the extra // bits back in quickly. One situation where this may happen is if a // frame is unexpectedly almost perfectly predicted by the ARF or GF // but not very well predcited by the previous frame. if (!frame_is_kf_gf_arf(cpi) && !cpi->rc.is_src_frame_alt_ref) { int fast_extra_thresh = rc->base_frame_target / HIGH_UNDERSHOOT_RATIO; if (rc->projected_frame_size < fast_extra_thresh) { p_rc->vbr_bits_off_target_fast += fast_extra_thresh - rc->projected_frame_size; p_rc->vbr_bits_off_target_fast = AOMMIN(p_rc->vbr_bits_off_target_fast, (4 * rc->avg_frame_bandwidth)); } } #if CONFIG_FPMT_TEST if (cpi->do_frame_data_update && !show_existing_between_parallel_frames && simulate_parallel_frame) { cpi->ppi->p_rc.temp_vbr_bits_off_target_fast = p_rc->vbr_bits_off_target_fast; cpi->ppi->p_rc.temp_extend_minq = twopass->extend_minq; cpi->ppi->p_rc.temp_extend_maxq = twopass->extend_maxq; } #endif } // Update the frame probabilities obtained from parallel encode frames FrameProbInfo *const frame_probs = &cpi->ppi->frame_probs; #if CONFIG_FPMT_TEST /* The variable temp_active_best_quality is introduced only for quality * simulation purpose, it retains the value previous to the parallel * encode frames. The variable is updated based on the update flag. * * If there exist show_existing_frames between parallel frames, then to * retain the temp state do not update it. */ if (cpi->do_frame_data_update && !show_existing_between_parallel_frames && simulate_parallel_frame) { int i; const int pyramid_level = cpi->ppi->gf_group.layer_depth[cpi->gf_frame_index]; if (!rc->is_src_frame_alt_ref) { for (i = pyramid_level; i <= MAX_ARF_LAYERS; ++i) cpi->ppi->p_rc.temp_active_best_quality[i] = p_rc->active_best_quality[i]; } } // Update the frame probabilities obtained from parallel encode frames FrameProbInfo *const temp_frame_probs_simulation = simulate_parallel_frame ? &cpi->ppi->temp_frame_probs_simulation : frame_probs; FrameProbInfo *const temp_frame_probs = simulate_parallel_frame ? &cpi->ppi->temp_frame_probs : NULL; #endif int i, j, loop; // Sequentially do average on temp_frame_probs_simulation which holds // probabilities of last frame before parallel encode for (loop = 0; loop <= cpi->num_frame_recode; loop++) { // Sequentially update tx_type_probs if (cpi->do_update_frame_probs_txtype[loop] && (cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0)) { const FRAME_UPDATE_TYPE update_type = get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index); for (i = 0; i < TX_SIZES_ALL; i++) { int left = 1024; for (j = TX_TYPES - 1; j >= 0; j--) { const int new_prob = cpi->frame_new_probs[loop].tx_type_probs[update_type][i][j]; #if CONFIG_FPMT_TEST int prob = (temp_frame_probs_simulation->tx_type_probs[update_type][i][j] + new_prob) >> 1; left -= prob; if (j == 0) prob += left; temp_frame_probs_simulation->tx_type_probs[update_type][i][j] = prob; #else int prob = (frame_probs->tx_type_probs[update_type][i][j] + new_prob) >> 1; left -= prob; if (j == 0) prob += left; frame_probs->tx_type_probs[update_type][i][j] = prob; #endif } } } // Sequentially update obmc_probs if (cpi->do_update_frame_probs_obmc[loop] && cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0) { const FRAME_UPDATE_TYPE update_type = get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index); for (i = 0; i < BLOCK_SIZES_ALL; i++) { const int new_prob = cpi->frame_new_probs[loop].obmc_probs[update_type][i]; #if CONFIG_FPMT_TEST temp_frame_probs_simulation->obmc_probs[update_type][i] = (temp_frame_probs_simulation->obmc_probs[update_type][i] + new_prob) >> 1; #else frame_probs->obmc_probs[update_type][i] = (frame_probs->obmc_probs[update_type][i] + new_prob) >> 1; #endif } } // Sequentially update warped_probs if (cpi->do_update_frame_probs_warp[loop] && cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0) { const FRAME_UPDATE_TYPE update_type = get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index); const int new_prob = cpi->frame_new_probs[loop].warped_probs[update_type]; #if CONFIG_FPMT_TEST temp_frame_probs_simulation->warped_probs[update_type] = (temp_frame_probs_simulation->warped_probs[update_type] + new_prob) >> 1; #else frame_probs->warped_probs[update_type] = (frame_probs->warped_probs[update_type] + new_prob) >> 1; #endif } // Sequentially update switchable_interp_probs if (cpi->do_update_frame_probs_interpfilter[loop] && cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0) { const FRAME_UPDATE_TYPE update_type = get_frame_update_type(&cpi->ppi->gf_group, cpi->gf_frame_index); for (i = 0; i < SWITCHABLE_FILTER_CONTEXTS; i++) { int left = 1536; for (j = SWITCHABLE_FILTERS - 1; j >= 0; j--) { const int new_prob = cpi->frame_new_probs[loop] .switchable_interp_probs[update_type][i][j]; #if CONFIG_FPMT_TEST int prob = (temp_frame_probs_simulation ->switchable_interp_probs[update_type][i][j] + new_prob) >> 1; left -= prob; if (j == 0) prob += left; temp_frame_probs_simulation ->switchable_interp_probs[update_type][i][j] = prob; #else int prob = (frame_probs->switchable_interp_probs[update_type][i][j] + new_prob) >> 1; left -= prob; if (j == 0) prob += left; frame_probs->switchable_interp_probs[update_type][i][j] = prob; #endif } } } } #if CONFIG_FPMT_TEST // Copying temp_frame_probs_simulation to temp_frame_probs based on // the flag if (cpi->do_frame_data_update && cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0 && simulate_parallel_frame) { for (int update_type_idx = 0; update_type_idx < FRAME_UPDATE_TYPES; update_type_idx++) { for (i = 0; i < BLOCK_SIZES_ALL; i++) { temp_frame_probs->obmc_probs[update_type_idx][i] = temp_frame_probs_simulation->obmc_probs[update_type_idx][i]; } temp_frame_probs->warped_probs[update_type_idx] = temp_frame_probs_simulation->warped_probs[update_type_idx]; for (i = 0; i < TX_SIZES_ALL; i++) { for (j = 0; j < TX_TYPES; j++) { temp_frame_probs->tx_type_probs[update_type_idx][i][j] = temp_frame_probs_simulation->tx_type_probs[update_type_idx][i][j]; } } for (i = 0; i < SWITCHABLE_FILTER_CONTEXTS; i++) { for (j = 0; j < SWITCHABLE_FILTERS; j++) { temp_frame_probs->switchable_interp_probs[update_type_idx][i][j] = temp_frame_probs_simulation ->switchable_interp_probs[update_type_idx][i][j]; } } } } #endif // Update framerate obtained from parallel encode frames if (cpi->common.show_frame && cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index] > 0) cpi->framerate = cpi->new_framerate; #if CONFIG_FPMT_TEST // SIMULATION PURPOSE int show_existing_between_parallel_frames_cndn = (cpi->ppi->gf_group.update_type[cpi->gf_frame_index] == INTNL_OVERLAY_UPDATE && cpi->ppi->gf_group.frame_parallel_level[cpi->gf_frame_index + 1] == 2); if (cpi->common.show_frame && !show_existing_between_parallel_frames_cndn && cpi->do_frame_data_update && simulate_parallel_frame) cpi->temp_framerate = cpi->framerate; #endif }