Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1687 insertions, 0 deletions

diff --git a/media/ffvpx/libavcodec/decode.c b/media/ffvpx/libavcodec/decode.c
new file mode 100644
index 0000000000..be2be81089
--- /dev/null
+++ b/media/ffvpx/libavcodec/decode.c
@@ -0,0 +1,1687 @@
+/*
+ * generic decoding-related code
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include <string.h>
+
+#include "config.h"
+
+#if CONFIG_ICONV
+# include <iconv.h>
+#endif
+
+#include "libavutil/avassert.h"
+#include "libavutil/avstring.h"
+#include "libavutil/bprint.h"
+#include "libavutil/channel_layout.h"
+#include "libavutil/common.h"
+#include "libavutil/fifo.h"
+#include "libavutil/frame.h"
+#include "libavutil/hwcontext.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/internal.h"
+#include "libavutil/intmath.h"
+#include "libavutil/opt.h"
+
+#include "avcodec.h"
+#include "bytestream.h"
+#include "bsf.h"
+#include "codec_internal.h"
+#include "decode.h"
+#include "hwconfig.h"
+#include "internal.h"
+#include "thread.h"
+
+static int apply_param_change(AVCodecContext *avctx, const AVPacket *avpkt)
+{
+    int ret;
+    size_t size;
+    const uint8_t *data;
+    uint32_t flags;
+    int64_t val;
+
+    data = av_packet_get_side_data(avpkt, AV_PKT_DATA_PARAM_CHANGE, &size);
+    if (!data)
+        return 0;
+
+    if (!(avctx->codec->capabilities & AV_CODEC_CAP_PARAM_CHANGE)) {
+        av_log(avctx, AV_LOG_ERROR, "This decoder does not support parameter "
+               "changes, but PARAM_CHANGE side data was sent to it.\n");
+        ret = AVERROR(EINVAL);
+        goto fail2;
+    }
+
+    if (size < 4)
+        goto fail;
+
+    flags = bytestream_get_le32(&data);
+    size -= 4;
+
+#if FF_API_OLD_CHANNEL_LAYOUT
+FF_DISABLE_DEPRECATION_WARNINGS
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT) {
+        if (size < 4)
+            goto fail;
+        val = bytestream_get_le32(&data);
+        if (val <= 0 || val > INT_MAX) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid channel count");
+            ret = AVERROR_INVALIDDATA;
+            goto fail2;
+        }
+        avctx->channels = val;
+        size -= 4;
+    }
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT) {
+        if (size < 8)
+            goto fail;
+        avctx->channel_layout = bytestream_get_le64(&data);
+        size -= 8;
+    }
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE) {
+        if (size < 4)
+            goto fail;
+        val = bytestream_get_le32(&data);
+        if (val <= 0 || val > INT_MAX) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid sample rate");
+            ret = AVERROR_INVALIDDATA;
+            goto fail2;
+        }
+        avctx->sample_rate = val;
+        size -= 4;
+    }
+    if (flags & AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS) {
+        if (size < 8)
+            goto fail;
+        avctx->width  = bytestream_get_le32(&data);
+        avctx->height = bytestream_get_le32(&data);
+        size -= 8;
+        ret = ff_set_dimensions(avctx, avctx->width, avctx->height);
+        if (ret < 0)
+            goto fail2;
+    }
+
+    return 0;
+fail:
+    av_log(avctx, AV_LOG_ERROR, "PARAM_CHANGE side data too small.\n");
+    ret = AVERROR_INVALIDDATA;
+fail2:
+    if (ret < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Error applying parameter changes.\n");
+        if (avctx->err_recognition & AV_EF_EXPLODE)
+            return ret;
+    }
+    return 0;
+}
+
+static int extract_packet_props(AVCodecInternal *avci, const AVPacket *pkt)
+{
+    int ret = 0;
+
+    av_packet_unref(avci->last_pkt_props);
+    if (pkt) {
+        ret = av_packet_copy_props(avci->last_pkt_props, pkt);
+        if (!ret)
+            avci->last_pkt_props->opaque = (void *)(intptr_t)pkt->size; // Needed for ff_decode_frame_props().
+    }
+    return ret;
+}
+
+static int decode_bsfs_init(AVCodecContext *avctx)
+{
+    AVCodecInternal *avci = avctx->internal;
+    const FFCodec *const codec = ffcodec(avctx->codec);
+    int ret;
+
+    if (avci->bsf)
+        return 0;
+
+    ret = av_bsf_list_parse_str(codec->bsfs, &avci->bsf);
+    if (ret < 0) {
+        av_log(avctx, AV_LOG_ERROR, "Error parsing decoder bitstream filters '%s': %s\n", codec->bsfs, av_err2str(ret));
+        if (ret != AVERROR(ENOMEM))
+            ret = AVERROR_BUG;
+        goto fail;
+    }
+
+    /* We do not currently have an API for passing the input timebase into decoders,
+     * but no filters used here should actually need it.
+     * So we make up some plausible-looking number (the MPEG 90kHz timebase) */
+    avci->bsf->time_base_in = (AVRational){ 1, 90000 };
+    ret = avcodec_parameters_from_context(avci->bsf->par_in, avctx);
+    if (ret < 0)
+        goto fail;
+
+    ret = av_bsf_init(avci->bsf);
+    if (ret < 0)
+        goto fail;
+
+    return 0;
+fail:
+    av_bsf_free(&avci->bsf);
+    return ret;
+}
+
+int ff_decode_get_packet(AVCodecContext *avctx, AVPacket *pkt)
+{
+    AVCodecInternal *avci = avctx->internal;
+    int ret;
+
+    if (avci->draining)
+        return AVERROR_EOF;
+
+    ret = av_bsf_receive_packet(avci->bsf, pkt);
+    if (ret == AVERROR_EOF)
+        avci->draining = 1;
+    if (ret < 0)
+        return ret;
+
+    if (!(ffcodec(avctx->codec)->caps_internal & FF_CODEC_CAP_SETS_FRAME_PROPS)) {
+        ret = extract_packet_props(avctx->internal, pkt);
+        if (ret < 0)
+            goto finish;
+    }
+
+    ret = apply_param_change(avctx, pkt);
+    if (ret < 0)
+        goto finish;
+
+    return 0;
+finish:
+    av_packet_unref(pkt);
+    return ret;
+}
+
+/**
+ * Attempt to guess proper monotonic timestamps for decoded video frames
+ * which might have incorrect times. Input timestamps may wrap around, in
+ * which case the output will as well.
+ *
+ * @param pts the pts field of the decoded AVPacket, as passed through
+ * AVFrame.pts
+ * @param dts the dts field of the decoded AVPacket
+ * @return one of the input values, may be AV_NOPTS_VALUE
+ */
+static int64_t guess_correct_pts(AVCodecContext *ctx,
+                                 int64_t reordered_pts, int64_t dts)
+{
+    int64_t pts = AV_NOPTS_VALUE;
+
+    if (dts != AV_NOPTS_VALUE) {
+        ctx->pts_correction_num_faulty_dts += dts <= ctx->pts_correction_last_dts;
+        ctx->pts_correction_last_dts = dts;
+    } else if (reordered_pts != AV_NOPTS_VALUE)
+        ctx->pts_correction_last_dts = reordered_pts;
+
+    if (reordered_pts != AV_NOPTS_VALUE) {
+        ctx->pts_correction_num_faulty_pts += reordered_pts <= ctx->pts_correction_last_pts;
+        ctx->pts_correction_last_pts = reordered_pts;
+    } else if(dts != AV_NOPTS_VALUE)
+        ctx->pts_correction_last_pts = dts;
+
+    if ((ctx->pts_correction_num_faulty_pts<=ctx->pts_correction_num_faulty_dts || dts == AV_NOPTS_VALUE)
+       && reordered_pts != AV_NOPTS_VALUE)
+        pts = reordered_pts;
+    else
+        pts = dts;
+
+    return pts;
+}
+
+/*
+ * The core of the receive_frame_wrapper for the decoders implementing
+ * the simple API. Certain decoders might consume partial packets without
+ * returning any output, so this function needs to be called in a loop until it
+ * returns EAGAIN.
+ **/
+static inline int decode_simple_internal(AVCodecContext *avctx, AVFrame *frame, int64_t *discarded_samples)
+{
+    AVCodecInternal   *avci = avctx->internal;
+    AVPacket     *const pkt = avci->in_pkt;
+    const FFCodec *const codec = ffcodec(avctx->codec);
+    int got_frame, actual_got_frame;
+    int ret;
+
+    if (!pkt->data && !avci->draining) {
+        av_packet_unref(pkt);
+        ret = ff_decode_get_packet(avctx, pkt);
+        if (ret < 0 && ret != AVERROR_EOF)
+            return ret;
+    }
+
+    // Some codecs (at least wma lossless) will crash when feeding drain packets
+    // after EOF was signaled.
+    if (avci->draining_done)
+        return AVERROR_EOF;
+
+    if (!pkt->data &&
+        !(avctx->codec->capabilities & AV_CODEC_CAP_DELAY ||
+          avctx->active_thread_type & FF_THREAD_FRAME))
+        return AVERROR_EOF;
+
+    got_frame = 0;
+
+    if (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME) {
+        ret = ff_thread_decode_frame(avctx, frame, &got_frame, pkt);
+    } else {
+        ret = codec->cb.decode(avctx, frame, &got_frame, pkt);
+
+        if (!(codec->caps_internal & FF_CODEC_CAP_SETS_PKT_DTS))
+            frame->pkt_dts = pkt->dts;
+        if (avctx->codec->type == AVMEDIA_TYPE_VIDEO) {
+            if(!avctx->has_b_frames)
+                frame->pkt_pos = pkt->pos;
+            //FIXME these should be under if(!avctx->has_b_frames)
+            /* get_buffer is supposed to set frame parameters */
+            if (!(avctx->codec->capabilities & AV_CODEC_CAP_DR1)) {
+                if (!frame->sample_aspect_ratio.num)  frame->sample_aspect_ratio = avctx->sample_aspect_ratio;
+                if (!frame->width)                    frame->width               = avctx->width;
+                if (!frame->height)                   frame->height              = avctx->height;
+                if (frame->format == AV_PIX_FMT_NONE) frame->format              = avctx->pix_fmt;
+            }
+        }
+    }
+    emms_c();
+    actual_got_frame = got_frame;
+
+    if (avctx->codec->type == AVMEDIA_TYPE_VIDEO) {
+        if (frame->flags & AV_FRAME_FLAG_DISCARD)
+            got_frame = 0;
+    } else if (avctx->codec->type == AVMEDIA_TYPE_AUDIO) {
+        uint8_t *side;
+        size_t side_size;
+        uint32_t discard_padding = 0;
+        uint8_t skip_reason = 0;
+        uint8_t discard_reason = 0;
+
+        if (ret >= 0 && got_frame) {
+            if (frame->format == AV_SAMPLE_FMT_NONE)
+                frame->format = avctx->sample_fmt;
+            if (!frame->ch_layout.nb_channels) {
+                int ret2 = av_channel_layout_copy(&frame->ch_layout, &avctx->ch_layout);
+                if (ret2 < 0) {
+                    ret = ret2;
+                    got_frame = 0;
+                }
+            }
+#if FF_API_OLD_CHANNEL_LAYOUT
+FF_DISABLE_DEPRECATION_WARNINGS
+            if (!frame->channel_layout)
+                frame->channel_layout = avctx->ch_layout.order == AV_CHANNEL_ORDER_NATIVE ?
+                                        avctx->ch_layout.u.mask : 0;
+            if (!frame->channels)
+                frame->channels = avctx->ch_layout.nb_channels;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+            if (!frame->sample_rate)
+                frame->sample_rate = avctx->sample_rate;
+        }
+
+        side= av_packet_get_side_data(avci->last_pkt_props, AV_PKT_DATA_SKIP_SAMPLES, &side_size);
+        if(side && side_size>=10) {
+            avci->skip_samples = AV_RL32(side);
+            avci->skip_samples = FFMAX(0, avci->skip_samples);
+            discard_padding = AV_RL32(side + 4);
+            av_log(avctx, AV_LOG_DEBUG, "skip %d / discard %d samples due to side data\n",
+                   avci->skip_samples, (int)discard_padding);
+            skip_reason = AV_RL8(side + 8);
+            discard_reason = AV_RL8(side + 9);
+        }
+
+        if ((frame->flags & AV_FRAME_FLAG_DISCARD) && got_frame &&
+            !(avctx->flags2 & AV_CODEC_FLAG2_SKIP_MANUAL)) {
+            avci->skip_samples = FFMAX(0, avci->skip_samples - frame->nb_samples);
+            got_frame = 0;
+            *discarded_samples += frame->nb_samples;
+        }
+
+        if (avci->skip_samples > 0 && got_frame &&
+            !(avctx->flags2 & AV_CODEC_FLAG2_SKIP_MANUAL)) {
+            if(frame->nb_samples <= avci->skip_samples){
+                got_frame = 0;
+                *discarded_samples += frame->nb_samples;
+                avci->skip_samples -= frame->nb_samples;
+                av_log(avctx, AV_LOG_DEBUG, "skip whole frame, skip left: %d\n",
+                       avci->skip_samples);
+            } else {
+                av_samples_copy(frame->extended_data, frame->extended_data, 0, avci->skip_samples,
+                                frame->nb_samples - avci->skip_samples, avctx->ch_layout.nb_channels, frame->format);
+                if(avctx->pkt_timebase.num && avctx->sample_rate) {
+                    int64_t diff_ts = av_rescale_q(avci->skip_samples,
+                                                   (AVRational){1, avctx->sample_rate},
+                                                   avctx->pkt_timebase);
+                    if(frame->pts!=AV_NOPTS_VALUE)
+                        frame->pts += diff_ts;
+                    if(frame->pkt_dts!=AV_NOPTS_VALUE)
+                        frame->pkt_dts += diff_ts;
+                    if (frame->duration >= diff_ts)
+                        frame->duration -= diff_ts;
+                } else {
+                    av_log(avctx, AV_LOG_WARNING, "Could not update timestamps for skipped samples.\n");
+                }
+                av_log(avctx, AV_LOG_DEBUG, "skip %d/%d samples\n",
+                       avci->skip_samples, frame->nb_samples);
+                *discarded_samples += avci->skip_samples;
+                frame->nb_samples -= avci->skip_samples;
+                avci->skip_samples = 0;
+            }
+        }
+
+        if (discard_padding > 0 && discard_padding <= frame->nb_samples && got_frame &&
+            !(avctx->flags2 & AV_CODEC_FLAG2_SKIP_MANUAL)) {
+            if (discard_padding == frame->nb_samples) {
+                *discarded_samples += frame->nb_samples;
+                got_frame = 0;
+            } else {
+                if(avctx->pkt_timebase.num && avctx->sample_rate) {
+                    int64_t diff_ts = av_rescale_q(frame->nb_samples - discard_padding,
+                                                   (AVRational){1, avctx->sample_rate},
+                                                   avctx->pkt_timebase);
+                    frame->duration = diff_ts;
+                } else {
+                    av_log(avctx, AV_LOG_WARNING, "Could not update timestamps for discarded samples.\n");
+                }
+                av_log(avctx, AV_LOG_DEBUG, "discard %d/%d samples\n",
+                       (int)discard_padding, frame->nb_samples);
+                frame->nb_samples -= discard_padding;
+            }
+        }
+
+        if ((avctx->flags2 & AV_CODEC_FLAG2_SKIP_MANUAL) && got_frame) {
+            AVFrameSideData *fside = av_frame_new_side_data(frame, AV_FRAME_DATA_SKIP_SAMPLES, 10);
+            if (fside) {
+                AV_WL32(fside->data, avci->skip_samples);
+                AV_WL32(fside->data + 4, discard_padding);
+                AV_WL8(fside->data + 8, skip_reason);
+                AV_WL8(fside->data + 9, discard_reason);
+                avci->skip_samples = 0;
+            }
+        }
+    }
+
+    if (avctx->codec->type == AVMEDIA_TYPE_AUDIO &&
+        !avci->showed_multi_packet_warning &&
+        ret >= 0 && ret != pkt->size && !(avctx->codec->capabilities & AV_CODEC_CAP_SUBFRAMES)) {
+        av_log(avctx, AV_LOG_WARNING, "Multiple frames in a packet.\n");
+        avci->showed_multi_packet_warning = 1;
+    }
+
+    if (!got_frame)
+        av_frame_unref(frame);
+
+    if (ret >= 0 && avctx->codec->type == AVMEDIA_TYPE_VIDEO)
+        ret = pkt->size;
+
+    /* do not stop draining when actual_got_frame != 0 or ret < 0 */
+    /* got_frame == 0 but actual_got_frame != 0 when frame is discarded */
+    if (avci->draining && !actual_got_frame) {
+        if (ret < 0) {
+            /* prevent infinite loop if a decoder wrongly always return error on draining */
+            /* reasonable nb_errors_max = maximum b frames + thread count */
+            int nb_errors_max = 20 + (HAVE_THREADS && avctx->active_thread_type & FF_THREAD_FRAME ?
+                                avctx->thread_count : 1);
+
+            if (avci->nb_draining_errors++ >= nb_errors_max) {
+                av_log(avctx, AV_LOG_ERROR, "Too many errors when draining, this is a bug. "
+                       "Stop draining and force EOF.\n");
+                avci->draining_done = 1;
+                ret = AVERROR_BUG;
+            }
+        } else {
+            avci->draining_done = 1;
+        }
+    }
+
+    if (ret >= pkt->size || ret < 0) {
+        av_packet_unref(pkt);
+    } else {
+        int consumed = ret;
+
+        pkt->data                += consumed;
+        pkt->size                -= consumed;
+        pkt->pts                  = AV_NOPTS_VALUE;
+        pkt->dts                  = AV_NOPTS_VALUE;
+        if (!(codec->caps_internal & FF_CODEC_CAP_SETS_FRAME_PROPS)) {
+            // See extract_packet_props() comment.
+            avci->last_pkt_props->opaque = (void *)((intptr_t)avci->last_pkt_props->opaque - consumed);
+            avci->last_pkt_props->pts = AV_NOPTS_VALUE;
+            avci->last_pkt_props->dts = AV_NOPTS_VALUE;
+        }
+    }
+
+    if (got_frame)
+        av_assert0(frame->buf[0]);
+
+    return ret < 0 ? ret : 0;
+}
+
+#if CONFIG_LCMS2
+static int detect_colorspace(AVCodecContext *avctx, AVFrame *frame)
+{
+    AVCodecInternal *avci = avctx->internal;
+    enum AVColorTransferCharacteristic trc;
+    AVColorPrimariesDesc coeffs;
+    enum AVColorPrimaries prim;
+    cmsHPROFILE profile;
+    AVFrameSideData *sd;
+    int ret;
+    if (!(avctx->flags2 & AV_CODEC_FLAG2_ICC_PROFILES))
+        return 0;
+
+    sd = av_frame_get_side_data(frame, AV_FRAME_DATA_ICC_PROFILE);
+    if (!sd || !sd->size)
+        return 0;
+
+    if (!avci->icc.avctx) {
+        ret = ff_icc_context_init(&avci->icc, avctx);
+        if (ret < 0)
+            return ret;
+    }
+
+    profile = cmsOpenProfileFromMemTHR(avci->icc.ctx, sd->data, sd->size);
+    if (!profile)
+        return AVERROR_INVALIDDATA;
+
+    ret = ff_icc_profile_read_primaries(&avci->icc, profile, &coeffs);
+    if (!ret)
+        ret = ff_icc_profile_detect_transfer(&avci->icc, profile, &trc);
+    cmsCloseProfile(profile);
+    if (ret < 0)
+        return ret;
+
+    prim = av_csp_primaries_id_from_desc(&coeffs);
+    if (prim != AVCOL_PRI_UNSPECIFIED)
+        frame->color_primaries = prim;
+    if (trc != AVCOL_TRC_UNSPECIFIED)
+        frame->color_trc = trc;
+    return 0;
+}
+#else /* !CONFIG_LCMS2 */
+static int detect_colorspace(av_unused AVCodecContext *c, av_unused AVFrame *f)
+{
+    return 0;
+}
+#endif
+
+static int decode_simple_receive_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    int ret;
+    int64_t discarded_samples = 0;
+
+    while (!frame->buf[0]) {
+        if (discarded_samples > avctx->max_samples)
+            return AVERROR(EAGAIN);
+        ret = decode_simple_internal(avctx, frame, &discarded_samples);
+        if (ret < 0)
+            return ret;
+    }
+
+    return 0;
+}
+
+static int decode_receive_frame_internal(AVCodecContext *avctx, AVFrame *frame)
+{
+    AVCodecInternal *avci = avctx->internal;
+    const FFCodec *const codec = ffcodec(avctx->codec);
+    int ret, ok;
+
+    av_assert0(!frame->buf[0]);
+
+    if (codec->cb_type == FF_CODEC_CB_TYPE_RECEIVE_FRAME) {
+        ret = codec->cb.receive_frame(avctx, frame);
+    } else
+        ret = decode_simple_receive_frame(avctx, frame);
+
+    if (ret == AVERROR_EOF)
+        avci->draining_done = 1;
+
+    /* preserve ret */
+    ok = detect_colorspace(avctx, frame);
+    if (ok < 0) {
+        av_frame_unref(frame);
+        return ok;
+    }
+
+    if (!ret) {
+        frame->best_effort_timestamp = guess_correct_pts(avctx,
+                                                         frame->pts,
+                                                         frame->pkt_dts);
+
+#if FF_API_PKT_DURATION
+FF_DISABLE_DEPRECATION_WARNINGS
+        frame->pkt_duration = frame->duration;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+        /* the only case where decode data is not set should be decoders
+         * that do not call ff_get_buffer() */
+        av_assert0((frame->private_ref && frame->private_ref->size == sizeof(FrameDecodeData)) ||
+                   !(avctx->codec->capabilities & AV_CODEC_CAP_DR1));
+
+        if (frame->private_ref) {
+            FrameDecodeData *fdd = (FrameDecodeData*)frame->private_ref->data;
+
+            if (fdd->post_process) {
+                ret = fdd->post_process(avctx, frame);
+                if (ret < 0) {
+                    av_frame_unref(frame);
+                    return ret;
+                }
+            }
+        }
+    }
+
+    /* free the per-frame decode data */
+    av_buffer_unref(&frame->private_ref);
+
+    return ret;
+}
+
+int attribute_align_arg avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt)
+{
+    AVCodecInternal *avci = avctx->internal;
+    int ret;
+
+    if (!avcodec_is_open(avctx) || !av_codec_is_decoder(avctx->codec))
+        return AVERROR(EINVAL);
+
+    if (avctx->internal->draining)
+        return AVERROR_EOF;
+
+    if (avpkt && !avpkt->size && avpkt->data)
+        return AVERROR(EINVAL);
+
+    av_packet_unref(avci->buffer_pkt);
+    if (avpkt && (avpkt->data || avpkt->side_data_elems)) {
+        ret = av_packet_ref(avci->buffer_pkt, avpkt);
+        if (ret < 0)
+            return ret;
+    }
+
+    ret = av_bsf_send_packet(avci->bsf, avci->buffer_pkt);
+    if (ret < 0) {
+        av_packet_unref(avci->buffer_pkt);
+        return ret;
+    }
+
+    if (!avci->buffer_frame->buf[0]) {
+        ret = decode_receive_frame_internal(avctx, avci->buffer_frame);
+        if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF)
+            return ret;
+    }
+
+    return 0;
+}
+
+static int apply_cropping(AVCodecContext *avctx, AVFrame *frame)
+{
+    /* make sure we are noisy about decoders returning invalid cropping data */
+    if (frame->crop_left >= INT_MAX - frame->crop_right        ||
+        frame->crop_top  >= INT_MAX - frame->crop_bottom       ||
+        (frame->crop_left + frame->crop_right) >= frame->width ||
+        (frame->crop_top + frame->crop_bottom) >= frame->height) {
+        av_log(avctx, AV_LOG_WARNING,
+               "Invalid cropping information set by a decoder: "
+               "%"SIZE_SPECIFIER"/%"SIZE_SPECIFIER"/%"SIZE_SPECIFIER"/%"SIZE_SPECIFIER" "
+               "(frame size %dx%d). This is a bug, please report it\n",
+               frame->crop_left, frame->crop_right, frame->crop_top, frame->crop_bottom,
+               frame->width, frame->height);
+        frame->crop_left   = 0;
+        frame->crop_right  = 0;
+        frame->crop_top    = 0;
+        frame->crop_bottom = 0;
+        return 0;
+    }
+
+    if (!avctx->apply_cropping)
+        return 0;
+
+    return av_frame_apply_cropping(frame, avctx->flags & AV_CODEC_FLAG_UNALIGNED ?
+                                          AV_FRAME_CROP_UNALIGNED : 0);
+}
+
+// make sure frames returned to the caller are valid
+static int frame_validate(AVCodecContext *avctx, AVFrame *frame)
+{
+    if (!frame->buf[0] || frame->format < 0)
+        goto fail;
+
+    switch (avctx->codec_type) {
+    case AVMEDIA_TYPE_VIDEO:
+        if (frame->width <= 0 || frame->height <= 0)
+            goto fail;
+        break;
+    case AVMEDIA_TYPE_AUDIO:
+        if (!av_channel_layout_check(&frame->ch_layout) ||
+            frame->sample_rate <= 0)
+            goto fail;
+
+        break;
+    default: av_assert0(0);
+    }
+
+    return 0;
+fail:
+    av_log(avctx, AV_LOG_ERROR, "An invalid frame was output by a decoder. "
+           "This is a bug, please report it.\n");
+    return AVERROR_BUG;
+}
+
+int ff_decode_receive_frame(AVCodecContext *avctx, AVFrame *frame)
+{
+    AVCodecInternal *avci = avctx->internal;
+    int ret, changed;
+
+    if (!avcodec_is_open(avctx) || !av_codec_is_decoder(avctx->codec))
+        return AVERROR(EINVAL);
+
+    if (avci->buffer_frame->buf[0]) {
+        av_frame_move_ref(frame, avci->buffer_frame);
+    } else {
+        ret = decode_receive_frame_internal(avctx, frame);
+        if (ret < 0)
+            return ret;
+    }
+
+    ret = frame_validate(avctx, frame);
+    if (ret < 0)
+        goto fail;
+
+    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO) {
+        ret = apply_cropping(avctx, frame);
+        if (ret < 0)
+            goto fail;
+    }
+
+    avctx->frame_num++;
+#if FF_API_AVCTX_FRAME_NUMBER
+FF_DISABLE_DEPRECATION_WARNINGS
+    avctx->frame_number = avctx->frame_num;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+    if (avctx->flags & AV_CODEC_FLAG_DROPCHANGED) {
+
+        if (avctx->frame_num == 1) {
+            avci->initial_format = frame->format;
+            switch(avctx->codec_type) {
+            case AVMEDIA_TYPE_VIDEO:
+                avci->initial_width  = frame->width;
+                avci->initial_height = frame->height;
+                break;
+            case AVMEDIA_TYPE_AUDIO:
+                avci->initial_sample_rate = frame->sample_rate ? frame->sample_rate :
+                                                                 avctx->sample_rate;
+                ret = av_channel_layout_copy(&avci->initial_ch_layout, &frame->ch_layout);
+                if (ret < 0)
+                    goto fail;
+                break;
+            }
+        }
+
+        if (avctx->frame_num > 1) {
+            changed = avci->initial_format != frame->format;
+
+            switch(avctx->codec_type) {
+            case AVMEDIA_TYPE_VIDEO:
+                changed |= avci->initial_width  != frame->width ||
+                           avci->initial_height != frame->height;
+                break;
+            case AVMEDIA_TYPE_AUDIO:
+                changed |= avci->initial_sample_rate    != frame->sample_rate ||
+                           avci->initial_sample_rate    != avctx->sample_rate ||
+                           av_channel_layout_compare(&avci->initial_ch_layout, &frame->ch_layout);
+                break;
+            }
+
+            if (changed) {
+                avci->changed_frames_dropped++;
+                av_log(avctx, AV_LOG_INFO, "dropped changed frame #%"PRId64" pts %"PRId64
+                                            " drop count: %d \n",
+                                            avctx->frame_num, frame->pts,
+                                            avci->changed_frames_dropped);
+                ret = AVERROR_INPUT_CHANGED;
+                goto fail;
+            }
+        }
+    }
+    return 0;
+fail:
+    av_frame_unref(frame);
+    return ret;
+}
+
+static void get_subtitle_defaults(AVSubtitle *sub)
+{
+    memset(sub, 0, sizeof(*sub));
+    sub->pts = AV_NOPTS_VALUE;
+}
+
+#define UTF8_MAX_BYTES 4 /* 5 and 6 bytes sequences should not be used */
+static int recode_subtitle(AVCodecContext *avctx, const AVPacket **outpkt,
+                           const AVPacket *inpkt, AVPacket *buf_pkt)
+{
+#if CONFIG_ICONV
+    iconv_t cd = (iconv_t)-1;
+    int ret = 0;
+    char *inb, *outb;
+    size_t inl, outl;
+#endif
+
+    if (avctx->sub_charenc_mode != FF_SUB_CHARENC_MODE_PRE_DECODER || inpkt->size == 0) {
+        *outpkt = inpkt;
+        return 0;
+    }
+
+#if CONFIG_ICONV
+    inb = inpkt->data;
+    inl = inpkt->size;
+
+    if (inl >= INT_MAX / UTF8_MAX_BYTES - AV_INPUT_BUFFER_PADDING_SIZE) {
+        av_log(avctx, AV_LOG_ERROR, "Subtitles packet is too big for recoding\n");
+        return AVERROR(ERANGE);
+    }
+
+    cd = iconv_open("UTF-8", avctx->sub_charenc);
+    av_assert0(cd != (iconv_t)-1);
+
+    ret = av_new_packet(buf_pkt, inl * UTF8_MAX_BYTES);
+    if (ret < 0)
+        goto end;
+    ret = av_packet_copy_props(buf_pkt, inpkt);
+    if (ret < 0)
+        goto end;
+    outb = buf_pkt->data;
+    outl = buf_pkt->size;
+
+    if (iconv(cd, &inb, &inl, &outb, &outl) == (size_t)-1 ||
+        iconv(cd, NULL, NULL, &outb, &outl) == (size_t)-1 ||
+        outl >= buf_pkt->size || inl != 0) {
+        ret = FFMIN(AVERROR(errno), -1);
+        av_log(avctx, AV_LOG_ERROR, "Unable to recode subtitle event \"%s\" "
+               "from %s to UTF-8\n", inpkt->data, avctx->sub_charenc);
+        goto end;
+    }
+    buf_pkt->size -= outl;
+    memset(buf_pkt->data + buf_pkt->size, 0, outl);
+    *outpkt = buf_pkt;
+
+    ret = 0;
+end:
+    if (ret < 0)
+        av_packet_unref(buf_pkt);
+    if (cd != (iconv_t)-1)
+        iconv_close(cd);
+    return ret;
+#else
+    av_log(avctx, AV_LOG_ERROR, "requesting subtitles recoding without iconv");
+    return AVERROR(EINVAL);
+#endif
+}
+
+static int utf8_check(const uint8_t *str)
+{
+    const uint8_t *byte;
+    uint32_t codepoint, min;
+
+    while (*str) {
+        byte = str;
+        GET_UTF8(codepoint, *(byte++), return 0;);
+        min = byte - str == 1 ? 0 : byte - str == 2 ? 0x80 :
+              1 << (5 * (byte - str) - 4);
+        if (codepoint < min || codepoint >= 0x110000 ||
+            codepoint == 0xFFFE /* BOM */ ||
+            codepoint >= 0xD800 && codepoint <= 0xDFFF /* surrogates */)
+            return 0;
+        str = byte;
+    }
+    return 1;
+}
+
+int avcodec_decode_subtitle2(AVCodecContext *avctx, AVSubtitle *sub,
+                             int *got_sub_ptr, const AVPacket *avpkt)
+{
+    int ret = 0;
+
+    if (!avpkt->data && avpkt->size) {
+        av_log(avctx, AV_LOG_ERROR, "invalid packet: NULL data, size != 0\n");
+        return AVERROR(EINVAL);
+    }
+    if (!avctx->codec)
+        return AVERROR(EINVAL);
+    if (avctx->codec->type != AVMEDIA_TYPE_SUBTITLE) {
+        av_log(avctx, AV_LOG_ERROR, "Invalid media type for subtitles\n");
+        return AVERROR(EINVAL);
+    }
+
+    *got_sub_ptr = 0;
+    get_subtitle_defaults(sub);
+
+    if ((avctx->codec->capabilities & AV_CODEC_CAP_DELAY) || avpkt->size) {
+        AVCodecInternal *avci = avctx->internal;
+        const AVPacket *pkt;
+
+        ret = recode_subtitle(avctx, &pkt, avpkt, avci->buffer_pkt);
+        if (ret < 0)
+            return ret;
+
+        if (avctx->pkt_timebase.num && avpkt->pts != AV_NOPTS_VALUE)
+            sub->pts = av_rescale_q(avpkt->pts,
+                                    avctx->pkt_timebase, AV_TIME_BASE_Q);
+        ret = ffcodec(avctx->codec)->cb.decode_sub(avctx, sub, got_sub_ptr, pkt);
+        if (pkt == avci->buffer_pkt) // did we recode?
+            av_packet_unref(avci->buffer_pkt);
+        if (ret < 0) {
+            *got_sub_ptr = 0;
+            avsubtitle_free(sub);
+            return ret;
+        }
+        av_assert1(!sub->num_rects || *got_sub_ptr);
+
+        if (sub->num_rects && !sub->end_display_time && avpkt->duration &&
+            avctx->pkt_timebase.num) {
+            AVRational ms = { 1, 1000 };
+            sub->end_display_time = av_rescale_q(avpkt->duration,
+                                                 avctx->pkt_timebase, ms);
+        }
+
+        if (avctx->codec_descriptor->props & AV_CODEC_PROP_BITMAP_SUB)
+            sub->format = 0;
+        else if (avctx->codec_descriptor->props & AV_CODEC_PROP_TEXT_SUB)
+            sub->format = 1;
+
+        for (unsigned i = 0; i < sub->num_rects; i++) {
+            if (avctx->sub_charenc_mode != FF_SUB_CHARENC_MODE_IGNORE &&
+                sub->rects[i]->ass && !utf8_check(sub->rects[i]->ass)) {
+                av_log(avctx, AV_LOG_ERROR,
+                       "Invalid UTF-8 in decoded subtitles text; "
+                       "maybe missing -sub_charenc option\n");
+                avsubtitle_free(sub);
+                *got_sub_ptr = 0;
+                return AVERROR_INVALIDDATA;
+            }
+        }
+
+        if (*got_sub_ptr)
+            avctx->frame_num++;
+#if FF_API_AVCTX_FRAME_NUMBER
+FF_DISABLE_DEPRECATION_WARNINGS
+        avctx->frame_number = avctx->frame_num;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+    }
+
+    return ret;
+}
+
+enum AVPixelFormat avcodec_default_get_format(struct AVCodecContext *avctx,
+                                              const enum AVPixelFormat *fmt)
+{
+    const AVPixFmtDescriptor *desc;
+    const AVCodecHWConfig *config;
+    int i, n;
+
+    // If a device was supplied when the codec was opened, assume that the
+    // user wants to use it.
+    if (avctx->hw_device_ctx && ffcodec(avctx->codec)->hw_configs) {
+        AVHWDeviceContext *device_ctx =
+            (AVHWDeviceContext*)avctx->hw_device_ctx->data;
+        for (i = 0;; i++) {
+            config = &ffcodec(avctx->codec)->hw_configs[i]->public;
+            if (!config)
+                break;
+            if (!(config->methods &
+                  AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX))
+                continue;
+            if (device_ctx->type != config->device_type)
+                continue;
+            for (n = 0; fmt[n] != AV_PIX_FMT_NONE; n++) {
+                if (config->pix_fmt == fmt[n])
+                    return fmt[n];
+            }
+        }
+    }
+    // No device or other setup, so we have to choose from things which
+    // don't any other external information.
+
+    // If the last element of the list is a software format, choose it
+    // (this should be best software format if any exist).
+    for (n = 0; fmt[n] != AV_PIX_FMT_NONE; n++);
+    desc = av_pix_fmt_desc_get(fmt[n - 1]);
+    if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL))
+        return fmt[n - 1];
+
+    // Finally, traverse the list in order and choose the first entry
+    // with no external dependencies (if there is no hardware configuration
+    // information available then this just picks the first entry).
+    for (n = 0; fmt[n] != AV_PIX_FMT_NONE; n++) {
+        for (i = 0;; i++) {
+            config = avcodec_get_hw_config(avctx->codec, i);
+            if (!config)
+                break;
+            if (config->pix_fmt == fmt[n])
+                break;
+        }
+        if (!config) {
+            // No specific config available, so the decoder must be able
+            // to handle this format without any additional setup.
+            return fmt[n];
+        }
+        if (config->methods & AV_CODEC_HW_CONFIG_METHOD_INTERNAL) {
+            // Usable with only internal setup.
+            return fmt[n];
+        }
+    }
+
+    // Nothing is usable, give up.
+    return AV_PIX_FMT_NONE;
+}
+
+int ff_decode_get_hw_frames_ctx(AVCodecContext *avctx,
+                                enum AVHWDeviceType dev_type)
+{
+    AVHWDeviceContext *device_ctx;
+    AVHWFramesContext *frames_ctx;
+    int ret;
+
+    if (!avctx->hwaccel)
+        return AVERROR(ENOSYS);
+
+    if (avctx->hw_frames_ctx)
+        return 0;
+    if (!avctx->hw_device_ctx) {
+        av_log(avctx, AV_LOG_ERROR, "A hardware frames or device context is "
+                "required for hardware accelerated decoding.\n");
+        return AVERROR(EINVAL);
+    }
+
+    device_ctx = (AVHWDeviceContext *)avctx->hw_device_ctx->data;
+    if (device_ctx->type != dev_type) {
+        av_log(avctx, AV_LOG_ERROR, "Device type %s expected for hardware "
+               "decoding, but got %s.\n", av_hwdevice_get_type_name(dev_type),
+               av_hwdevice_get_type_name(device_ctx->type));
+        return AVERROR(EINVAL);
+    }
+
+    ret = avcodec_get_hw_frames_parameters(avctx,
+                                           avctx->hw_device_ctx,
+                                           avctx->hwaccel->pix_fmt,
+                                           &avctx->hw_frames_ctx);
+    if (ret < 0)
+        return ret;
+
+    frames_ctx = (AVHWFramesContext*)avctx->hw_frames_ctx->data;
+
+
+    if (frames_ctx->initial_pool_size) {
+        // We guarantee 4 base work surfaces. The function above guarantees 1
+        // (the absolute minimum), so add the missing count.
+        frames_ctx->initial_pool_size += 3;
+    }
+
+    ret = av_hwframe_ctx_init(avctx->hw_frames_ctx);
+    if (ret < 0) {
+        av_buffer_unref(&avctx->hw_frames_ctx);
+        return ret;
+    }
+
+    return 0;
+}
+
+int avcodec_get_hw_frames_parameters(AVCodecContext *avctx,
+                                     AVBufferRef *device_ref,
+                                     enum AVPixelFormat hw_pix_fmt,
+                                     AVBufferRef **out_frames_ref)
+{
+    AVBufferRef *frames_ref = NULL;
+    const AVCodecHWConfigInternal *hw_config;
+    const AVHWAccel *hwa;
+    int i, ret;
+
+    for (i = 0;; i++) {
+        hw_config = ffcodec(avctx->codec)->hw_configs[i];
+        if (!hw_config)
+            return AVERROR(ENOENT);
+        if (hw_config->public.pix_fmt == hw_pix_fmt)
+            break;
+    }
+
+    hwa = hw_config->hwaccel;
+    if (!hwa || !hwa->frame_params)
+        return AVERROR(ENOENT);
+
+    frames_ref = av_hwframe_ctx_alloc(device_ref);
+    if (!frames_ref)
+        return AVERROR(ENOMEM);
+
+    ret = hwa->frame_params(avctx, frames_ref);
+    if (ret >= 0) {
+        AVHWFramesContext *frames_ctx = (AVHWFramesContext*)frames_ref->data;
+
+        if (frames_ctx->initial_pool_size) {
+            // If the user has requested that extra output surfaces be
+            // available then add them here.
+            if (avctx->extra_hw_frames > 0)
+                frames_ctx->initial_pool_size += avctx->extra_hw_frames;
+
+            // If frame threading is enabled then an extra surface per thread
+            // is also required.
+            if (avctx->active_thread_type & FF_THREAD_FRAME)
+                frames_ctx->initial_pool_size += avctx->thread_count;
+        }
+
+        *out_frames_ref = frames_ref;
+    } else {
+        av_buffer_unref(&frames_ref);
+    }
+    return ret;
+}
+
+static int hwaccel_init(AVCodecContext *avctx,
+                        const AVCodecHWConfigInternal *hw_config)
+{
+    const AVHWAccel *hwaccel;
+    int err;
+
+    hwaccel = hw_config->hwaccel;
+    if (hwaccel->capabilities & AV_HWACCEL_CODEC_CAP_EXPERIMENTAL &&
+        avctx->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {
+        av_log(avctx, AV_LOG_WARNING, "Ignoring experimental hwaccel: %s\n",
+               hwaccel->name);
+        return AVERROR_PATCHWELCOME;
+    }
+
+    if (hwaccel->priv_data_size) {
+        avctx->internal->hwaccel_priv_data =
+            av_mallocz(hwaccel->priv_data_size);
+        if (!avctx->internal->hwaccel_priv_data)
+            return AVERROR(ENOMEM);
+    }
+
+    avctx->hwaccel = hwaccel;
+    if (hwaccel->init) {
+        err = hwaccel->init(avctx);
+        if (err < 0) {
+            av_log(avctx, AV_LOG_ERROR, "Failed setup for format %s: "
+                   "hwaccel initialisation returned error.\n",
+                   av_get_pix_fmt_name(hw_config->public.pix_fmt));
+            av_freep(&avctx->internal->hwaccel_priv_data);
+            avctx->hwaccel = NULL;
+            return err;
+        }
+    }
+
+    return 0;
+}
+
+static void hwaccel_uninit(AVCodecContext *avctx)
+{
+    if (avctx->hwaccel && avctx->hwaccel->uninit)
+        avctx->hwaccel->uninit(avctx);
+
+    av_freep(&avctx->internal->hwaccel_priv_data);
+
+    avctx->hwaccel = NULL;
+
+    av_buffer_unref(&avctx->hw_frames_ctx);
+}
+
+int ff_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt)
+{
+    const AVPixFmtDescriptor *desc;
+    enum AVPixelFormat *choices;
+    enum AVPixelFormat ret, user_choice;
+    const AVCodecHWConfigInternal *hw_config;
+    const AVCodecHWConfig *config;
+    int i, n, err;
+
+    // Find end of list.
+    for (n = 0; fmt[n] != AV_PIX_FMT_NONE; n++);
+    // Must contain at least one entry.
+    av_assert0(n >= 1);
+    // If a software format is available, it must be the last entry.
+    desc = av_pix_fmt_desc_get(fmt[n - 1]);
+    if (desc->flags & AV_PIX_FMT_FLAG_HWACCEL) {
+        // No software format is available.
+    } else {
+        avctx->sw_pix_fmt = fmt[n - 1];
+    }
+
+    choices = av_memdup(fmt, (n + 1) * sizeof(*choices));
+    if (!choices)
+        return AV_PIX_FMT_NONE;
+
+    for (;;) {
+        // Remove the previous hwaccel, if there was one.
+        hwaccel_uninit(avctx);
+
+        user_choice = avctx->get_format(avctx, choices);
+        if (user_choice == AV_PIX_FMT_NONE) {
+            // Explicitly chose nothing, give up.
+            ret = AV_PIX_FMT_NONE;
+            break;
+        }
+
+        desc = av_pix_fmt_desc_get(user_choice);
+        if (!desc) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid format returned by "
+                   "get_format() callback.\n");
+            ret = AV_PIX_FMT_NONE;
+            break;
+        }
+        av_log(avctx, AV_LOG_DEBUG, "Format %s chosen by get_format().\n",
+               desc->name);
+
+        for (i = 0; i < n; i++) {
+            if (choices[i] == user_choice)
+                break;
+        }
+        if (i == n) {
+            av_log(avctx, AV_LOG_ERROR, "Invalid return from get_format(): "
+                   "%s not in possible list.\n", desc->name);
+            ret = AV_PIX_FMT_NONE;
+            break;
+        }
+
+        if (ffcodec(avctx->codec)->hw_configs) {
+            for (i = 0;; i++) {
+                hw_config = ffcodec(avctx->codec)->hw_configs[i];
+                if (!hw_config)
+                    break;
+                if (hw_config->public.pix_fmt == user_choice)
+                    break;
+            }
+        } else {
+            hw_config = NULL;
+        }
+
+        if (!hw_config) {
+            // No config available, so no extra setup required.
+            ret = user_choice;
+            break;
+        }
+        config = &hw_config->public;
+
+        if (config->methods &
+            AV_CODEC_HW_CONFIG_METHOD_HW_FRAMES_CTX &&
+            avctx->hw_frames_ctx) {
+            const AVHWFramesContext *frames_ctx =
+                (AVHWFramesContext*)avctx->hw_frames_ctx->data;
+            if (frames_ctx->format != user_choice) {
+                av_log(avctx, AV_LOG_ERROR, "Invalid setup for format %s: "
+                       "does not match the format of the provided frames "
+                       "context.\n", desc->name);
+                goto try_again;
+            }
+        } else if (config->methods &
+                   AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX &&
+                   avctx->hw_device_ctx) {
+            const AVHWDeviceContext *device_ctx =
+                (AVHWDeviceContext*)avctx->hw_device_ctx->data;
+            if (device_ctx->type != config->device_type) {
+                av_log(avctx, AV_LOG_ERROR, "Invalid setup for format %s: "
+                       "does not match the type of the provided device "
+                       "context.\n", desc->name);
+                goto try_again;
+            }
+        } else if (config->methods &
+                   AV_CODEC_HW_CONFIG_METHOD_INTERNAL) {
+            // Internal-only setup, no additional configuration.
+        } else if (config->methods &
+                   AV_CODEC_HW_CONFIG_METHOD_AD_HOC) {
+            // Some ad-hoc configuration we can't see and can't check.
+        } else {
+            av_log(avctx, AV_LOG_ERROR, "Invalid setup for format %s: "
+                   "missing configuration.\n", desc->name);
+            goto try_again;
+        }
+        if (hw_config->hwaccel) {
+            av_log(avctx, AV_LOG_DEBUG, "Format %s requires hwaccel "
+                   "initialisation.\n", desc->name);
+            err = hwaccel_init(avctx, hw_config);
+            if (err < 0)
+                goto try_again;
+        }
+        ret = user_choice;
+        break;
+
+    try_again:
+        av_log(avctx, AV_LOG_DEBUG, "Format %s not usable, retrying "
+               "get_format() without it.\n", desc->name);
+        for (i = 0; i < n; i++) {
+            if (choices[i] == user_choice)
+                break;
+        }
+        for (; i + 1 < n; i++)
+            choices[i] = choices[i + 1];
+        --n;
+    }
+
+    av_freep(&choices);
+    return ret;
+}
+
+static int add_metadata_from_side_data(const AVPacket *avpkt, AVFrame *frame)
+{
+    size_t size;
+    const uint8_t *side_metadata;
+
+    AVDictionary **frame_md = &frame->metadata;
+
+    side_metadata = av_packet_get_side_data(avpkt,
+                                            AV_PKT_DATA_STRINGS_METADATA, &size);
+    return av_packet_unpack_dictionary(side_metadata, size, frame_md);
+}
+
+int ff_decode_frame_props_from_pkt(const AVCodecContext *avctx,
+                                   AVFrame *frame, const AVPacket *pkt)
+{
+    static const struct {
+        enum AVPacketSideDataType packet;
+        enum AVFrameSideDataType frame;
+    } sd[] = {
+        { AV_PKT_DATA_REPLAYGAIN ,                AV_FRAME_DATA_REPLAYGAIN },
+        { AV_PKT_DATA_DISPLAYMATRIX,              AV_FRAME_DATA_DISPLAYMATRIX },
+        { AV_PKT_DATA_SPHERICAL,                  AV_FRAME_DATA_SPHERICAL },
+        { AV_PKT_DATA_STEREO3D,                   AV_FRAME_DATA_STEREO3D },
+        { AV_PKT_DATA_AUDIO_SERVICE_TYPE,         AV_FRAME_DATA_AUDIO_SERVICE_TYPE },
+        { AV_PKT_DATA_MASTERING_DISPLAY_METADATA, AV_FRAME_DATA_MASTERING_DISPLAY_METADATA },
+        { AV_PKT_DATA_CONTENT_LIGHT_LEVEL,        AV_FRAME_DATA_CONTENT_LIGHT_LEVEL },
+        { AV_PKT_DATA_A53_CC,                     AV_FRAME_DATA_A53_CC },
+        { AV_PKT_DATA_ICC_PROFILE,                AV_FRAME_DATA_ICC_PROFILE },
+        { AV_PKT_DATA_S12M_TIMECODE,              AV_FRAME_DATA_S12M_TIMECODE },
+        { AV_PKT_DATA_DYNAMIC_HDR10_PLUS,         AV_FRAME_DATA_DYNAMIC_HDR_PLUS },
+    };
+
+    frame->pts          = pkt->pts;
+    frame->pkt_pos      = pkt->pos;
+    frame->duration     = pkt->duration;
+    frame->pkt_size     = pkt->size;
+
+    for (int i = 0; i < FF_ARRAY_ELEMS(sd); i++) {
+        size_t size;
+        uint8_t *packet_sd = av_packet_get_side_data(pkt, sd[i].packet, &size);
+        if (packet_sd) {
+            AVFrameSideData *frame_sd = av_frame_new_side_data(frame,
+                                                               sd[i].frame,
+                                                               size);
+            if (!frame_sd)
+                return AVERROR(ENOMEM);
+
+            memcpy(frame_sd->data, packet_sd, size);
+        }
+    }
+    add_metadata_from_side_data(pkt, frame);
+
+    if (pkt->flags & AV_PKT_FLAG_DISCARD) {
+        frame->flags |= AV_FRAME_FLAG_DISCARD;
+    } else {
+        frame->flags = (frame->flags & ~AV_FRAME_FLAG_DISCARD);
+    }
+
+    if (avctx->flags & AV_CODEC_FLAG_COPY_OPAQUE) {
+        int ret = av_buffer_replace(&frame->opaque_ref, pkt->opaque_ref);
+        if (ret < 0)
+            return ret;
+        frame->opaque = pkt->opaque;
+    }
+
+    return 0;
+}
+
+int ff_decode_frame_props(AVCodecContext *avctx, AVFrame *frame)
+{
+    const AVPacket *pkt = avctx->internal->last_pkt_props;
+
+    if (!(ffcodec(avctx->codec)->caps_internal & FF_CODEC_CAP_SETS_FRAME_PROPS)) {
+        int ret = ff_decode_frame_props_from_pkt(avctx, frame, pkt);
+        if (ret < 0)
+            return ret;
+        frame->pkt_size     = (int)(intptr_t)pkt->opaque;
+    }
+#if FF_API_REORDERED_OPAQUE
+FF_DISABLE_DEPRECATION_WARNINGS
+    frame->reordered_opaque = avctx->reordered_opaque;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+    if (frame->color_primaries == AVCOL_PRI_UNSPECIFIED)
+        frame->color_primaries = avctx->color_primaries;
+    if (frame->color_trc == AVCOL_TRC_UNSPECIFIED)
+        frame->color_trc = avctx->color_trc;
+    if (frame->colorspace == AVCOL_SPC_UNSPECIFIED)
+        frame->colorspace = avctx->colorspace;
+    if (frame->color_range == AVCOL_RANGE_UNSPECIFIED)
+        frame->color_range = avctx->color_range;
+    if (frame->chroma_location == AVCHROMA_LOC_UNSPECIFIED)
+        frame->chroma_location = avctx->chroma_sample_location;
+
+    switch (avctx->codec->type) {
+    case AVMEDIA_TYPE_VIDEO:
+        frame->format              = avctx->pix_fmt;
+        if (!frame->sample_aspect_ratio.num)
+            frame->sample_aspect_ratio = avctx->sample_aspect_ratio;
+
+        if (frame->width && frame->height &&
+            av_image_check_sar(frame->width, frame->height,
+                               frame->sample_aspect_ratio) < 0) {
+            av_log(avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
+                   frame->sample_aspect_ratio.num,
+                   frame->sample_aspect_ratio.den);
+            frame->sample_aspect_ratio = (AVRational){ 0, 1 };
+        }
+
+        break;
+    case AVMEDIA_TYPE_AUDIO:
+        if (!frame->sample_rate)
+            frame->sample_rate    = avctx->sample_rate;
+        if (frame->format < 0)
+            frame->format         = avctx->sample_fmt;
+        if (!frame->ch_layout.nb_channels) {
+            int ret = av_channel_layout_copy(&frame->ch_layout, &avctx->ch_layout);
+            if (ret < 0)
+                return ret;
+        }
+#if FF_API_OLD_CHANNEL_LAYOUT
+FF_DISABLE_DEPRECATION_WARNINGS
+        frame->channels = frame->ch_layout.nb_channels;
+        frame->channel_layout = frame->ch_layout.order == AV_CHANNEL_ORDER_NATIVE ?
+                                frame->ch_layout.u.mask : 0;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+        break;
+    }
+    return 0;
+}
+
+static void validate_avframe_allocation(AVCodecContext *avctx, AVFrame *frame)
+{
+    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO) {
+        int i;
+        int num_planes = av_pix_fmt_count_planes(frame->format);
+        const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
+        int flags = desc ? desc->flags : 0;
+        if (num_planes == 1 && (flags & AV_PIX_FMT_FLAG_PAL))
+            num_planes = 2;
+        for (i = 0; i < num_planes; i++) {
+            av_assert0(frame->data[i]);
+        }
+        // For formats without data like hwaccel allow unused pointers to be non-NULL.
+        for (i = num_planes; num_planes > 0 && i < FF_ARRAY_ELEMS(frame->data); i++) {
+            if (frame->data[i])
+                av_log(avctx, AV_LOG_ERROR, "Buffer returned by get_buffer2() did not zero unused plane pointers\n");
+            frame->data[i] = NULL;
+        }
+    }
+}
+
+static void decode_data_free(void *opaque, uint8_t *data)
+{
+    FrameDecodeData *fdd = (FrameDecodeData*)data;
+
+    if (fdd->post_process_opaque_free)
+        fdd->post_process_opaque_free(fdd->post_process_opaque);
+
+    if (fdd->hwaccel_priv_free)
+        fdd->hwaccel_priv_free(fdd->hwaccel_priv);
+
+    av_freep(&fdd);
+}
+
+int ff_attach_decode_data(AVFrame *frame)
+{
+    AVBufferRef *fdd_buf;
+    FrameDecodeData *fdd;
+
+    av_assert1(!frame->private_ref);
+    av_buffer_unref(&frame->private_ref);
+
+    fdd = av_mallocz(sizeof(*fdd));
+    if (!fdd)
+        return AVERROR(ENOMEM);
+
+    fdd_buf = av_buffer_create((uint8_t*)fdd, sizeof(*fdd), decode_data_free,
+                               NULL, AV_BUFFER_FLAG_READONLY);
+    if (!fdd_buf) {
+        av_freep(&fdd);
+        return AVERROR(ENOMEM);
+    }
+
+    frame->private_ref = fdd_buf;
+
+    return 0;
+}
+
+int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
+{
+    const AVHWAccel *hwaccel = avctx->hwaccel;
+    int override_dimensions = 1;
+    int ret;
+
+    av_assert0(av_codec_is_decoder(avctx->codec));
+
+    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO) {
+        if ((unsigned)avctx->width > INT_MAX - STRIDE_ALIGN ||
+            (ret = av_image_check_size2(FFALIGN(avctx->width, STRIDE_ALIGN), avctx->height, avctx->max_pixels, AV_PIX_FMT_NONE, 0, avctx)) < 0 || avctx->pix_fmt<0) {
+            av_log(avctx, AV_LOG_ERROR, "video_get_buffer: image parameters invalid\n");
+            ret = AVERROR(EINVAL);
+            goto fail;
+        }
+
+        if (frame->width <= 0 || frame->height <= 0) {
+            frame->width  = FFMAX(avctx->width,  AV_CEIL_RSHIFT(avctx->coded_width,  avctx->lowres));
+            frame->height = FFMAX(avctx->height, AV_CEIL_RSHIFT(avctx->coded_height, avctx->lowres));
+            override_dimensions = 0;
+        }
+
+        if (frame->data[0] || frame->data[1] || frame->data[2] || frame->data[3]) {
+            av_log(avctx, AV_LOG_ERROR, "pic->data[*]!=NULL in get_buffer_internal\n");
+            ret = AVERROR(EINVAL);
+            goto fail;
+        }
+    } else if (avctx->codec_type == AVMEDIA_TYPE_AUDIO) {
+#if FF_API_OLD_CHANNEL_LAYOUT
+FF_DISABLE_DEPRECATION_WARNINGS
+        /* compat layer for old-style get_buffer() implementations */
+        avctx->channels = avctx->ch_layout.nb_channels;
+        avctx->channel_layout = (avctx->ch_layout.order == AV_CHANNEL_ORDER_NATIVE) ?
+                                avctx->ch_layout.u.mask : 0;
+FF_ENABLE_DEPRECATION_WARNINGS
+#endif
+
+        if (frame->nb_samples * (int64_t)avctx->ch_layout.nb_channels > avctx->max_samples) {
+            av_log(avctx, AV_LOG_ERROR, "samples per frame %d, exceeds max_samples %"PRId64"\n", frame->nb_samples, avctx->max_samples);
+            ret = AVERROR(EINVAL);
+            goto fail;
+        }
+    }
+    ret = ff_decode_frame_props(avctx, frame);
+    if (ret < 0)
+        goto fail;
+
+    if (hwaccel) {
+        if (hwaccel->alloc_frame) {
+            ret = hwaccel->alloc_frame(avctx, frame);
+            goto end;
+        }
+    } else
+        avctx->sw_pix_fmt = avctx->pix_fmt;
+
+    ret = avctx->get_buffer2(avctx, frame, flags);
+    if (ret < 0)
+        goto fail;
+
+    validate_avframe_allocation(avctx, frame);
+
+    ret = ff_attach_decode_data(frame);
+    if (ret < 0)
+        goto fail;
+
+end:
+    if (avctx->codec_type == AVMEDIA_TYPE_VIDEO && !override_dimensions &&
+        !(ffcodec(avctx->codec)->caps_internal & FF_CODEC_CAP_EXPORTS_CROPPING)) {
+        frame->width  = avctx->width;
+        frame->height = avctx->height;
+    }
+
+fail:
+    if (ret < 0) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+        av_frame_unref(frame);
+    }
+
+    return ret;
+}
+
+static int reget_buffer_internal(AVCodecContext *avctx, AVFrame *frame, int flags)
+{
+    AVFrame *tmp;
+    int ret;
+
+    av_assert0(avctx->codec_type == AVMEDIA_TYPE_VIDEO);
+
+    if (frame->data[0] && (frame->width != avctx->width || frame->height != avctx->height || frame->format != avctx->pix_fmt)) {
+        av_log(avctx, AV_LOG_WARNING, "Picture changed from size:%dx%d fmt:%s to size:%dx%d fmt:%s in reget buffer()\n",
+               frame->width, frame->height, av_get_pix_fmt_name(frame->format), avctx->width, avctx->height, av_get_pix_fmt_name(avctx->pix_fmt));
+        av_frame_unref(frame);
+    }
+
+    if (!frame->data[0])
+        return ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF);
+
+    if ((flags & FF_REGET_BUFFER_FLAG_READONLY) || av_frame_is_writable(frame))
+        return ff_decode_frame_props(avctx, frame);
+
+    tmp = av_frame_alloc();
+    if (!tmp)
+        return AVERROR(ENOMEM);
+
+    av_frame_move_ref(tmp, frame);
+
+    ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF);
+    if (ret < 0) {
+        av_frame_free(&tmp);
+        return ret;
+    }
+
+    av_frame_copy(frame, tmp);
+    av_frame_free(&tmp);
+
+    return 0;
+}
+
+int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
+{
+    int ret = reget_buffer_internal(avctx, frame, flags);
+    if (ret < 0)
+        av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
+    return ret;
+}
+
+int ff_decode_preinit(AVCodecContext *avctx)
+{
+    AVCodecInternal *avci = avctx->internal;
+    int ret = 0;
+
+    /* if the decoder init function was already called previously,
+     * free the already allocated subtitle_header before overwriting it */
+    av_freep(&avctx->subtitle_header);
+
+    if (avctx->codec->max_lowres < avctx->lowres || avctx->lowres < 0) {
+        av_log(avctx, AV_LOG_WARNING, "The maximum value for lowres supported by the decoder is %d\n",
+               avctx->codec->max_lowres);
+        avctx->lowres = avctx->codec->max_lowres;
+    }
+    if (avctx->sub_charenc) {
+        if (avctx->codec_type != AVMEDIA_TYPE_SUBTITLE) {
+            av_log(avctx, AV_LOG_ERROR, "Character encoding is only "
+                   "supported with subtitles codecs\n");
+            return AVERROR(EINVAL);
+        } else if (avctx->codec_descriptor->props & AV_CODEC_PROP_BITMAP_SUB) {
+            av_log(avctx, AV_LOG_WARNING, "Codec '%s' is bitmap-based, "
+                   "subtitles character encoding will be ignored\n",
+                   avctx->codec_descriptor->name);
+            avctx->sub_charenc_mode = FF_SUB_CHARENC_MODE_DO_NOTHING;
+        } else {
+            /* input character encoding is set for a text based subtitle
+             * codec at this point */
+            if (avctx->sub_charenc_mode == FF_SUB_CHARENC_MODE_AUTOMATIC)
+                avctx->sub_charenc_mode = FF_SUB_CHARENC_MODE_PRE_DECODER;
+
+            if (avctx->sub_charenc_mode == FF_SUB_CHARENC_MODE_PRE_DECODER) {
+#if CONFIG_ICONV
+                iconv_t cd = iconv_open("UTF-8", avctx->sub_charenc);
+                if (cd == (iconv_t)-1) {
+                    ret = AVERROR(errno);
+                    av_log(avctx, AV_LOG_ERROR, "Unable to open iconv context "
+                           "with input character encoding \"%s\"\n", avctx->sub_charenc);
+                    return ret;
+                }
+                iconv_close(cd);
+#else
+                av_log(avctx, AV_LOG_ERROR, "Character encoding subtitles "
+                       "conversion needs a libavcodec built with iconv support "
+                       "for this codec\n");
+                return AVERROR(ENOSYS);
+#endif
+            }
+        }
+    }
+
+    avctx->pts_correction_num_faulty_pts =
+    avctx->pts_correction_num_faulty_dts = 0;
+    avctx->pts_correction_last_pts =
+    avctx->pts_correction_last_dts = INT64_MIN;
+
+    if (   !CONFIG_GRAY && avctx->flags & AV_CODEC_FLAG_GRAY
+        && avctx->codec_descriptor->type == AVMEDIA_TYPE_VIDEO)
+        av_log(avctx, AV_LOG_WARNING,
+               "gray decoding requested but not enabled at configuration time\n");
+    if (avctx->flags2 & AV_CODEC_FLAG2_EXPORT_MVS) {
+        avctx->export_side_data |= AV_CODEC_EXPORT_DATA_MVS;
+    }
+
+    avci->in_pkt         = av_packet_alloc();
+    avci->last_pkt_props = av_packet_alloc();
+    if (!avci->in_pkt || !avci->last_pkt_props)
+        return AVERROR(ENOMEM);
+
+    ret = decode_bsfs_init(avctx);
+    if (ret < 0)
+        return ret;
+
+    return 0;
+}
+
+int ff_copy_palette(void *dst, const AVPacket *src, void *logctx)
+{
+    size_t size;
+    const void *pal = av_packet_get_side_data(src, AV_PKT_DATA_PALETTE, &size);
+
+    if (pal && size == AVPALETTE_SIZE) {
+        memcpy(dst, pal, AVPALETTE_SIZE);
+        return 1;
+    } else if (pal) {
+        av_log(logctx, AV_LOG_ERROR,
+               "Palette size %"SIZE_SPECIFIER" is wrong\n", size);
+    }
+    return 0;
+}