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path: root/third_party/dav1d/src/lf_apply_tmpl.c
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/*
 * Copyright © 2018, VideoLAN and dav1d authors
 * Copyright © 2018, Two Orioles, LLC
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"

#include <string.h>

#include "common/intops.h"

#include "src/lf_apply.h"
#include "src/lr_apply.h"

// The loop filter buffer stores 12 rows of pixels. A superblock block will
// contain at most 2 stripes. Each stripe requires 4 rows pixels (2 above
// and 2 below) the final 4 rows are used to swap the bottom of the last
// stripe with the top of the next super block row.
static void backup_lpf(const Dav1dFrameContext *const f,
                       pixel *dst, const ptrdiff_t dst_stride,
                       const pixel *src, const ptrdiff_t src_stride,
                       const int ss_ver, const int sb128,
                       int row, const int row_h, const int src_w,
                       const int h, const int ss_hor, const int lr_backup)
{
    const int cdef_backup = !lr_backup;
    const int dst_w = f->frame_hdr->super_res.enabled ?
                      (f->frame_hdr->width[1] + ss_hor) >> ss_hor : src_w;

    // The first stripe of the frame is shorter by 8 luma pixel rows.
    int stripe_h = ((64 << (cdef_backup & sb128)) - 8 * !row) >> ss_ver;
    src += (stripe_h - 2) * PXSTRIDE(src_stride);

    if (f->c->n_tc == 1) {
        if (row) {
            const int top = 4 << sb128;
            // Copy the top part of the stored loop filtered pixels from the
            // previous sb row needed above the first stripe of this sb row.
            pixel_copy(&dst[PXSTRIDE(dst_stride) *  0],
                       &dst[PXSTRIDE(dst_stride) *  top],      dst_w);
            pixel_copy(&dst[PXSTRIDE(dst_stride) *  1],
                       &dst[PXSTRIDE(dst_stride) * (top + 1)], dst_w);
            pixel_copy(&dst[PXSTRIDE(dst_stride) *  2],
                       &dst[PXSTRIDE(dst_stride) * (top + 2)], dst_w);
            pixel_copy(&dst[PXSTRIDE(dst_stride) *  3],
                       &dst[PXSTRIDE(dst_stride) * (top + 3)], dst_w);
        }
        dst += 4 * PXSTRIDE(dst_stride);
    }

    if (lr_backup && (f->frame_hdr->width[0] != f->frame_hdr->width[1])) {
        while (row + stripe_h <= row_h) {
            const int n_lines = 4 - (row + stripe_h + 1 == h);
            f->dsp->mc.resize(dst, dst_stride, src, src_stride,
                              dst_w, n_lines, src_w, f->resize_step[ss_hor],
                              f->resize_start[ss_hor] HIGHBD_CALL_SUFFIX);
            row += stripe_h; // unmodified stripe_h for the 1st stripe
            stripe_h = 64 >> ss_ver;
            src += stripe_h * PXSTRIDE(src_stride);
            dst += n_lines * PXSTRIDE(dst_stride);
            if (n_lines == 3) {
                pixel_copy(dst, &dst[-PXSTRIDE(dst_stride)], dst_w);
                dst += PXSTRIDE(dst_stride);
            }
        }
    } else {
        while (row + stripe_h <= row_h) {
            const int n_lines = 4 - (row + stripe_h + 1 == h);
            for (int i = 0; i < 4; i++) {
                pixel_copy(dst, i == n_lines ? &dst[-PXSTRIDE(dst_stride)] :
                                               src, src_w);
                dst += PXSTRIDE(dst_stride);
                src += PXSTRIDE(src_stride);
            }
            row += stripe_h; // unmodified stripe_h for the 1st stripe
            stripe_h = 64 >> ss_ver;
            src += (stripe_h - 4) * PXSTRIDE(src_stride);
        }
    }
}

void bytefn(dav1d_copy_lpf)(Dav1dFrameContext *const f,
                            /*const*/ pixel *const src[3], const int sby)
{
    const int have_tt = f->c->n_tc > 1;
    const int resize = f->frame_hdr->width[0] != f->frame_hdr->width[1];
    const int offset = 8 * !!sby;
    const ptrdiff_t *const src_stride = f->cur.stride;
    const ptrdiff_t *const lr_stride = f->sr_cur.p.stride;
    const int tt_off = have_tt * sby * (4 << f->seq_hdr->sb128);
    pixel *const dst[3] = {
        f->lf.lr_lpf_line[0] + tt_off * PXSTRIDE(lr_stride[0]),
        f->lf.lr_lpf_line[1] + tt_off * PXSTRIDE(lr_stride[1]),
        f->lf.lr_lpf_line[2] + tt_off * PXSTRIDE(lr_stride[1])
    };

    // TODO Also check block level restore type to reduce copying.
    const int restore_planes = f->lf.restore_planes;

    if (f->seq_hdr->cdef || restore_planes & LR_RESTORE_Y) {
        const int h = f->cur.p.h;
        const int w = f->bw << 2;
        const int row_h = imin((sby + 1) << (6 + f->seq_hdr->sb128), h - 1);
        const int y_stripe = (sby << (6 + f->seq_hdr->sb128)) - offset;
        if (restore_planes & LR_RESTORE_Y || !resize)
            backup_lpf(f, dst[0], lr_stride[0],
                       src[0] - offset * PXSTRIDE(src_stride[0]), src_stride[0],
                       0, f->seq_hdr->sb128, y_stripe, row_h, w, h, 0, 1);
        if (have_tt && resize) {
            const ptrdiff_t cdef_off_y = sby * 4 * PXSTRIDE(src_stride[0]);
            backup_lpf(f, f->lf.cdef_lpf_line[0] + cdef_off_y, src_stride[0],
                       src[0] - offset * PXSTRIDE(src_stride[0]), src_stride[0],
                       0, f->seq_hdr->sb128, y_stripe, row_h, w, h, 0, 0);
        }
    }
    if ((f->seq_hdr->cdef || restore_planes & (LR_RESTORE_U | LR_RESTORE_V)) &&
        f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400)
    {
        const int ss_ver = f->sr_cur.p.p.layout == DAV1D_PIXEL_LAYOUT_I420;
        const int ss_hor = f->sr_cur.p.p.layout != DAV1D_PIXEL_LAYOUT_I444;
        const int h = (f->cur.p.h + ss_ver) >> ss_ver;
        const int w = f->bw << (2 - ss_hor);
        const int row_h = imin((sby + 1) << ((6 - ss_ver) + f->seq_hdr->sb128), h - 1);
        const int offset_uv = offset >> ss_ver;
        const int y_stripe = (sby << ((6 - ss_ver) + f->seq_hdr->sb128)) - offset_uv;
        const ptrdiff_t cdef_off_uv = sby * 4 * PXSTRIDE(src_stride[1]);
        if (f->seq_hdr->cdef || restore_planes & LR_RESTORE_U) {
            if (restore_planes & LR_RESTORE_U || !resize)
                backup_lpf(f, dst[1], lr_stride[1],
                           src[1] - offset_uv * PXSTRIDE(src_stride[1]),
                           src_stride[1], ss_ver, f->seq_hdr->sb128, y_stripe,
                           row_h, w, h, ss_hor, 1);
            if (have_tt && resize)
                backup_lpf(f, f->lf.cdef_lpf_line[1] + cdef_off_uv, src_stride[1],
                           src[1] - offset_uv * PXSTRIDE(src_stride[1]),
                           src_stride[1], ss_ver, f->seq_hdr->sb128, y_stripe,
                           row_h, w, h, ss_hor, 0);
        }
        if (f->seq_hdr->cdef || restore_planes & LR_RESTORE_V) {
            if (restore_planes & LR_RESTORE_V || !resize)
                backup_lpf(f, dst[2], lr_stride[1],
                           src[2] - offset_uv * PXSTRIDE(src_stride[1]),
                           src_stride[1], ss_ver, f->seq_hdr->sb128, y_stripe,
                           row_h, w, h, ss_hor, 1);
            if (have_tt && resize)
                backup_lpf(f, f->lf.cdef_lpf_line[2] + cdef_off_uv, src_stride[1],
                           src[2] - offset_uv * PXSTRIDE(src_stride[1]),
                           src_stride[1], ss_ver, f->seq_hdr->sb128, y_stripe,
                           row_h, w, h, ss_hor, 0);
        }
    }
}

static inline void filter_plane_cols_y(const Dav1dFrameContext *const f,
                                       const int have_left,
                                       const uint8_t (*lvl)[4],
                                       const ptrdiff_t b4_stride,
                                       const uint16_t (*const mask)[3][2],
                                       pixel *dst, const ptrdiff_t ls,
                                       const int w,
                                       const int starty4, const int endy4)
{
    const Dav1dDSPContext *const dsp = f->dsp;

    // filter edges between columns (e.g. block1 | block2)
    for (int x = 0; x < w; x++) {
        if (!have_left && !x) continue;
        uint32_t hmask[4];
        if (!starty4) {
            hmask[0] = mask[x][0][0];
            hmask[1] = mask[x][1][0];
            hmask[2] = mask[x][2][0];
            if (endy4 > 16) {
                hmask[0] |= (unsigned) mask[x][0][1] << 16;
                hmask[1] |= (unsigned) mask[x][1][1] << 16;
                hmask[2] |= (unsigned) mask[x][2][1] << 16;
            }
        } else {
            hmask[0] = mask[x][0][1];
            hmask[1] = mask[x][1][1];
            hmask[2] = mask[x][2][1];
        }
        hmask[3] = 0;
        dsp->lf.loop_filter_sb[0][0](&dst[x * 4], ls, hmask,
                                     (const uint8_t(*)[4]) &lvl[x][0], b4_stride,
                                     &f->lf.lim_lut, endy4 - starty4 HIGHBD_CALL_SUFFIX);
    }
}

static inline void filter_plane_rows_y(const Dav1dFrameContext *const f,
                                       const int have_top,
                                       const uint8_t (*lvl)[4],
                                       const ptrdiff_t b4_stride,
                                       const uint16_t (*const mask)[3][2],
                                       pixel *dst, const ptrdiff_t ls,
                                       const int w,
                                       const int starty4, const int endy4)
{
    const Dav1dDSPContext *const dsp = f->dsp;

    //                                 block1
    // filter edges between rows (e.g. ------)
    //                                 block2
    for (int y = starty4; y < endy4;
         y++, dst += 4 * PXSTRIDE(ls), lvl += b4_stride)
    {
        if (!have_top && !y) continue;
        const uint32_t vmask[4] = {
            mask[y][0][0] | ((unsigned) mask[y][0][1] << 16),
            mask[y][1][0] | ((unsigned) mask[y][1][1] << 16),
            mask[y][2][0] | ((unsigned) mask[y][2][1] << 16),
            0,
        };
        dsp->lf.loop_filter_sb[0][1](dst, ls, vmask,
                                     (const uint8_t(*)[4]) &lvl[0][1], b4_stride,
                                     &f->lf.lim_lut, w HIGHBD_CALL_SUFFIX);
    }
}

static inline void filter_plane_cols_uv(const Dav1dFrameContext *const f,
                                        const int have_left,
                                        const uint8_t (*lvl)[4],
                                        const ptrdiff_t b4_stride,
                                        const uint16_t (*const mask)[2][2],
                                        pixel *const u, pixel *const v,
                                        const ptrdiff_t ls, const int w,
                                        const int starty4, const int endy4,
                                        const int ss_ver)
{
    const Dav1dDSPContext *const dsp = f->dsp;

    // filter edges between columns (e.g. block1 | block2)
    for (int x = 0; x < w; x++) {
        if (!have_left && !x) continue;
        uint32_t hmask[3];
        if (!starty4) {
            hmask[0] = mask[x][0][0];
            hmask[1] = mask[x][1][0];
            if (endy4 > (16 >> ss_ver)) {
                hmask[0] |= (unsigned) mask[x][0][1] << (16 >> ss_ver);
                hmask[1] |= (unsigned) mask[x][1][1] << (16 >> ss_ver);
            }
        } else {
            hmask[0] = mask[x][0][1];
            hmask[1] = mask[x][1][1];
        }
        hmask[2] = 0;
        dsp->lf.loop_filter_sb[1][0](&u[x * 4], ls, hmask,
                                     (const uint8_t(*)[4]) &lvl[x][2], b4_stride,
                                     &f->lf.lim_lut, endy4 - starty4 HIGHBD_CALL_SUFFIX);
        dsp->lf.loop_filter_sb[1][0](&v[x * 4], ls, hmask,
                                     (const uint8_t(*)[4]) &lvl[x][3], b4_stride,
                                     &f->lf.lim_lut, endy4 - starty4 HIGHBD_CALL_SUFFIX);
    }
}

static inline void filter_plane_rows_uv(const Dav1dFrameContext *const f,
                                        const int have_top,
                                        const uint8_t (*lvl)[4],
                                        const ptrdiff_t b4_stride,
                                        const uint16_t (*const mask)[2][2],
                                        pixel *const u, pixel *const v,
                                        const ptrdiff_t ls, const int w,
                                        const int starty4, const int endy4,
                                        const int ss_hor)
{
    const Dav1dDSPContext *const dsp = f->dsp;
    ptrdiff_t off_l = 0;

    //                                 block1
    // filter edges between rows (e.g. ------)
    //                                 block2
    for (int y = starty4; y < endy4;
         y++, off_l += 4 * PXSTRIDE(ls), lvl += b4_stride)
    {
        if (!have_top && !y) continue;
        const uint32_t vmask[3] = {
            mask[y][0][0] | ((unsigned) mask[y][0][1] << (16 >> ss_hor)),
            mask[y][1][0] | ((unsigned) mask[y][1][1] << (16 >> ss_hor)),
            0,
        };
        dsp->lf.loop_filter_sb[1][1](&u[off_l], ls, vmask,
                                     (const uint8_t(*)[4]) &lvl[0][2], b4_stride,
                                     &f->lf.lim_lut, w HIGHBD_CALL_SUFFIX);
        dsp->lf.loop_filter_sb[1][1](&v[off_l], ls, vmask,
                                     (const uint8_t(*)[4]) &lvl[0][3], b4_stride,
                                     &f->lf.lim_lut, w HIGHBD_CALL_SUFFIX);
    }
}

void bytefn(dav1d_loopfilter_sbrow_cols)(const Dav1dFrameContext *const f,
                                         pixel *const p[3], Av1Filter *const lflvl,
                                         int sby, const int start_of_tile_row)
{
    int x, have_left;
    // Don't filter outside the frame
    const int is_sb64 = !f->seq_hdr->sb128;
    const int starty4 = (sby & is_sb64) << 4;
    const int sbsz = 32 >> is_sb64;
    const int sbl2 = 5 - is_sb64;
    const int halign = (f->bh + 31) & ~31;
    const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
    const int ss_hor = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
    const int vmask = 16 >> ss_ver, hmask = 16 >> ss_hor;
    const unsigned vmax = 1U << vmask, hmax = 1U << hmask;
    const unsigned endy4 = starty4 + imin(f->h4 - sby * sbsz, sbsz);
    const unsigned uv_endy4 = (endy4 + ss_ver) >> ss_ver;

    // fix lpf strength at tile col boundaries
    const uint8_t *lpf_y = &f->lf.tx_lpf_right_edge[0][sby << sbl2];
    const uint8_t *lpf_uv = &f->lf.tx_lpf_right_edge[1][sby << (sbl2 - ss_ver)];
    for (int tile_col = 1;; tile_col++) {
        x = f->frame_hdr->tiling.col_start_sb[tile_col];
        if ((x << sbl2) >= f->bw) break;
        const int bx4 = x & is_sb64 ? 16 : 0, cbx4 = bx4 >> ss_hor;
        x >>= is_sb64;

        uint16_t (*const y_hmask)[2] = lflvl[x].filter_y[0][bx4];
        for (unsigned y = starty4, mask = 1 << y; y < endy4; y++, mask <<= 1) {
            const int sidx = mask >= 0x10000U;
            const unsigned smask = mask >> (sidx << 4);
            const int idx = 2 * !!(y_hmask[2][sidx] & smask) +
                                !!(y_hmask[1][sidx] & smask);
            y_hmask[2][sidx] &= ~smask;
            y_hmask[1][sidx] &= ~smask;
            y_hmask[0][sidx] &= ~smask;
            y_hmask[imin(idx, lpf_y[y - starty4])][sidx] |= smask;
        }

        if (f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400) {
            uint16_t (*const uv_hmask)[2] = lflvl[x].filter_uv[0][cbx4];
            for (unsigned y = starty4 >> ss_ver, uv_mask = 1 << y; y < uv_endy4;
                 y++, uv_mask <<= 1)
            {
                const int sidx = uv_mask >= vmax;
                const unsigned smask = uv_mask >> (sidx << (4 - ss_ver));
                const int idx = !!(uv_hmask[1][sidx] & smask);
                uv_hmask[1][sidx] &= ~smask;
                uv_hmask[0][sidx] &= ~smask;
                uv_hmask[imin(idx, lpf_uv[y - (starty4 >> ss_ver)])][sidx] |= smask;
            }
        }
        lpf_y  += halign;
        lpf_uv += halign >> ss_ver;
    }

    // fix lpf strength at tile row boundaries
    if (start_of_tile_row) {
        const BlockContext *a;
        for (x = 0, a = &f->a[f->sb128w * (start_of_tile_row - 1)];
             x < f->sb128w; x++, a++)
        {
            uint16_t (*const y_vmask)[2] = lflvl[x].filter_y[1][starty4];
            const unsigned w = imin(32, f->w4 - (x << 5));
            for (unsigned mask = 1, i = 0; i < w; mask <<= 1, i++) {
                const int sidx = mask >= 0x10000U;
                const unsigned smask = mask >> (sidx << 4);
                const int idx = 2 * !!(y_vmask[2][sidx] & smask) +
                                    !!(y_vmask[1][sidx] & smask);
                y_vmask[2][sidx] &= ~smask;
                y_vmask[1][sidx] &= ~smask;
                y_vmask[0][sidx] &= ~smask;
                y_vmask[imin(idx, a->tx_lpf_y[i])][sidx] |= smask;
            }

            if (f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I400) {
                const unsigned cw = (w + ss_hor) >> ss_hor;
                uint16_t (*const uv_vmask)[2] = lflvl[x].filter_uv[1][starty4 >> ss_ver];
                for (unsigned uv_mask = 1, i = 0; i < cw; uv_mask <<= 1, i++) {
                    const int sidx = uv_mask >= hmax;
                    const unsigned smask = uv_mask >> (sidx << (4 - ss_hor));
                    const int idx = !!(uv_vmask[1][sidx] & smask);
                    uv_vmask[1][sidx] &= ~smask;
                    uv_vmask[0][sidx] &= ~smask;
                    uv_vmask[imin(idx, a->tx_lpf_uv[i])][sidx] |= smask;
                }
            }
        }
    }

    pixel *ptr;
    uint8_t (*level_ptr)[4] = f->lf.level + f->b4_stride * sby * sbsz;
    for (ptr = p[0], have_left = 0, x = 0; x < f->sb128w;
         x++, have_left = 1, ptr += 128, level_ptr += 32)
    {
        filter_plane_cols_y(f, have_left, level_ptr, f->b4_stride,
                            lflvl[x].filter_y[0], ptr, f->cur.stride[0],
                            imin(32, f->w4 - x * 32), starty4, endy4);
    }

    if (!f->frame_hdr->loopfilter.level_u && !f->frame_hdr->loopfilter.level_v)
        return;

    ptrdiff_t uv_off;
    level_ptr = f->lf.level + f->b4_stride * (sby * sbsz >> ss_ver);
    for (uv_off = 0, have_left = 0, x = 0; x < f->sb128w;
         x++, have_left = 1, uv_off += 128 >> ss_hor, level_ptr += 32 >> ss_hor)
    {
        filter_plane_cols_uv(f, have_left, level_ptr, f->b4_stride,
                             lflvl[x].filter_uv[0],
                             &p[1][uv_off], &p[2][uv_off], f->cur.stride[1],
                             (imin(32, f->w4 - x * 32) + ss_hor) >> ss_hor,
                             starty4 >> ss_ver, uv_endy4, ss_ver);
    }
}

void bytefn(dav1d_loopfilter_sbrow_rows)(const Dav1dFrameContext *const f,
                                         pixel *const p[3], Av1Filter *const lflvl,
                                         int sby)
{
    int x;
    // Don't filter outside the frame
    const int have_top = sby > 0;
    const int is_sb64 = !f->seq_hdr->sb128;
    const int starty4 = (sby & is_sb64) << 4;
    const int sbsz = 32 >> is_sb64;
    const int ss_ver = f->cur.p.layout == DAV1D_PIXEL_LAYOUT_I420;
    const int ss_hor = f->cur.p.layout != DAV1D_PIXEL_LAYOUT_I444;
    const unsigned endy4 = starty4 + imin(f->h4 - sby * sbsz, sbsz);
    const unsigned uv_endy4 = (endy4 + ss_ver) >> ss_ver;

    pixel *ptr;
    uint8_t (*level_ptr)[4] = f->lf.level + f->b4_stride * sby * sbsz;
    for (ptr = p[0], x = 0; x < f->sb128w; x++, ptr += 128, level_ptr += 32) {
        filter_plane_rows_y(f, have_top, level_ptr, f->b4_stride,
                            lflvl[x].filter_y[1], ptr, f->cur.stride[0],
                            imin(32, f->w4 - x * 32), starty4, endy4);
    }

    if (!f->frame_hdr->loopfilter.level_u && !f->frame_hdr->loopfilter.level_v)
        return;

    ptrdiff_t uv_off;
    level_ptr = f->lf.level + f->b4_stride * (sby * sbsz >> ss_ver);
    for (uv_off = 0, x = 0; x < f->sb128w;
         x++, uv_off += 128 >> ss_hor, level_ptr += 32 >> ss_hor)
    {
        filter_plane_rows_uv(f, have_top, level_ptr, f->b4_stride,
                             lflvl[x].filter_uv[1],
                             &p[1][uv_off], &p[2][uv_off], f->cur.stride[1],
                             (imin(32, f->w4 - x * 32) + ss_hor) >> ss_hor,
                             starty4 >> ss_ver, uv_endy4, ss_hor);
    }
}