tor-browser

vp8.c (109758B)

---

/*
* VP7/VP8 compatible video decoder
*
* Copyright (C) 2010 David Conrad
* Copyright (C) 2010 Ronald S. Bultje
* Copyright (C) 2010 Fiona Glaser
* Copyright (C) 2012 Daniel Kang
* Copyright (C) 2014 Peter Ross
*
* 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 "config_components.h"

#include "libavutil/mem.h"
#include "libavutil/mem_internal.h"

#include "avcodec.h"
#include "codec_internal.h"
#include "decode.h"
#include "hwaccel_internal.h"
#include "hwconfig.h"
#include "mathops.h"
#include "progressframe.h"
#include "libavutil/refstruct.h"
#include "thread.h"
#include "vp8.h"
#include "vp89_rac.h"
#include "vp8data.h"
#include "vpx_rac.h"

#if ARCH_ARM
#   include "arm/vp8.h"
#endif

// fixme: add 1 bit to all the calls to this?
static int vp8_rac_get_sint(VPXRangeCoder *c, int bits)
{
   int v;

   if (!vp89_rac_get(c))
       return 0;

   v = vp89_rac_get_uint(c, bits);

   if (vp89_rac_get(c))
       v = -v;

   return v;
}

static int vp8_rac_get_nn(VPXRangeCoder *c)
{
   int v = vp89_rac_get_uint(c, 7) << 1;
   return v + !v;
}

// DCTextra
static int vp8_rac_get_coeff(VPXRangeCoder *c, const uint8_t *prob)
{
   int v = 0;

   do {
       v = (v<<1) + vpx_rac_get_prob(c, *prob++);
   } while (*prob);

   return v;
}

static void free_buffers(VP8Context *s)
{
   int i;
   if (s->thread_data)
       for (i = 0; i < MAX_THREADS; i++) {
#if HAVE_THREADS
           pthread_cond_destroy(&s->thread_data[i].cond);
           pthread_mutex_destroy(&s->thread_data[i].lock);
#endif
           av_freep(&s->thread_data[i].filter_strength);
       }
   av_freep(&s->thread_data);
   av_freep(&s->macroblocks_base);
   av_freep(&s->intra4x4_pred_mode_top);
   av_freep(&s->top_nnz);
   av_freep(&s->top_border);

   s->macroblocks = NULL;
}

static int vp8_alloc_frame(VP8Context *s, VP8Frame *f, int ref)
{
   int ret = ff_progress_frame_get_buffer(s->avctx, &f->tf,
                                          ref ? AV_GET_BUFFER_FLAG_REF : 0);
   if (ret < 0)
       return ret;
   f->seg_map = av_refstruct_allocz(s->mb_width * s->mb_height);
   if (!f->seg_map) {
       ret = AVERROR(ENOMEM);
       goto fail;
   }
   ret = ff_hwaccel_frame_priv_alloc(s->avctx, &f->hwaccel_picture_private);
   if (ret < 0)
       goto fail;

   return 0;

fail:
   av_refstruct_unref(&f->seg_map);
   ff_progress_frame_unref(&f->tf);
   return ret;
}

static void vp8_release_frame(VP8Frame *f)
{
   av_refstruct_unref(&f->seg_map);
   av_refstruct_unref(&f->hwaccel_picture_private);
   ff_progress_frame_unref(&f->tf);
}

static av_cold void vp8_decode_flush_impl(AVCodecContext *avctx, int free_mem)
{
   VP8Context *s = avctx->priv_data;
   int i;

   for (i = 0; i < FF_ARRAY_ELEMS(s->frames); i++)
       vp8_release_frame(&s->frames[i]);
   memset(s->framep, 0, sizeof(s->framep));

   if (free_mem)
       free_buffers(s);

   if (FF_HW_HAS_CB(avctx, flush))
       FF_HW_SIMPLE_CALL(avctx, flush);
}

static av_cold void vp8_decode_flush(AVCodecContext *avctx)
{
   vp8_decode_flush_impl(avctx, 0);
}

static VP8Frame *vp8_find_free_buffer(VP8Context *s)
{
   VP8Frame *frame = NULL;
   int i;

   // find a free buffer
   for (i = 0; i < 5; i++)
       if (&s->frames[i] != s->framep[VP8_FRAME_CURRENT]  &&
           &s->frames[i] != s->framep[VP8_FRAME_PREVIOUS] &&
           &s->frames[i] != s->framep[VP8_FRAME_GOLDEN]   &&
           &s->frames[i] != s->framep[VP8_FRAME_ALTREF]) {
           frame = &s->frames[i];
           break;
       }
   if (i == 5) {
       av_log(s->avctx, AV_LOG_FATAL, "Ran out of free frames!\n");
       abort();
   }
   if (frame->tf.f)
       vp8_release_frame(frame);

   return frame;
}

static enum AVPixelFormat get_pixel_format(VP8Context *s)
{
   enum AVPixelFormat pix_fmts[] = {
#if CONFIG_VP8_VAAPI_HWACCEL
       AV_PIX_FMT_VAAPI,
#endif
#if CONFIG_VP8_NVDEC_HWACCEL
       AV_PIX_FMT_CUDA,
#endif
       AV_PIX_FMT_YUV420P,
       AV_PIX_FMT_NONE,
   };

   return ff_get_format(s->avctx, pix_fmts);
}

static av_always_inline
int update_dimensions(VP8Context *s, int width, int height, int is_vp7)
{
   AVCodecContext *avctx = s->avctx;
   int i, ret, dim_reset = 0;

   if (width  != s->avctx->width || ((width+15)/16 != s->mb_width || (height+15)/16 != s->mb_height) && s->macroblocks_base ||
       height != s->avctx->height) {
       vp8_decode_flush_impl(s->avctx, 1);

       ret = ff_set_dimensions(s->avctx, width, height);
       if (ret < 0)
           return ret;

       dim_reset = (s->macroblocks_base != NULL);
   }

   if ((s->pix_fmt == AV_PIX_FMT_NONE || dim_reset) &&
        !s->actually_webp && !is_vp7) {
       s->pix_fmt = get_pixel_format(s);
       if (s->pix_fmt < 0)
           return AVERROR(EINVAL);
       avctx->pix_fmt = s->pix_fmt;
   }

   s->mb_width  = (s->avctx->coded_width  + 15) / 16;
   s->mb_height = (s->avctx->coded_height + 15) / 16;

   s->mb_layout = is_vp7 || avctx->active_thread_type == FF_THREAD_SLICE &&
                  avctx->thread_count > 1;
   if (!s->mb_layout) { // Frame threading and one thread
       s->macroblocks_base       = av_mallocz((s->mb_width + s->mb_height * 2 + 1) *
                                              sizeof(*s->macroblocks));
       s->intra4x4_pred_mode_top = av_mallocz(s->mb_width * 4);
   } else // Sliced threading
       s->macroblocks_base = av_mallocz((s->mb_width + 2) * (s->mb_height + 2) *
                                        sizeof(*s->macroblocks));
   s->top_nnz     = av_mallocz(s->mb_width * sizeof(*s->top_nnz));
   s->top_border  = av_mallocz((s->mb_width + 1) * sizeof(*s->top_border));
   s->thread_data = av_mallocz(MAX_THREADS * sizeof(VP8ThreadData));

   if (!s->macroblocks_base || !s->top_nnz || !s->top_border ||
       !s->thread_data || (!s->intra4x4_pred_mode_top && !s->mb_layout)) {
       free_buffers(s);
       return AVERROR(ENOMEM);
   }

   for (i = 0; i < MAX_THREADS; i++) {
       s->thread_data[i].filter_strength =
           av_mallocz(s->mb_width * sizeof(*s->thread_data[0].filter_strength));
       if (!s->thread_data[i].filter_strength) {
           free_buffers(s);
           return AVERROR(ENOMEM);
       }
#if HAVE_THREADS
       ret = pthread_mutex_init(&s->thread_data[i].lock, NULL);
       if (ret) {
           free_buffers(s);
           return AVERROR(ret);
       }
       ret = pthread_cond_init(&s->thread_data[i].cond, NULL);
       if (ret) {
           free_buffers(s);
           return AVERROR(ret);
       }
#endif
   }

   s->macroblocks = s->macroblocks_base + 1;

   return 0;
}

static int vp7_update_dimensions(VP8Context *s, int width, int height)
{
   return update_dimensions(s, width, height, IS_VP7);
}

static int vp8_update_dimensions(VP8Context *s, int width, int height)
{
   return update_dimensions(s, width, height, IS_VP8);
}


static void parse_segment_info(VP8Context *s)
{
   VPXRangeCoder *c = &s->c;
   int i;

   s->segmentation.update_map = vp89_rac_get(c);
   s->segmentation.update_feature_data = vp89_rac_get(c);

   if (s->segmentation.update_feature_data) {
       s->segmentation.absolute_vals = vp89_rac_get(c);

       for (i = 0; i < 4; i++)
           s->segmentation.base_quant[i]   = vp8_rac_get_sint(c, 7);

       for (i = 0; i < 4; i++)
           s->segmentation.filter_level[i] = vp8_rac_get_sint(c, 6);
   }
   if (s->segmentation.update_map)
       for (i = 0; i < 3; i++)
           s->prob->segmentid[i] = vp89_rac_get(c) ? vp89_rac_get_uint(c, 8) : 255;
}

static void update_lf_deltas(VP8Context *s)
{
   VPXRangeCoder *c = &s->c;
   int i;

   for (i = 0; i < 4; i++) {
       if (vp89_rac_get(c)) {
           s->lf_delta.ref[i] = vp89_rac_get_uint(c, 6);

           if (vp89_rac_get(c))
               s->lf_delta.ref[i] = -s->lf_delta.ref[i];
       }
   }

   for (i = MODE_I4x4; i <= VP8_MVMODE_SPLIT; i++) {
       if (vp89_rac_get(c)) {
           s->lf_delta.mode[i] = vp89_rac_get_uint(c, 6);

           if (vp89_rac_get(c))
               s->lf_delta.mode[i] = -s->lf_delta.mode[i];
       }
   }
}

static int setup_partitions(VP8Context *s, const uint8_t *buf, int buf_size)
{
   const uint8_t *sizes = buf;
   int i;
   int ret;

   s->num_coeff_partitions = 1 << vp89_rac_get_uint(&s->c, 2);

   buf      += 3 * (s->num_coeff_partitions - 1);
   buf_size -= 3 * (s->num_coeff_partitions - 1);
   if (buf_size < 0)
       return -1;

   for (i = 0; i < s->num_coeff_partitions - 1; i++) {
       int size = AV_RL24(sizes + 3 * i);
       if (buf_size - size < 0)
           return -1;
       s->coeff_partition_size[i] = size;

       ret = ff_vpx_init_range_decoder(&s->coeff_partition[i], buf, size);
       if (ret < 0)
           return ret;
       buf      += size;
       buf_size -= size;
   }

   s->coeff_partition_size[i] = buf_size;

   return ff_vpx_init_range_decoder(&s->coeff_partition[i], buf, buf_size);
}

static void vp7_get_quants(VP8Context *s)
{
   VPXRangeCoder *c = &s->c;

   int yac_qi  = vp89_rac_get_uint(c, 7);
   int ydc_qi  = vp89_rac_get(c) ? vp89_rac_get_uint(c, 7) : yac_qi;
   int y2dc_qi = vp89_rac_get(c) ? vp89_rac_get_uint(c, 7) : yac_qi;
   int y2ac_qi = vp89_rac_get(c) ? vp89_rac_get_uint(c, 7) : yac_qi;
   int uvdc_qi = vp89_rac_get(c) ? vp89_rac_get_uint(c, 7) : yac_qi;
   int uvac_qi = vp89_rac_get(c) ? vp89_rac_get_uint(c, 7) : yac_qi;

   s->qmat[0].luma_qmul[0]    =       vp7_ydc_qlookup[ydc_qi];
   s->qmat[0].luma_qmul[1]    =       vp7_yac_qlookup[yac_qi];
   s->qmat[0].luma_dc_qmul[0] =       vp7_y2dc_qlookup[y2dc_qi];
   s->qmat[0].luma_dc_qmul[1] =       vp7_y2ac_qlookup[y2ac_qi];
   s->qmat[0].chroma_qmul[0]  = FFMIN(vp7_ydc_qlookup[uvdc_qi], 132);
   s->qmat[0].chroma_qmul[1]  =       vp7_yac_qlookup[uvac_qi];
}

static void vp8_get_quants(VP8Context *s)
{
   VPXRangeCoder *c = &s->c;
   int i, base_qi;

   s->quant.yac_qi     = vp89_rac_get_uint(c, 7);
   s->quant.ydc_delta  = vp8_rac_get_sint(c, 4);
   s->quant.y2dc_delta = vp8_rac_get_sint(c, 4);
   s->quant.y2ac_delta = vp8_rac_get_sint(c, 4);
   s->quant.uvdc_delta = vp8_rac_get_sint(c, 4);
   s->quant.uvac_delta = vp8_rac_get_sint(c, 4);

   for (i = 0; i < 4; i++) {
       if (s->segmentation.enabled) {
           base_qi = s->segmentation.base_quant[i];
           if (!s->segmentation.absolute_vals)
               base_qi += s->quant.yac_qi;
       } else
           base_qi = s->quant.yac_qi;

       s->qmat[i].luma_qmul[0]    = vp8_dc_qlookup[av_clip_uintp2(base_qi + s->quant.ydc_delta,  7)];
       s->qmat[i].luma_qmul[1]    = vp8_ac_qlookup[av_clip_uintp2(base_qi,              7)];
       s->qmat[i].luma_dc_qmul[0] = vp8_dc_qlookup[av_clip_uintp2(base_qi + s->quant.y2dc_delta, 7)] * 2;
       /* 101581>>16 is equivalent to 155/100 */
       s->qmat[i].luma_dc_qmul[1] = vp8_ac_qlookup[av_clip_uintp2(base_qi + s->quant.y2ac_delta, 7)] * 101581 >> 16;
       s->qmat[i].chroma_qmul[0]  = vp8_dc_qlookup[av_clip_uintp2(base_qi + s->quant.uvdc_delta, 7)];
       s->qmat[i].chroma_qmul[1]  = vp8_ac_qlookup[av_clip_uintp2(base_qi + s->quant.uvac_delta, 7)];

       s->qmat[i].luma_dc_qmul[1] = FFMAX(s->qmat[i].luma_dc_qmul[1], 8);
       s->qmat[i].chroma_qmul[0]  = FFMIN(s->qmat[i].chroma_qmul[0], 132);
   }
}

/**
* Determine which buffers golden and altref should be updated with after this frame.
* The spec isn't clear here, so I'm going by my understanding of what libvpx does
*
* Intra frames update all 3 references
* Inter frames update VP8_FRAME_PREVIOUS if the update_last flag is set
* If the update (golden|altref) flag is set, it's updated with the current frame
*      if update_last is set, and VP8_FRAME_PREVIOUS otherwise.
* If the flag is not set, the number read means:
*      0: no update
*      1: VP8_FRAME_PREVIOUS
*      2: update golden with altref, or update altref with golden
*/
static VP8FrameType ref_to_update(VP8Context *s, int update, VP8FrameType ref)
{
   VPXRangeCoder *c = &s->c;

   if (update)
       return VP8_FRAME_CURRENT;

   switch (vp89_rac_get_uint(c, 2)) {
   case 1:
       return VP8_FRAME_PREVIOUS;
   case 2:
       return (ref == VP8_FRAME_GOLDEN) ? VP8_FRAME_ALTREF : VP8_FRAME_GOLDEN;
   }
   return VP8_FRAME_NONE;
}

static void vp78_reset_probability_tables(VP8Context *s)
{
   int i, j;
   for (i = 0; i < 4; i++)
       for (j = 0; j < 16; j++)
           memcpy(s->prob->token[i][j], vp8_token_default_probs[i][vp8_coeff_band[j]],
                  sizeof(s->prob->token[i][j]));
}

static void vp78_update_probability_tables(VP8Context *s)
{
   VPXRangeCoder *c = &s->c;
   int i, j, k, l, m;

   for (i = 0; i < 4; i++)
       for (j = 0; j < 8; j++)
           for (k = 0; k < 3; k++)
               for (l = 0; l < NUM_DCT_TOKENS-1; l++)
                   if (vpx_rac_get_prob_branchy(c, ff_vp8_token_update_probs[i][j][k][l])) {
                       int prob = vp89_rac_get_uint(c, 8);
                       for (m = 0; vp8_coeff_band_indexes[j][m] >= 0; m++)
                           s->prob->token[i][vp8_coeff_band_indexes[j][m]][k][l] = prob;
                   }
}

#define VP7_MVC_SIZE 17
#define VP8_MVC_SIZE 19

static void vp78_update_pred16x16_pred8x8_mvc_probabilities(VP8Context *s,
                                                           int mvc_size)
{
   VPXRangeCoder *c = &s->c;
   int i, j;

   if (vp89_rac_get(c))
       for (i = 0; i < 4; i++)
           s->prob->pred16x16[i] = vp89_rac_get_uint(c, 8);
   if (vp89_rac_get(c))
       for (i = 0; i < 3; i++)
           s->prob->pred8x8c[i]  = vp89_rac_get_uint(c, 8);

   // 17.2 MV probability update
   for (i = 0; i < 2; i++)
       for (j = 0; j < mvc_size; j++)
           if (vpx_rac_get_prob_branchy(c, vp8_mv_update_prob[i][j]))
               s->prob->mvc[i][j] = vp8_rac_get_nn(c);
}

static void update_refs(VP8Context *s)
{
   VPXRangeCoder *c = &s->c;

   int update_golden = vp89_rac_get(c);
   int update_altref = vp89_rac_get(c);

   s->update_golden = ref_to_update(s, update_golden, VP8_FRAME_GOLDEN);
   s->update_altref = ref_to_update(s, update_altref, VP8_FRAME_ALTREF);
}

static void copy_chroma(AVFrame *dst, const AVFrame *src, int width, int height)
{
   int i, j;

   for (j = 1; j < 3; j++) {
       for (i = 0; i < height / 2; i++)
           memcpy(dst->data[j] + i * dst->linesize[j],
                  src->data[j] + i * src->linesize[j], width / 2);
   }
}

static void fade(uint8_t *dst, ptrdiff_t dst_linesize,
                const uint8_t *src, ptrdiff_t src_linesize,
                int width, int height,
                int alpha, int beta)
{
   int i, j;
   for (j = 0; j < height; j++) {
       const uint8_t *src2 = src + j * src_linesize;
       uint8_t *dst2 = dst + j * dst_linesize;
       for (i = 0; i < width; i++) {
           uint8_t y = src2[i];
           dst2[i] = av_clip_uint8(y + ((y * beta) >> 8) + alpha);
       }
   }
}

static int vp7_fade_frame(VP8Context *s, int alpha, int beta)
{
   int ret;

   if (!s->keyframe && (alpha || beta)) {
       int width  = s->mb_width * 16;
       int height = s->mb_height * 16;
       const AVFrame *src;
       AVFrame *dst;

       if (!s->framep[VP8_FRAME_PREVIOUS] ||
           !s->framep[VP8_FRAME_GOLDEN]) {
           av_log(s->avctx, AV_LOG_WARNING, "Discarding interframe without a prior keyframe!\n");
           return AVERROR_INVALIDDATA;
       }

       src =
       dst = s->framep[VP8_FRAME_PREVIOUS]->tf.f;

       /* preserve the golden frame, write a new previous frame */
       if (s->framep[VP8_FRAME_GOLDEN] == s->framep[VP8_FRAME_PREVIOUS]) {
           s->framep[VP8_FRAME_PREVIOUS] = vp8_find_free_buffer(s);
           if ((ret = vp8_alloc_frame(s, s->framep[VP8_FRAME_PREVIOUS], 1)) < 0)
               return ret;

           dst = s->framep[VP8_FRAME_PREVIOUS]->tf.f;

           copy_chroma(dst, src, width, height);
       }

       fade(dst->data[0], dst->linesize[0],
            src->data[0], src->linesize[0],
            width, height, alpha, beta);
   }

   return 0;
}

static int vp7_decode_frame_header(VP8Context *s, const uint8_t *buf, int buf_size)
{
   VPXRangeCoder *c = &s->c;
   int part1_size, hscale, vscale, i, j, ret;
   int width  = s->avctx->width;
   int height = s->avctx->height;
   int alpha = 0;
   int beta  = 0;
   int fade_present = 1;

   if (buf_size < 4) {
       return AVERROR_INVALIDDATA;
   }

   s->profile = (buf[0] >> 1) & 7;
   if (s->profile > 1) {
       avpriv_request_sample(s->avctx, "Unknown profile %d", s->profile);
       return AVERROR_INVALIDDATA;
   }

   s->keyframe  = !(buf[0] & 1);
   s->invisible = 0;
   part1_size   = AV_RL24(buf) >> 4;

   if (buf_size < 4 - s->profile + part1_size) {
       av_log(s->avctx, AV_LOG_ERROR, "Buffer size %d is too small, needed : %d\n", buf_size, 4 - s->profile + part1_size);
       return AVERROR_INVALIDDATA;
   }

   buf      += 4 - s->profile;
   buf_size -= 4 - s->profile;

   memcpy(s->put_pixels_tab, s->vp8dsp.put_vp8_epel_pixels_tab, sizeof(s->put_pixels_tab));

   ret = ff_vpx_init_range_decoder(c, buf, part1_size);
   if (ret < 0)
       return ret;
   buf      += part1_size;
   buf_size -= part1_size;

   /* A. Dimension information (keyframes only) */
   if (s->keyframe) {
       width  = vp89_rac_get_uint(c, 12);
       height = vp89_rac_get_uint(c, 12);
       hscale = vp89_rac_get_uint(c, 2);
       vscale = vp89_rac_get_uint(c, 2);
       if (hscale || vscale)
           avpriv_request_sample(s->avctx, "Upscaling");

       s->update_golden = s->update_altref = VP8_FRAME_CURRENT;
       vp78_reset_probability_tables(s);
       memcpy(s->prob->pred16x16, vp8_pred16x16_prob_inter,
              sizeof(s->prob->pred16x16));
       memcpy(s->prob->pred8x8c, vp8_pred8x8c_prob_inter,
              sizeof(s->prob->pred8x8c));
       for (i = 0; i < 2; i++)
           memcpy(s->prob->mvc[i], vp7_mv_default_prob[i],
                  sizeof(vp7_mv_default_prob[i]));
       memset(&s->segmentation, 0, sizeof(s->segmentation));
       memset(&s->lf_delta, 0, sizeof(s->lf_delta));
       memcpy(s->prob[0].scan, ff_zigzag_scan, sizeof(s->prob[0].scan));
   }

   if (s->keyframe || s->profile > 0)
       memset(s->inter_dc_pred, 0 , sizeof(s->inter_dc_pred));

   /* B. Decoding information for all four macroblock-level features */
   for (i = 0; i < 4; i++) {
       s->feature_enabled[i] = vp89_rac_get(c);
       if (s->feature_enabled[i]) {
            s->feature_present_prob[i] = vp89_rac_get_uint(c, 8);

            for (j = 0; j < 3; j++)
                s->feature_index_prob[i][j] =
                    vp89_rac_get(c) ? vp89_rac_get_uint(c, 8) : 255;

            if (vp7_feature_value_size[s->profile][i])
                for (j = 0; j < 4; j++)
                    s->feature_value[i][j] =
                       vp89_rac_get(c) ? vp89_rac_get_uint(c, vp7_feature_value_size[s->profile][i]) : 0;
       }
   }

   s->segmentation.enabled    = 0;
   s->segmentation.update_map = 0;
   s->lf_delta.enabled        = 0;

   s->num_coeff_partitions = 1;
   ret = ff_vpx_init_range_decoder(&s->coeff_partition[0], buf, buf_size);
   if (ret < 0)
       return ret;

   if (!s->macroblocks_base || /* first frame */
       width != s->avctx->width || height != s->avctx->height ||
       (width + 15) / 16 != s->mb_width || (height + 15) / 16 != s->mb_height) {
       if ((ret = vp7_update_dimensions(s, width, height)) < 0)
           return ret;
   }

   /* C. Dequantization indices */
   vp7_get_quants(s);

   /* D. Golden frame update flag (a Flag) for interframes only */
   if (!s->keyframe) {
       s->update_golden = vp89_rac_get(c) ? VP8_FRAME_CURRENT : VP8_FRAME_NONE;
       s->sign_bias[VP8_FRAME_GOLDEN] = 0;
   }

   s->update_last          = 1;
   s->update_probabilities = 1;

   if (s->profile > 0) {
       s->update_probabilities = vp89_rac_get(c);
       if (!s->update_probabilities)
           s->prob[1] = s->prob[0];

       if (!s->keyframe)
           fade_present = vp89_rac_get(c);
   }

   if (vpx_rac_is_end(c))
       return AVERROR_INVALIDDATA;
   /* E. Fading information for previous frame */
   if (fade_present && vp89_rac_get(c)) {
       alpha = (int8_t) vp89_rac_get_uint(c, 8);
       beta  = (int8_t) vp89_rac_get_uint(c, 8);
   }

   /* F. Loop filter type */
   if (!s->profile)
       s->filter.simple = vp89_rac_get(c);

   /* G. DCT coefficient ordering specification */
   if (vp89_rac_get(c))
       for (i = 1; i < 16; i++)
           s->prob[0].scan[i] = ff_zigzag_scan[vp89_rac_get_uint(c, 4)];

   /* H. Loop filter levels  */
   if (s->profile > 0)
       s->filter.simple = vp89_rac_get(c);
   s->filter.level     = vp89_rac_get_uint(c, 6);
   s->filter.sharpness = vp89_rac_get_uint(c, 3);

   /* I. DCT coefficient probability update; 13.3 Token Probability Updates */
   vp78_update_probability_tables(s);

   s->mbskip_enabled = 0;

   /* J. The remaining frame header data occurs ONLY FOR INTERFRAMES */
   if (!s->keyframe) {
       s->prob->intra  = vp89_rac_get_uint(c, 8);
       s->prob->last   = vp89_rac_get_uint(c, 8);
       vp78_update_pred16x16_pred8x8_mvc_probabilities(s, VP7_MVC_SIZE);
   }

   if (vpx_rac_is_end(c))
       return AVERROR_INVALIDDATA;

   if ((ret = vp7_fade_frame(s, alpha, beta)) < 0)
       return ret;

   return 0;
}

static int vp8_decode_frame_header(VP8Context *s, const uint8_t *buf, int buf_size)
{
   VPXRangeCoder *c = &s->c;
   int header_size, hscale, vscale, ret;
   int width  = s->avctx->width;
   int height = s->avctx->height;

   if (buf_size < 3) {
       av_log(s->avctx, AV_LOG_ERROR, "Insufficent data (%d) for header\n", buf_size);
       return AVERROR_INVALIDDATA;
   }

   s->keyframe  = !(buf[0] & 1);
   s->profile   =  (buf[0]>>1) & 7;
   s->invisible = !(buf[0] & 0x10);
   header_size  = AV_RL24(buf) >> 5;
   buf      += 3;
   buf_size -= 3;

   s->header_partition_size = header_size;

   if (s->profile > 3)
       av_log(s->avctx, AV_LOG_WARNING, "Unknown profile %d\n", s->profile);

   if (!s->profile)
       memcpy(s->put_pixels_tab, s->vp8dsp.put_vp8_epel_pixels_tab,
              sizeof(s->put_pixels_tab));
   else    // profile 1-3 use bilinear, 4+ aren't defined so whatever
       memcpy(s->put_pixels_tab, s->vp8dsp.put_vp8_bilinear_pixels_tab,
              sizeof(s->put_pixels_tab));

   if (header_size > buf_size - 7 * s->keyframe) {
       av_log(s->avctx, AV_LOG_ERROR, "Header size larger than data provided\n");
       return AVERROR_INVALIDDATA;
   }

   if (s->keyframe) {
       if (AV_RL24(buf) != 0x2a019d) {
           av_log(s->avctx, AV_LOG_ERROR,
                  "Invalid start code 0x%x\n", AV_RL24(buf));
           return AVERROR_INVALIDDATA;
       }
       width     = AV_RL16(buf + 3) & 0x3fff;
       height    = AV_RL16(buf + 5) & 0x3fff;
       hscale    = buf[4] >> 6;
       vscale    = buf[6] >> 6;
       buf      += 7;
       buf_size -= 7;

       if (hscale || vscale)
           avpriv_request_sample(s->avctx, "Upscaling");

       s->update_golden = s->update_altref = VP8_FRAME_CURRENT;
       vp78_reset_probability_tables(s);
       memcpy(s->prob->pred16x16, vp8_pred16x16_prob_inter,
              sizeof(s->prob->pred16x16));
       memcpy(s->prob->pred8x8c, vp8_pred8x8c_prob_inter,
              sizeof(s->prob->pred8x8c));
       memcpy(s->prob->mvc, vp8_mv_default_prob,
              sizeof(s->prob->mvc));
       memset(&s->segmentation, 0, sizeof(s->segmentation));
       memset(&s->lf_delta, 0, sizeof(s->lf_delta));
   }

   ret = ff_vpx_init_range_decoder(c, buf, header_size);
   if (ret < 0)
       return ret;
   buf      += header_size;
   buf_size -= header_size;

   if (s->keyframe) {
       s->colorspace = vp89_rac_get(c);
       if (s->colorspace)
           av_log(s->avctx, AV_LOG_WARNING, "Unspecified colorspace\n");
       s->fullrange = vp89_rac_get(c);
   }

   if ((s->segmentation.enabled = vp89_rac_get(c)))
       parse_segment_info(s);
   else
       s->segmentation.update_map = 0; // FIXME: move this to some init function?

   s->filter.simple    = vp89_rac_get(c);
   s->filter.level     = vp89_rac_get_uint(c, 6);
   s->filter.sharpness = vp89_rac_get_uint(c, 3);

   if ((s->lf_delta.enabled = vp89_rac_get(c))) {
       s->lf_delta.update = vp89_rac_get(c);
       if (s->lf_delta.update)
           update_lf_deltas(s);
   }

   if (setup_partitions(s, buf, buf_size)) {
       av_log(s->avctx, AV_LOG_ERROR, "Invalid partitions\n");
       return AVERROR_INVALIDDATA;
   }

   if (!s->macroblocks_base || /* first frame */
       width != s->avctx->width || height != s->avctx->height ||
       (width+15)/16 != s->mb_width || (height+15)/16 != s->mb_height)
       if ((ret = vp8_update_dimensions(s, width, height)) < 0)
           return ret;

   vp8_get_quants(s);

   if (!s->keyframe) {
       update_refs(s);
       s->sign_bias[VP8_FRAME_GOLDEN] = vp89_rac_get(c);
       s->sign_bias[VP8_FRAME_ALTREF] = vp89_rac_get(c);
   }

   // if we aren't saving this frame's probabilities for future frames,
   // make a copy of the current probabilities
   if (!(s->update_probabilities = vp89_rac_get(c)))
       s->prob[1] = s->prob[0];

   s->update_last = s->keyframe || vp89_rac_get(c);

   vp78_update_probability_tables(s);

   if ((s->mbskip_enabled = vp89_rac_get(c)))
       s->prob->mbskip = vp89_rac_get_uint(c, 8);

   if (!s->keyframe) {
       s->prob->intra  = vp89_rac_get_uint(c, 8);
       s->prob->last   = vp89_rac_get_uint(c, 8);
       s->prob->golden = vp89_rac_get_uint(c, 8);
       vp78_update_pred16x16_pred8x8_mvc_probabilities(s, VP8_MVC_SIZE);
   }

   // Record the entropy coder state here so that hwaccels can use it.
   s->c.code_word = vpx_rac_renorm(&s->c);
   s->coder_state_at_header_end.input     = s->c.buffer - (-s->c.bits / 8);
   s->coder_state_at_header_end.range     = s->c.high;
   s->coder_state_at_header_end.value     = s->c.code_word >> 16;
   s->coder_state_at_header_end.bit_count = -s->c.bits % 8;

   return 0;
}

static av_always_inline
void clamp_mv(const VP8mvbounds *s, VP8mv *dst, const VP8mv *src)
{
   dst->x = av_clip(src->x, av_clip(s->mv_min.x, INT16_MIN, INT16_MAX),
                            av_clip(s->mv_max.x, INT16_MIN, INT16_MAX));
   dst->y = av_clip(src->y, av_clip(s->mv_min.y, INT16_MIN, INT16_MAX),
                            av_clip(s->mv_max.y, INT16_MIN, INT16_MAX));
}

/**
* Motion vector coding, 17.1.
*/
static av_always_inline int read_mv_component(VPXRangeCoder *c, const uint8_t *p, int vp7)
{
   int bit, x = 0;

   if (vpx_rac_get_prob_branchy(c, p[0])) {
       int i;

       for (i = 0; i < 3; i++)
           x += vpx_rac_get_prob(c, p[9 + i]) << i;
       for (i = (vp7 ? 7 : 9); i > 3; i--)
           x += vpx_rac_get_prob(c, p[9 + i]) << i;
       if (!(x & (vp7 ? 0xF0 : 0xFFF0)) || vpx_rac_get_prob(c, p[12]))
           x += 8;
   } else {
       // small_mvtree
       const uint8_t *ps = p + 2;
       bit = vpx_rac_get_prob(c, *ps);
       ps += 1 + 3 * bit;
       x  += 4 * bit;
       bit = vpx_rac_get_prob(c, *ps);
       ps += 1 + bit;
       x  += 2 * bit;
       x  += vpx_rac_get_prob(c, *ps);
   }

   return (x && vpx_rac_get_prob(c, p[1])) ? -x : x;
}

static int vp7_read_mv_component(VPXRangeCoder *c, const uint8_t *p)
{
   return read_mv_component(c, p, 1);
}

static int vp8_read_mv_component(VPXRangeCoder *c, const uint8_t *p)
{
   return read_mv_component(c, p, 0);
}

static av_always_inline
const uint8_t *get_submv_prob(uint32_t left, uint32_t top, int is_vp7)
{
   if (is_vp7)
       return vp7_submv_prob;

   if (left == top)
       return vp8_submv_prob[4 - !!left];
   if (!top)
       return vp8_submv_prob[2];
   return vp8_submv_prob[1 - !!left];
}

/**
* Split motion vector prediction, 16.4.
* @returns the number of motion vectors parsed (2, 4 or 16)
*/
static av_always_inline
int decode_splitmvs(const VP8Context *s, VPXRangeCoder *c, VP8Macroblock *mb,
                   int layout, int is_vp7)
{
   int part_idx;
   int n, num;
   const VP8Macroblock *top_mb;
   const VP8Macroblock *left_mb = &mb[-1];
   const uint8_t *mbsplits_left = vp8_mbsplits[left_mb->partitioning];
   const uint8_t *mbsplits_top, *mbsplits_cur, *firstidx;
   const VP8mv *top_mv;
   const VP8mv *left_mv = left_mb->bmv;
   const VP8mv *cur_mv  = mb->bmv;

   if (!layout) // layout is inlined, s->mb_layout is not
       top_mb = &mb[2];
   else
       top_mb = &mb[-s->mb_width - 1];
   mbsplits_top = vp8_mbsplits[top_mb->partitioning];
   top_mv       = top_mb->bmv;

   if (vpx_rac_get_prob_branchy(c, vp8_mbsplit_prob[0])) {
       if (vpx_rac_get_prob_branchy(c, vp8_mbsplit_prob[1]))
           part_idx = VP8_SPLITMVMODE_16x8 + vpx_rac_get_prob(c, vp8_mbsplit_prob[2]);
       else
           part_idx = VP8_SPLITMVMODE_8x8;
   } else {
       part_idx = VP8_SPLITMVMODE_4x4;
   }

   num              = vp8_mbsplit_count[part_idx];
   mbsplits_cur     = vp8_mbsplits[part_idx],
   firstidx         = vp8_mbfirstidx[part_idx];
   mb->partitioning = part_idx;

   for (n = 0; n < num; n++) {
       int k = firstidx[n];
       uint32_t left, above;
       const uint8_t *submv_prob;

       if (!(k & 3))
           left = AV_RN32A(&left_mv[mbsplits_left[k + 3]]);
       else
           left = AV_RN32A(&cur_mv[mbsplits_cur[k - 1]]);
       if (k <= 3)
           above = AV_RN32A(&top_mv[mbsplits_top[k + 12]]);
       else
           above = AV_RN32A(&cur_mv[mbsplits_cur[k - 4]]);

       submv_prob = get_submv_prob(left, above, is_vp7);

       if (vpx_rac_get_prob_branchy(c, submv_prob[0])) {
           if (vpx_rac_get_prob_branchy(c, submv_prob[1])) {
               if (vpx_rac_get_prob_branchy(c, submv_prob[2])) {
                   mb->bmv[n].y = mb->mv.y +
                                  read_mv_component(c, s->prob->mvc[0], is_vp7);
                   mb->bmv[n].x = mb->mv.x +
                                  read_mv_component(c, s->prob->mvc[1], is_vp7);
               } else {
                   AV_ZERO32(&mb->bmv[n]);
               }
           } else {
               AV_WN32A(&mb->bmv[n], above);
           }
       } else {
           AV_WN32A(&mb->bmv[n], left);
       }
   }

   return num;
}

/**
* The vp7 reference decoder uses a padding macroblock column (added to right
* edge of the frame) to guard against illegal macroblock offsets. The
* algorithm has bugs that permit offsets to straddle the padding column.
* This function replicates those bugs.
*
* @param[out] edge_x macroblock x address
* @param[out] edge_y macroblock y address
*
* @return macroblock offset legal (boolean)
*/
static int vp7_calculate_mb_offset(int mb_x, int mb_y, int mb_width,
                                  int xoffset, int yoffset, int boundary,
                                  int *edge_x, int *edge_y)
{
   int vwidth = mb_width + 1;
   int new = (mb_y + yoffset) * vwidth + mb_x + xoffset;
   if (new < boundary || new % vwidth == vwidth - 1)
       return 0;
   *edge_y = new / vwidth;
   *edge_x = new % vwidth;
   return 1;
}

static const VP8mv *get_bmv_ptr(const VP8Macroblock *mb, int subblock)
{
   return &mb->bmv[mb->mode == VP8_MVMODE_SPLIT ? vp8_mbsplits[mb->partitioning][subblock] : 0];
}

static av_always_inline
void vp7_decode_mvs(VP8Context *s, VP8Macroblock *mb,
                   int mb_x, int mb_y, int layout)
{
   enum { CNT_ZERO, CNT_NEAREST, CNT_NEAR };
   enum { VP8_EDGE_TOP, VP8_EDGE_LEFT, VP8_EDGE_TOPLEFT };
   int idx = CNT_ZERO;
   VP8mv near_mv[3];
   uint8_t cnt[3] = { 0 };
   VPXRangeCoder *c = &s->c;
   int i;

   AV_ZERO32(&near_mv[0]);
   AV_ZERO32(&near_mv[1]);
   AV_ZERO32(&near_mv[2]);

   for (i = 0; i < VP7_MV_PRED_COUNT; i++) {
       const VP7MVPred * pred = &vp7_mv_pred[i];
       int edge_x, edge_y;

       if (vp7_calculate_mb_offset(mb_x, mb_y, s->mb_width, pred->xoffset,
                                   pred->yoffset, !s->profile, &edge_x, &edge_y)) {
           const VP8Macroblock *edge = (s->mb_layout == 1)
                                     ? s->macroblocks_base + 1 + edge_x +
                                       (s->mb_width + 1) * (edge_y + 1)
                                     : s->macroblocks + edge_x +
                                       (s->mb_height - edge_y - 1) * 2;
           uint32_t mv = AV_RN32A(get_bmv_ptr(edge, vp7_mv_pred[i].subblock));
           if (mv) {
               if (AV_RN32A(&near_mv[CNT_NEAREST])) {
                   if (mv == AV_RN32A(&near_mv[CNT_NEAREST])) {
                       idx = CNT_NEAREST;
                   } else if (AV_RN32A(&near_mv[CNT_NEAR])) {
                       if (mv != AV_RN32A(&near_mv[CNT_NEAR]))
                           continue;
                       idx = CNT_NEAR;
                   } else {
                       AV_WN32A(&near_mv[CNT_NEAR], mv);
                       idx = CNT_NEAR;
                   }
               } else {
                   AV_WN32A(&near_mv[CNT_NEAREST], mv);
                   idx = CNT_NEAREST;
               }
           } else {
               idx = CNT_ZERO;
           }
       } else {
           idx = CNT_ZERO;
       }
       cnt[idx] += vp7_mv_pred[i].score;
   }

   mb->partitioning = VP8_SPLITMVMODE_NONE;

   if (vpx_rac_get_prob_branchy(c, vp7_mode_contexts[cnt[CNT_ZERO]][0])) {
       mb->mode = VP8_MVMODE_MV;

       if (vpx_rac_get_prob_branchy(c, vp7_mode_contexts[cnt[CNT_NEAREST]][1])) {

           if (vpx_rac_get_prob_branchy(c, vp7_mode_contexts[cnt[CNT_NEAR]][2])) {

               if (cnt[CNT_NEAREST] > cnt[CNT_NEAR])
                   AV_WN32A(&mb->mv, cnt[CNT_ZERO] > cnt[CNT_NEAREST] ? 0 : AV_RN32A(&near_mv[CNT_NEAREST]));
               else
                   AV_WN32A(&mb->mv, cnt[CNT_ZERO] > cnt[CNT_NEAR]    ? 0 : AV_RN32A(&near_mv[CNT_NEAR]));

               if (vpx_rac_get_prob_branchy(c, vp7_mode_contexts[cnt[CNT_NEAR]][3])) {
                   mb->mode = VP8_MVMODE_SPLIT;
                   mb->mv = mb->bmv[decode_splitmvs(s, c, mb, layout, IS_VP7) - 1];
               } else {
                   mb->mv.y += vp7_read_mv_component(c, s->prob->mvc[0]);
                   mb->mv.x += vp7_read_mv_component(c, s->prob->mvc[1]);
                   mb->bmv[0] = mb->mv;
               }
           } else {
               mb->mv = near_mv[CNT_NEAR];
               mb->bmv[0] = mb->mv;
           }
       } else {
           mb->mv = near_mv[CNT_NEAREST];
           mb->bmv[0] = mb->mv;
       }
   } else {
       mb->mode = VP8_MVMODE_ZERO;
       AV_ZERO32(&mb->mv);
       mb->bmv[0] = mb->mv;
   }
}

static av_always_inline
void vp8_decode_mvs(VP8Context *s, const VP8mvbounds *mv_bounds, VP8Macroblock *mb,
                   int mb_x, int mb_y, int layout)
{
   VP8Macroblock *mb_edge[3] = { 0      /* top */,
                                 mb - 1 /* left */,
                                 0      /* top-left */ };
   enum { CNT_ZERO, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV };
   enum { VP8_EDGE_TOP, VP8_EDGE_LEFT, VP8_EDGE_TOPLEFT };
   int idx = CNT_ZERO;
   int cur_sign_bias = s->sign_bias[mb->ref_frame];
   const int8_t *sign_bias = s->sign_bias;
   VP8mv near_mv[4];
   uint8_t cnt[4] = { 0 };
   VPXRangeCoder *c = &s->c;

   if (!layout) { // layout is inlined (s->mb_layout is not)
       mb_edge[0] = mb + 2;
       mb_edge[2] = mb + 1;
   } else {
       mb_edge[0] = mb - s->mb_width - 1;
       mb_edge[2] = mb - s->mb_width - 2;
   }

   AV_ZERO32(&near_mv[0]);
   AV_ZERO32(&near_mv[1]);
   AV_ZERO32(&near_mv[2]);

   /* Process MB on top, left and top-left */
#define MV_EDGE_CHECK(n)                                                      \
   {                                                                         \
       const VP8Macroblock *edge = mb_edge[n];                               \
       int edge_ref = edge->ref_frame;                                       \
       if (edge_ref != VP8_FRAME_CURRENT) {                                 \
           uint32_t mv = AV_RN32A(&edge->mv);                                \
           if (mv) {                                                         \
               if (cur_sign_bias != sign_bias[edge_ref]) {                   \
                   /* SWAR negate of the values in mv. */                    \
                   mv = ~mv;                                                 \
                   mv = ((mv & 0x7fff7fff) +                                 \
                         0x00010001) ^ (mv & 0x80008000);                    \
               }                                                             \
               if (!n || mv != AV_RN32A(&near_mv[idx]))                      \
                   AV_WN32A(&near_mv[++idx], mv);                            \
               cnt[idx] += 1 + (n != 2);                                     \
           } else                                                            \
               cnt[CNT_ZERO] += 1 + (n != 2);                                \
       }                                                                     \
   }

   MV_EDGE_CHECK(0)
   MV_EDGE_CHECK(1)
   MV_EDGE_CHECK(2)

   mb->partitioning = VP8_SPLITMVMODE_NONE;
   if (vpx_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_ZERO]][0])) {
       mb->mode = VP8_MVMODE_MV;

       /* If we have three distinct MVs, merge first and last if they're the same */
       if (cnt[CNT_SPLITMV] &&
           AV_RN32A(&near_mv[1 + VP8_EDGE_TOP]) == AV_RN32A(&near_mv[1 + VP8_EDGE_TOPLEFT]))
           cnt[CNT_NEAREST] += 1;

       /* Swap near and nearest if necessary */
       if (cnt[CNT_NEAR] > cnt[CNT_NEAREST]) {
           FFSWAP(uint8_t,     cnt[CNT_NEAREST],     cnt[CNT_NEAR]);
           FFSWAP(VP8mv,   near_mv[CNT_NEAREST], near_mv[CNT_NEAR]);
       }

       if (vpx_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_NEAREST]][1])) {
           if (vpx_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_NEAR]][2])) {
               /* Choose the best mv out of 0,0 and the nearest mv */
               clamp_mv(mv_bounds, &mb->mv, &near_mv[CNT_ZERO + (cnt[CNT_NEAREST] >= cnt[CNT_ZERO])]);
               cnt[CNT_SPLITMV] = ((mb_edge[VP8_EDGE_LEFT]->mode    == VP8_MVMODE_SPLIT) +
                                   (mb_edge[VP8_EDGE_TOP]->mode     == VP8_MVMODE_SPLIT)) * 2 +
                                   (mb_edge[VP8_EDGE_TOPLEFT]->mode == VP8_MVMODE_SPLIT);

               if (vpx_rac_get_prob_branchy(c, vp8_mode_contexts[cnt[CNT_SPLITMV]][3])) {
                   mb->mode = VP8_MVMODE_SPLIT;
                   mb->mv = mb->bmv[decode_splitmvs(s, c, mb, layout, IS_VP8) - 1];
               } else {
                   mb->mv.y  += vp8_read_mv_component(c, s->prob->mvc[0]);
                   mb->mv.x  += vp8_read_mv_component(c, s->prob->mvc[1]);
                   mb->bmv[0] = mb->mv;
               }
           } else {
               clamp_mv(mv_bounds, &mb->mv, &near_mv[CNT_NEAR]);
               mb->bmv[0] = mb->mv;
           }
       } else {
           clamp_mv(mv_bounds, &mb->mv, &near_mv[CNT_NEAREST]);
           mb->bmv[0] = mb->mv;
       }
   } else {
       mb->mode = VP8_MVMODE_ZERO;
       AV_ZERO32(&mb->mv);
       mb->bmv[0] = mb->mv;
   }
}

static av_always_inline
void decode_intra4x4_modes(VP8Context *s, VPXRangeCoder *c, VP8Macroblock *mb,
                          int mb_x, int keyframe, int layout)
{
   uint8_t *intra4x4 = mb->intra4x4_pred_mode_mb;

   if (layout) {
       VP8Macroblock *mb_top = mb - s->mb_width - 1;
       memcpy(mb->intra4x4_pred_mode_top, mb_top->intra4x4_pred_mode_top, 4);
   }
   if (keyframe) {
       int x, y;
       uint8_t *top;
       uint8_t *const left = s->intra4x4_pred_mode_left;
       if (layout)
           top = mb->intra4x4_pred_mode_top;
       else
           top = s->intra4x4_pred_mode_top + 4 * mb_x;
       for (y = 0; y < 4; y++) {
           for (x = 0; x < 4; x++) {
               const uint8_t *ctx;
               ctx       = vp8_pred4x4_prob_intra[top[x]][left[y]];
               *intra4x4 = vp89_rac_get_tree(c, vp8_pred4x4_tree, ctx);
               left[y]   = top[x] = *intra4x4;
               intra4x4++;
           }
       }
   } else {
       int i;
       for (i = 0; i < 16; i++)
           intra4x4[i] = vp89_rac_get_tree(c, vp8_pred4x4_tree,
                                           vp8_pred4x4_prob_inter);
   }
}

static av_always_inline
void decode_mb_mode(VP8Context *s, const VP8mvbounds *mv_bounds,
                   VP8Macroblock *mb, int mb_x, int mb_y,
                   uint8_t *segment, const uint8_t *ref, int layout, int is_vp7)
{
   VPXRangeCoder *c = &s->c;
   static const char * const vp7_feature_name[] = { "q-index",
                                                    "lf-delta",
                                                    "partial-golden-update",
                                                    "blit-pitch" };
   if (is_vp7) {
       int i;
       *segment = 0;
       for (i = 0; i < 4; i++) {
           if (s->feature_enabled[i]) {
               if (vpx_rac_get_prob_branchy(c, s->feature_present_prob[i])) {
                     int index = vp89_rac_get_tree(c, vp7_feature_index_tree,
                                                   s->feature_index_prob[i]);
                     av_log(s->avctx, AV_LOG_WARNING,
                            "Feature %s present in macroblock (value 0x%x)\n",
                            vp7_feature_name[i], s->feature_value[i][index]);
               }
          }
       }
   } else if (s->segmentation.update_map) {
       int bit  = vpx_rac_get_prob(c, s->prob->segmentid[0]);
       *segment = vpx_rac_get_prob(c, s->prob->segmentid[1+bit]) + 2*bit;
   } else if (s->segmentation.enabled)
       *segment = ref ? *ref : *segment;
   mb->segment = *segment;

   mb->skip = s->mbskip_enabled ? vpx_rac_get_prob(c, s->prob->mbskip) : 0;

   if (s->keyframe) {
       mb->mode = vp89_rac_get_tree(c, vp8_pred16x16_tree_intra,
                                    vp8_pred16x16_prob_intra);

       if (mb->mode == MODE_I4x4) {
           decode_intra4x4_modes(s, c, mb, mb_x, 1, layout);
       } else {
           const uint32_t modes = (is_vp7 ? vp7_pred4x4_mode
                                          : vp8_pred4x4_mode)[mb->mode] * 0x01010101u;
           if (s->mb_layout)
               AV_WN32A(mb->intra4x4_pred_mode_top, modes);
           else
               AV_WN32A(s->intra4x4_pred_mode_top + 4 * mb_x, modes);
           AV_WN32A(s->intra4x4_pred_mode_left, modes);
       }

       mb->chroma_pred_mode = vp89_rac_get_tree(c, vp8_pred8x8c_tree,
                                                vp8_pred8x8c_prob_intra);
       mb->ref_frame        = VP8_FRAME_CURRENT;
   } else if (vpx_rac_get_prob_branchy(c, s->prob->intra)) {
       // inter MB, 16.2
       if (vpx_rac_get_prob_branchy(c, s->prob->last))
           mb->ref_frame =
               (!is_vp7 && vpx_rac_get_prob(c, s->prob->golden)) ? VP8_FRAME_ALTREF
                                                                 : VP8_FRAME_GOLDEN;
       else
           mb->ref_frame = VP8_FRAME_PREVIOUS;
       s->ref_count[mb->ref_frame - 1]++;

       // motion vectors, 16.3
       if (is_vp7)
           vp7_decode_mvs(s, mb, mb_x, mb_y, layout);
       else
           vp8_decode_mvs(s, mv_bounds, mb, mb_x, mb_y, layout);
   } else {
       // intra MB, 16.1
       mb->mode = vp89_rac_get_tree(c, vp8_pred16x16_tree_inter,
                                    s->prob->pred16x16);

       if (mb->mode == MODE_I4x4)
           decode_intra4x4_modes(s, c, mb, mb_x, 0, layout);

       mb->chroma_pred_mode = vp89_rac_get_tree(c, vp8_pred8x8c_tree,
                                                s->prob->pred8x8c);
       mb->ref_frame        = VP8_FRAME_CURRENT;
       mb->partitioning     = VP8_SPLITMVMODE_NONE;
       AV_ZERO32(&mb->bmv[0]);
   }
}

/**
* @param r     arithmetic bitstream reader context
* @param block destination for block coefficients
* @param probs probabilities to use when reading trees from the bitstream
* @param i     initial coeff index, 0 unless a separate DC block is coded
* @param qmul  array holding the dc/ac dequant factor at position 0/1
*
* @return 0 if no coeffs were decoded
*         otherwise, the index of the last coeff decoded plus one
*/
static av_always_inline
int decode_block_coeffs_internal(VPXRangeCoder *r, int16_t block[16],
                                uint8_t probs[16][3][NUM_DCT_TOKENS - 1],
                                int i, const uint8_t *token_prob, const int16_t qmul[2],
                                const uint8_t scan[16], int vp7)
{
   VPXRangeCoder c = *r;
   goto skip_eob;
   do {
       int coeff;
restart:
       if (!vpx_rac_get_prob_branchy(&c, token_prob[0]))   // DCT_EOB
           break;

skip_eob:
       if (!vpx_rac_get_prob_branchy(&c, token_prob[1])) { // DCT_0
           if (++i == 16)
               break; // invalid input; blocks should end with EOB
           token_prob = probs[i][0];
           if (vp7)
               goto restart;
           goto skip_eob;
       }

       if (!vpx_rac_get_prob_branchy(&c, token_prob[2])) { // DCT_1
           coeff = 1;
           token_prob = probs[i + 1][1];
       } else {
           if (!vpx_rac_get_prob_branchy(&c, token_prob[3])) { // DCT 2,3,4
               coeff = vpx_rac_get_prob_branchy(&c, token_prob[4]);
               if (coeff)
                   coeff += vpx_rac_get_prob(&c, token_prob[5]);
               coeff += 2;
           } else {
               // DCT_CAT*
               if (!vpx_rac_get_prob_branchy(&c, token_prob[6])) {
                   if (!vpx_rac_get_prob_branchy(&c, token_prob[7])) { // DCT_CAT1
                       coeff = 5 + vpx_rac_get_prob(&c, vp8_dct_cat1_prob[0]);
                   } else {                                    // DCT_CAT2
                       coeff  = 7;
                       coeff += vpx_rac_get_prob(&c, vp8_dct_cat2_prob[0]) << 1;
                       coeff += vpx_rac_get_prob(&c, vp8_dct_cat2_prob[1]);
                   }
               } else {    // DCT_CAT3 and up
                   int a   = vpx_rac_get_prob(&c, token_prob[8]);
                   int b   = vpx_rac_get_prob(&c, token_prob[9 + a]);
                   int cat = (a << 1) + b;
                   coeff  = 3 + (8 << cat);
                   coeff += vp8_rac_get_coeff(&c, ff_vp8_dct_cat_prob[cat]);
               }
           }
           token_prob = probs[i + 1][2];
       }
       block[scan[i]] = (vp89_rac_get(&c) ? -coeff : coeff) * qmul[!!i];
   } while (++i < 16);

   *r = c;
   return i;
}

static av_always_inline
int inter_predict_dc(int16_t block[16], int16_t pred[2])
{
   int16_t dc = block[0];
   int ret = 0;

   if (pred[1] > 3) {
       dc += pred[0];
       ret = 1;
   }

   if (!pred[0] | !dc | ((int32_t)pred[0] ^ (int32_t)dc) >> 31) {
       block[0] = pred[0] = dc;
       pred[1] = 0;
   } else {
       if (pred[0] == dc)
           pred[1]++;
       block[0] = pred[0] = dc;
   }

   return ret;
}

static int vp7_decode_block_coeffs_internal(VPXRangeCoder *r,
                                           int16_t block[16],
                                           uint8_t probs[16][3][NUM_DCT_TOKENS - 1],
                                           int i, const uint8_t *token_prob,
                                           const int16_t qmul[2],
                                           const uint8_t scan[16])
{
   return decode_block_coeffs_internal(r, block, probs, i,
                                       token_prob, qmul, scan, IS_VP7);
}

#ifndef vp8_decode_block_coeffs_internal
static int vp8_decode_block_coeffs_internal(VPXRangeCoder *r,
                                           int16_t block[16],
                                           uint8_t probs[16][3][NUM_DCT_TOKENS - 1],
                                           int i, const uint8_t *token_prob,
                                           const int16_t qmul[2])
{
   return decode_block_coeffs_internal(r, block, probs, i,
                                       token_prob, qmul, ff_zigzag_scan, IS_VP8);
}
#endif

/**
* @param c          arithmetic bitstream reader context
* @param block      destination for block coefficients
* @param probs      probabilities to use when reading trees from the bitstream
* @param i          initial coeff index, 0 unless a separate DC block is coded
* @param zero_nhood the initial prediction context for number of surrounding
*                   all-zero blocks (only left/top, so 0-2)
* @param qmul       array holding the dc/ac dequant factor at position 0/1
* @param scan       scan pattern (VP7 only)
*
* @return 0 if no coeffs were decoded
*         otherwise, the index of the last coeff decoded plus one
*/
static av_always_inline
int decode_block_coeffs(VPXRangeCoder *c, int16_t block[16],
                       uint8_t probs[16][3][NUM_DCT_TOKENS - 1],
                       int i, int zero_nhood, const int16_t qmul[2],
                       const uint8_t scan[16], int vp7)
{
   const uint8_t *token_prob = probs[i][zero_nhood];
   if (!vpx_rac_get_prob_branchy(c, token_prob[0]))   // DCT_EOB
       return 0;
   return vp7 ? vp7_decode_block_coeffs_internal(c, block, probs, i,
                                                 token_prob, qmul, scan)
              : vp8_decode_block_coeffs_internal(c, block, probs, i,
                                                 token_prob, qmul);
}

static av_always_inline
void decode_mb_coeffs(VP8Context *s, VP8ThreadData *td, VPXRangeCoder *c,
                     VP8Macroblock *mb, uint8_t t_nnz[9], uint8_t l_nnz[9],
                     int is_vp7)
{
   int i, x, y, luma_start = 0, luma_ctx = 3;
   int nnz_pred, nnz, nnz_total = 0;
   int segment = mb->segment;
   int block_dc = 0;

   if (mb->mode != MODE_I4x4 && (is_vp7 || mb->mode != VP8_MVMODE_SPLIT)) {
       nnz_pred = t_nnz[8] + l_nnz[8];

       // decode DC values and do hadamard
       nnz = decode_block_coeffs(c, td->block_dc, s->prob->token[1], 0,
                                 nnz_pred, s->qmat[segment].luma_dc_qmul,
                                 ff_zigzag_scan, is_vp7);
       l_nnz[8] = t_nnz[8] = !!nnz;

       if (is_vp7 && mb->mode > MODE_I4x4) {
           nnz |=  inter_predict_dc(td->block_dc,
                                    s->inter_dc_pred[mb->ref_frame - 1]);
       }

       if (nnz) {
           nnz_total += nnz;
           block_dc   = 1;
           if (nnz == 1)
               s->vp8dsp.vp8_luma_dc_wht_dc(td->block, td->block_dc);
           else
               s->vp8dsp.vp8_luma_dc_wht(td->block, td->block_dc);
       }
       luma_start = 1;
       luma_ctx   = 0;
   }

   // luma blocks
   for (y = 0; y < 4; y++)
       for (x = 0; x < 4; x++) {
           nnz_pred = l_nnz[y] + t_nnz[x];
           nnz = decode_block_coeffs(c, td->block[y][x],
                                     s->prob->token[luma_ctx],
                                     luma_start, nnz_pred,
                                     s->qmat[segment].luma_qmul,
                                     s->prob[0].scan, is_vp7);
           /* nnz+block_dc may be one more than the actual last index,
            * but we don't care */
           td->non_zero_count_cache[y][x] = nnz + block_dc;
           t_nnz[x] = l_nnz[y] = !!nnz;
           nnz_total += nnz;
       }

   // chroma blocks
   // TODO: what to do about dimensions? 2nd dim for luma is x,
   // but for chroma it's (y<<1)|x
   for (i = 4; i < 6; i++)
       for (y = 0; y < 2; y++)
           for (x = 0; x < 2; x++) {
               nnz_pred = l_nnz[i + 2 * y] + t_nnz[i + 2 * x];
               nnz = decode_block_coeffs(c, td->block[i][(y << 1) + x],
                                         s->prob->token[2], 0, nnz_pred,
                                         s->qmat[segment].chroma_qmul,
                                         s->prob[0].scan, is_vp7);
               td->non_zero_count_cache[i][(y << 1) + x] = nnz;
               t_nnz[i + 2 * x] = l_nnz[i + 2 * y] = !!nnz;
               nnz_total += nnz;
           }

   // if there were no coded coeffs despite the macroblock not being marked skip,
   // we MUST not do the inner loop filter and should not do IDCT
   // Since skip isn't used for bitstream prediction, just manually set it.
   if (!nnz_total)
       mb->skip = 1;
}

static av_always_inline
void backup_mb_border(uint8_t *top_border, const uint8_t *src_y,
                     const uint8_t *src_cb, const uint8_t *src_cr,
                     ptrdiff_t linesize, ptrdiff_t uvlinesize, int simple)
{
   AV_COPY128(top_border, src_y + 15 * linesize);
   if (!simple) {
       AV_COPY64(top_border + 16, src_cb + 7 * uvlinesize);
       AV_COPY64(top_border + 24, src_cr + 7 * uvlinesize);
   }
}

static av_always_inline
void xchg_mb_border(uint8_t *top_border, uint8_t *src_y, uint8_t *src_cb,
                   uint8_t *src_cr, ptrdiff_t linesize, ptrdiff_t uvlinesize, int mb_x,
                   int mb_y, int mb_width, int simple, int xchg)
{
   uint8_t *top_border_m1 = top_border - 32;     // for TL prediction
   src_y  -= linesize;
   src_cb -= uvlinesize;
   src_cr -= uvlinesize;

#define XCHG(a, b, xchg)                                                      \
   do {                                                                      \
       if (xchg)                                                             \
           AV_SWAP64(b, a);                                                  \
       else                                                                  \
           AV_COPY64(b, a);                                                  \
   } while (0)

   XCHG(top_border_m1 + 8, src_y - 8, xchg);
   XCHG(top_border, src_y, xchg);
   XCHG(top_border + 8, src_y + 8, 1);
   if (mb_x < mb_width - 1)
       XCHG(top_border + 32, src_y + 16, 1);

   // only copy chroma for normal loop filter
   // or to initialize the top row to 127
   if (!simple || !mb_y) {
       XCHG(top_border_m1 + 16, src_cb - 8, xchg);
       XCHG(top_border_m1 + 24, src_cr - 8, xchg);
       XCHG(top_border + 16, src_cb, 1);
       XCHG(top_border + 24, src_cr, 1);
   }
}

static av_always_inline
int check_dc_pred8x8_mode(int mode, int mb_x, int mb_y)
{
   if (!mb_x)
       return mb_y ? TOP_DC_PRED8x8 : DC_128_PRED8x8;
   else
       return mb_y ? mode : LEFT_DC_PRED8x8;
}

static av_always_inline
int check_tm_pred8x8_mode(int mode, int mb_x, int mb_y, int vp7)
{
   if (!mb_x)
       return mb_y ? VERT_PRED8x8 : (vp7 ? DC_128_PRED8x8 : DC_129_PRED8x8);
   else
       return mb_y ? mode : HOR_PRED8x8;
}

static av_always_inline
int check_intra_pred8x8_mode_emuedge(int mode, int mb_x, int mb_y, int vp7)
{
   switch (mode) {
   case DC_PRED8x8:
       return check_dc_pred8x8_mode(mode, mb_x, mb_y);
   case VERT_PRED8x8:
       return !mb_y ? (vp7 ? DC_128_PRED8x8 : DC_127_PRED8x8) : mode;
   case HOR_PRED8x8:
       return !mb_x ? (vp7 ? DC_128_PRED8x8 : DC_129_PRED8x8) : mode;
   case PLANE_PRED8x8: /* TM */
       return check_tm_pred8x8_mode(mode, mb_x, mb_y, vp7);
   }
   return mode;
}

static av_always_inline
int check_tm_pred4x4_mode(int mode, int mb_x, int mb_y, int vp7)
{
   if (!mb_x) {
       return mb_y ? VERT_VP8_PRED : (vp7 ? DC_128_PRED : DC_129_PRED);
   } else {
       return mb_y ? mode : HOR_VP8_PRED;
   }
}

static av_always_inline
int check_intra_pred4x4_mode_emuedge(int mode, int mb_x, int mb_y,
                                    int *copy_buf, int vp7)
{
   switch (mode) {
   case VERT_PRED:
       if (!mb_x && mb_y) {
           *copy_buf = 1;
           return mode;
       }
       /* fall-through */
   case DIAG_DOWN_LEFT_PRED:
   case VERT_LEFT_PRED:
       return !mb_y ? (vp7 ? DC_128_PRED : DC_127_PRED) : mode;
   case HOR_PRED:
       if (!mb_y) {
           *copy_buf = 1;
           return mode;
       }
       /* fall-through */
   case HOR_UP_PRED:
       return !mb_x ? (vp7 ? DC_128_PRED : DC_129_PRED) : mode;
   case TM_VP8_PRED:
       return check_tm_pred4x4_mode(mode, mb_x, mb_y, vp7);
   case DC_PRED: /* 4x4 DC doesn't use the same "H.264-style" exceptions
                  * as 16x16/8x8 DC */
   case DIAG_DOWN_RIGHT_PRED:
   case VERT_RIGHT_PRED:
   case HOR_DOWN_PRED:
       if (!mb_y || !mb_x)
           *copy_buf = 1;
       return mode;
   }
   return mode;
}

static av_always_inline
void intra_predict(VP8Context *s, VP8ThreadData *td, uint8_t *const dst[3],
                  VP8Macroblock *mb, int mb_x, int mb_y, int is_vp7)
{
   int x, y, mode, nnz;
   uint32_t tr;

   /* for the first row, we need to run xchg_mb_border to init the top edge
    * to 127 otherwise, skip it if we aren't going to deblock */
   if (mb_y && (s->deblock_filter || !mb_y) && td->thread_nr == 0)
       xchg_mb_border(s->top_border[mb_x + 1], dst[0], dst[1], dst[2],
                      s->linesize, s->uvlinesize, mb_x, mb_y, s->mb_width,
                      s->filter.simple, 1);

   if (mb->mode < MODE_I4x4) {
       mode = check_intra_pred8x8_mode_emuedge(mb->mode, mb_x, mb_y, is_vp7);
       s->hpc.pred16x16[mode](dst[0], s->linesize);
   } else {
       uint8_t *ptr = dst[0];
       const uint8_t *intra4x4 = mb->intra4x4_pred_mode_mb;
       const uint8_t lo = is_vp7 ? 128 : 127;
       const uint8_t hi = is_vp7 ? 128 : 129;
       const uint8_t tr_top[4] = { lo, lo, lo, lo };

       // all blocks on the right edge of the macroblock use bottom edge
       // the top macroblock for their topright edge
       const uint8_t *tr_right = ptr - s->linesize + 16;

       // if we're on the right edge of the frame, said edge is extended
       // from the top macroblock
       if (mb_y && mb_x == s->mb_width - 1) {
           tr       = tr_right[-1] * 0x01010101u;
           tr_right = (uint8_t *) &tr;
       }

       if (mb->skip)
           AV_ZERO128(td->non_zero_count_cache);

       for (y = 0; y < 4; y++) {
           const uint8_t *topright = ptr + 4 - s->linesize;
           for (x = 0; x < 4; x++) {
               int copy = 0;
               ptrdiff_t linesize = s->linesize;
               uint8_t *dst = ptr + 4 * x;
               LOCAL_ALIGNED(4, uint8_t, copy_dst, [5 * 8]);

               if ((y == 0 || x == 3) && mb_y == 0) {
                   topright = tr_top;
               } else if (x == 3)
                   topright = tr_right;

               mode = check_intra_pred4x4_mode_emuedge(intra4x4[x], mb_x + x,
                                                       mb_y + y, &copy, is_vp7);
               if (copy) {
                   dst      = copy_dst + 12;
                   linesize = 8;
                   if (!(mb_y + y)) {
                       copy_dst[3] = lo;
                       AV_WN32A(copy_dst + 4, lo * 0x01010101U);
                   } else {
                       AV_COPY32(copy_dst + 4, ptr + 4 * x - s->linesize);
                       if (!(mb_x + x)) {
                           copy_dst[3] = hi;
                       } else {
                           copy_dst[3] = ptr[4 * x - s->linesize - 1];
                       }
                   }
                   if (!(mb_x + x)) {
                       copy_dst[11] =
                       copy_dst[19] =
                       copy_dst[27] =
                       copy_dst[35] = hi;
                   } else {
                       copy_dst[11] = ptr[4 * x                   - 1];
                       copy_dst[19] = ptr[4 * x + s->linesize     - 1];
                       copy_dst[27] = ptr[4 * x + s->linesize * 2 - 1];
                       copy_dst[35] = ptr[4 * x + s->linesize * 3 - 1];
                   }
               }
               s->hpc.pred4x4[mode](dst, topright, linesize);
               if (copy) {
                   AV_COPY32(ptr + 4 * x,                   copy_dst + 12);
                   AV_COPY32(ptr + 4 * x + s->linesize,     copy_dst + 20);
                   AV_COPY32(ptr + 4 * x + s->linesize * 2, copy_dst + 28);
                   AV_COPY32(ptr + 4 * x + s->linesize * 3, copy_dst + 36);
               }

               nnz = td->non_zero_count_cache[y][x];
               if (nnz) {
                   if (nnz == 1)
                       s->vp8dsp.vp8_idct_dc_add(ptr + 4 * x,
                                                 td->block[y][x], s->linesize);
                   else
                       s->vp8dsp.vp8_idct_add(ptr + 4 * x,
                                              td->block[y][x], s->linesize);
               }
               topright += 4;
           }

           ptr      += 4 * s->linesize;
           intra4x4 += 4;
       }
   }

   mode = check_intra_pred8x8_mode_emuedge(mb->chroma_pred_mode,
                                           mb_x, mb_y, is_vp7);
   s->hpc.pred8x8[mode](dst[1], s->uvlinesize);
   s->hpc.pred8x8[mode](dst[2], s->uvlinesize);

   if (mb_y && (s->deblock_filter || !mb_y) && td->thread_nr == 0)
       xchg_mb_border(s->top_border[mb_x + 1], dst[0], dst[1], dst[2],
                      s->linesize, s->uvlinesize, mb_x, mb_y, s->mb_width,
                      s->filter.simple, 0);
}

static const uint8_t subpel_idx[3][8] = {
   { 0, 1, 2, 1, 2, 1, 2, 1 }, // nr. of left extra pixels,
                               // also function pointer index
   { 0, 3, 5, 3, 5, 3, 5, 3 }, // nr. of extra pixels required
   { 0, 2, 3, 2, 3, 2, 3, 2 }, // nr. of right extra pixels
};

/**
* luma MC function
*
* @param s        VP8 decoding context
* @param dst      target buffer for block data at block position
* @param ref      reference picture buffer at origin (0, 0)
* @param mv       motion vector (relative to block position) to get pixel data from
* @param x_off    horizontal position of block from origin (0, 0)
* @param y_off    vertical position of block from origin (0, 0)
* @param block_w  width of block (16, 8 or 4)
* @param block_h  height of block (always same as block_w)
* @param width    width of src/dst plane data
* @param height   height of src/dst plane data
* @param linesize size of a single line of plane data, including padding
* @param mc_func  motion compensation function pointers (bilinear or sixtap MC)
*/
static av_always_inline
void vp8_mc_luma(VP8Context *s, VP8ThreadData *td, uint8_t *dst,
                const ProgressFrame *ref, const VP8mv *mv,
                int x_off, int y_off, int block_w, int block_h,
                int width, int height, ptrdiff_t linesize,
                vp8_mc_func mc_func[3][3])
{
   const uint8_t *src = ref->f->data[0];

   if (AV_RN32A(mv)) {
       ptrdiff_t src_linesize = linesize;

       int mx = (mv->x * 2) & 7, mx_idx = subpel_idx[0][mx];
       int my = (mv->y * 2) & 7, my_idx = subpel_idx[0][my];

       x_off += mv->x >> 2;
       y_off += mv->y >> 2;

       // edge emulation
       ff_progress_frame_await(ref, (3 + y_off + block_h + subpel_idx[2][my]) >> 4);
       src += y_off * linesize + x_off;
       if (x_off < mx_idx || x_off >= width  - block_w - subpel_idx[2][mx] ||
           y_off < my_idx || y_off >= height - block_h - subpel_idx[2][my]) {
           s->vdsp.emulated_edge_mc(td->edge_emu_buffer,
                                    src - my_idx * linesize - mx_idx,
                                    EDGE_EMU_LINESIZE, linesize,
                                    block_w + subpel_idx[1][mx],
                                    block_h + subpel_idx[1][my],
                                    x_off - mx_idx, y_off - my_idx,
                                    width, height);
           src = td->edge_emu_buffer + mx_idx + EDGE_EMU_LINESIZE * my_idx;
           src_linesize = EDGE_EMU_LINESIZE;
       }
       mc_func[my_idx][mx_idx](dst, linesize, src, src_linesize, block_h, mx, my);
   } else {
       ff_progress_frame_await(ref, (3 + y_off + block_h) >> 4);
       mc_func[0][0](dst, linesize, src + y_off * linesize + x_off,
                     linesize, block_h, 0, 0);
   }
}

/**
* chroma MC function
*
* @param s        VP8 decoding context
* @param dst1     target buffer for block data at block position (U plane)
* @param dst2     target buffer for block data at block position (V plane)
* @param ref      reference picture buffer at origin (0, 0)
* @param mv       motion vector (relative to block position) to get pixel data from
* @param x_off    horizontal position of block from origin (0, 0)
* @param y_off    vertical position of block from origin (0, 0)
* @param block_w  width of block (16, 8 or 4)
* @param block_h  height of block (always same as block_w)
* @param width    width of src/dst plane data
* @param height   height of src/dst plane data
* @param linesize size of a single line of plane data, including padding
* @param mc_func  motion compensation function pointers (bilinear or sixtap MC)
*/
static av_always_inline
void vp8_mc_chroma(VP8Context *s, VP8ThreadData *td, uint8_t *dst1,
                  uint8_t *dst2, const ProgressFrame *ref, const VP8mv *mv,
                  int x_off, int y_off, int block_w, int block_h,
                  int width, int height, ptrdiff_t linesize,
                  vp8_mc_func mc_func[3][3])
{
   const uint8_t *src1 = ref->f->data[1], *src2 = ref->f->data[2];

   if (AV_RN32A(mv)) {
       int mx = mv->x & 7, mx_idx = subpel_idx[0][mx];
       int my = mv->y & 7, my_idx = subpel_idx[0][my];

       x_off += mv->x >> 3;
       y_off += mv->y >> 3;

       // edge emulation
       src1 += y_off * linesize + x_off;
       src2 += y_off * linesize + x_off;
       ff_progress_frame_await(ref, (3 + y_off + block_h + subpel_idx[2][my]) >> 3);
       if (x_off < mx_idx || x_off >= width  - block_w - subpel_idx[2][mx] ||
           y_off < my_idx || y_off >= height - block_h - subpel_idx[2][my]) {
           s->vdsp.emulated_edge_mc(td->edge_emu_buffer,
                                    src1 - my_idx * linesize - mx_idx,
                                    EDGE_EMU_LINESIZE, linesize,
                                    block_w + subpel_idx[1][mx],
                                    block_h + subpel_idx[1][my],
                                    x_off - mx_idx, y_off - my_idx, width, height);
           src1 = td->edge_emu_buffer + mx_idx + EDGE_EMU_LINESIZE * my_idx;
           mc_func[my_idx][mx_idx](dst1, linesize, src1, EDGE_EMU_LINESIZE, block_h, mx, my);

           s->vdsp.emulated_edge_mc(td->edge_emu_buffer,
                                    src2 - my_idx * linesize - mx_idx,
                                    EDGE_EMU_LINESIZE, linesize,
                                    block_w + subpel_idx[1][mx],
                                    block_h + subpel_idx[1][my],
                                    x_off - mx_idx, y_off - my_idx, width, height);
           src2 = td->edge_emu_buffer + mx_idx + EDGE_EMU_LINESIZE * my_idx;
           mc_func[my_idx][mx_idx](dst2, linesize, src2, EDGE_EMU_LINESIZE, block_h, mx, my);
       } else {
           mc_func[my_idx][mx_idx](dst1, linesize, src1, linesize, block_h, mx, my);
           mc_func[my_idx][mx_idx](dst2, linesize, src2, linesize, block_h, mx, my);
       }
   } else {
       ff_progress_frame_await(ref, (3 + y_off + block_h) >> 3);
       mc_func[0][0](dst1, linesize, src1 + y_off * linesize + x_off, linesize, block_h, 0, 0);
       mc_func[0][0](dst2, linesize, src2 + y_off * linesize + x_off, linesize, block_h, 0, 0);
   }
}

static av_always_inline
void vp8_mc_part(VP8Context *s, VP8ThreadData *td, uint8_t *const dst[3],
                const ProgressFrame *ref_frame, int x_off, int y_off,
                int bx_off, int by_off, int block_w, int block_h,
                int width, int height, const VP8mv *mv)
{
   VP8mv uvmv = *mv;

   /* Y */
   vp8_mc_luma(s, td, dst[0] + by_off * s->linesize + bx_off,
               ref_frame, mv, x_off + bx_off, y_off + by_off,
               block_w, block_h, width, height, s->linesize,
               s->put_pixels_tab[block_w == 8]);

   /* U/V */
   if (s->profile == 3) {
       /* this block only applies VP8; it is safe to check
        * only the profile, as VP7 profile <= 1 */
       uvmv.x &= ~7;
       uvmv.y &= ~7;
   }
   x_off   >>= 1;
   y_off   >>= 1;
   bx_off  >>= 1;
   by_off  >>= 1;
   width   >>= 1;
   height  >>= 1;
   block_w >>= 1;
   block_h >>= 1;
   vp8_mc_chroma(s, td, dst[1] + by_off * s->uvlinesize + bx_off,
                 dst[2] + by_off * s->uvlinesize + bx_off, ref_frame,
                 &uvmv, x_off + bx_off, y_off + by_off,
                 block_w, block_h, width, height, s->uvlinesize,
                 s->put_pixels_tab[1 + (block_w == 4)]);
}

/* Fetch pixels for estimated mv 4 macroblocks ahead.
* Optimized for 64-byte cache lines. Inspired by ffh264 prefetch_motion. */
static av_always_inline
void prefetch_motion(const VP8Context *s, const VP8Macroblock *mb,
                    int mb_x, int mb_y, int mb_xy, int ref)
{
   /* Don't prefetch refs that haven't been used very often this frame. */
   if (s->ref_count[ref - 1] > (mb_xy >> 5)) {
       int x_off = mb_x << 4, y_off = mb_y << 4;
       int mx = (mb->mv.x >> 2) + x_off + 8;
       int my = (mb->mv.y >> 2) + y_off;
       uint8_t **src = s->framep[ref]->tf.f->data;
       int off = mx + (my + (mb_x & 3) * 4) * s->linesize + 64;
       /* For threading, a ff_thread_await_progress here might be useful, but
        * it actually slows down the decoder. Since a bad prefetch doesn't
        * generate bad decoder output, we don't run it here. */
       s->vdsp.prefetch(src[0] + off, s->linesize, 4);
       off = (mx >> 1) + ((my >> 1) + (mb_x & 7)) * s->uvlinesize + 64;
       s->vdsp.prefetch(src[1] + off, src[2] - src[1], 2);
   }
}

/**
* Apply motion vectors to prediction buffer, chapter 18.
*/
static av_always_inline
void inter_predict(VP8Context *s, VP8ThreadData *td, uint8_t *const dst[3],
                  VP8Macroblock *mb, int mb_x, int mb_y)
{
   int x_off = mb_x << 4, y_off = mb_y << 4;
   int width = 16 * s->mb_width, height = 16 * s->mb_height;
   const ProgressFrame *ref = &s->framep[mb->ref_frame]->tf;
   const VP8mv *bmv = mb->bmv;

   switch (mb->partitioning) {
   case VP8_SPLITMVMODE_NONE:
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   0, 0, 16, 16, width, height, &mb->mv);
       break;
   case VP8_SPLITMVMODE_4x4: {
       int x, y;
       VP8mv uvmv;

       /* Y */
       for (y = 0; y < 4; y++) {
           for (x = 0; x < 4; x++) {
               vp8_mc_luma(s, td, dst[0] + 4 * y * s->linesize + x * 4,
                           ref, &bmv[4 * y + x],
                           4 * x + x_off, 4 * y + y_off, 4, 4,
                           width, height, s->linesize,
                           s->put_pixels_tab[2]);
           }
       }

       /* U/V */
       x_off  >>= 1;
       y_off  >>= 1;
       width  >>= 1;
       height >>= 1;
       for (y = 0; y < 2; y++) {
           for (x = 0; x < 2; x++) {
               uvmv.x = mb->bmv[2 * y       * 4 + 2 * x    ].x +
                        mb->bmv[2 * y       * 4 + 2 * x + 1].x +
                        mb->bmv[(2 * y + 1) * 4 + 2 * x    ].x +
                        mb->bmv[(2 * y + 1) * 4 + 2 * x + 1].x;
               uvmv.y = mb->bmv[2 * y       * 4 + 2 * x    ].y +
                        mb->bmv[2 * y       * 4 + 2 * x + 1].y +
                        mb->bmv[(2 * y + 1) * 4 + 2 * x    ].y +
                        mb->bmv[(2 * y + 1) * 4 + 2 * x + 1].y;
               uvmv.x = (uvmv.x + 2 + FF_SIGNBIT(uvmv.x)) >> 2;
               uvmv.y = (uvmv.y + 2 + FF_SIGNBIT(uvmv.y)) >> 2;
               if (s->profile == 3) {
                   uvmv.x &= ~7;
                   uvmv.y &= ~7;
               }
               vp8_mc_chroma(s, td, dst[1] + 4 * y * s->uvlinesize + x * 4,
                             dst[2] + 4 * y * s->uvlinesize + x * 4, ref,
                             &uvmv, 4 * x + x_off, 4 * y + y_off, 4, 4,
                             width, height, s->uvlinesize,
                             s->put_pixels_tab[2]);
           }
       }
       break;
   }
   case VP8_SPLITMVMODE_16x8:
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   0, 0, 16, 8, width, height, &bmv[0]);
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   0, 8, 16, 8, width, height, &bmv[1]);
       break;
   case VP8_SPLITMVMODE_8x16:
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   0, 0, 8, 16, width, height, &bmv[0]);
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   8, 0, 8, 16, width, height, &bmv[1]);
       break;
   case VP8_SPLITMVMODE_8x8:
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   0, 0, 8, 8, width, height, &bmv[0]);
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   8, 0, 8, 8, width, height, &bmv[1]);
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   0, 8, 8, 8, width, height, &bmv[2]);
       vp8_mc_part(s, td, dst, ref, x_off, y_off,
                   8, 8, 8, 8, width, height, &bmv[3]);
       break;
   }
}

static av_always_inline
void idct_mb(VP8Context *s, VP8ThreadData *td, uint8_t *const dst[3],
            const VP8Macroblock *mb)
{
   int x, y, ch;

   if (mb->mode != MODE_I4x4) {
       uint8_t *y_dst = dst[0];
       for (y = 0; y < 4; y++) {
           uint32_t nnz4 = AV_RL32(td->non_zero_count_cache[y]);
           if (nnz4) {
               if (nnz4 & ~0x01010101) {
                   for (x = 0; x < 4; x++) {
                       if ((uint8_t) nnz4 == 1)
                           s->vp8dsp.vp8_idct_dc_add(y_dst + 4 * x,
                                                     td->block[y][x],
                                                     s->linesize);
                       else if ((uint8_t) nnz4 > 1)
                           s->vp8dsp.vp8_idct_add(y_dst + 4 * x,
                                                  td->block[y][x],
                                                  s->linesize);
                       nnz4 >>= 8;
                       if (!nnz4)
                           break;
                   }
               } else {
                   s->vp8dsp.vp8_idct_dc_add4y(y_dst, td->block[y], s->linesize);
               }
           }
           y_dst += 4 * s->linesize;
       }
   }

   for (ch = 0; ch < 2; ch++) {
       uint32_t nnz4 = AV_RL32(td->non_zero_count_cache[4 + ch]);
       if (nnz4) {
           uint8_t *ch_dst = dst[1 + ch];
           if (nnz4 & ~0x01010101) {
               for (y = 0; y < 2; y++) {
                   for (x = 0; x < 2; x++) {
                       if ((uint8_t) nnz4 == 1)
                           s->vp8dsp.vp8_idct_dc_add(ch_dst + 4 * x,
                                                     td->block[4 + ch][(y << 1) + x],
                                                     s->uvlinesize);
                       else if ((uint8_t) nnz4 > 1)
                           s->vp8dsp.vp8_idct_add(ch_dst + 4 * x,
                                                  td->block[4 + ch][(y << 1) + x],
                                                  s->uvlinesize);
                       nnz4 >>= 8;
                       if (!nnz4)
                           goto chroma_idct_end;
                   }
                   ch_dst += 4 * s->uvlinesize;
               }
           } else {
               s->vp8dsp.vp8_idct_dc_add4uv(ch_dst, td->block[4 + ch], s->uvlinesize);
           }
       }
chroma_idct_end:
       ;
   }
}

static av_always_inline
void filter_level_for_mb(const VP8Context *s, const VP8Macroblock *mb,
                        VP8FilterStrength *f, int is_vp7)
{
   int interior_limit, filter_level;

   if (s->segmentation.enabled) {
       filter_level = s->segmentation.filter_level[mb->segment];
       if (!s->segmentation.absolute_vals)
           filter_level += s->filter.level;
   } else
       filter_level = s->filter.level;

   if (s->lf_delta.enabled) {
       filter_level += s->lf_delta.ref[mb->ref_frame];
       filter_level += s->lf_delta.mode[mb->mode];
   }

   filter_level = av_clip_uintp2(filter_level, 6);

   interior_limit = filter_level;
   if (s->filter.sharpness) {
       interior_limit >>= (s->filter.sharpness + 3) >> 2;
       interior_limit = FFMIN(interior_limit, 9 - s->filter.sharpness);
   }
   interior_limit = FFMAX(interior_limit, 1);

   f->filter_level = filter_level;
   f->inner_limit = interior_limit;
   f->inner_filter = is_vp7 || !mb->skip || mb->mode == MODE_I4x4 ||
                     mb->mode == VP8_MVMODE_SPLIT;
}

static av_always_inline
void filter_mb(const VP8Context *s, uint8_t *const dst[3], const VP8FilterStrength *f,
              int mb_x, int mb_y, int is_vp7)
{
   int mbedge_lim, bedge_lim_y, bedge_lim_uv, hev_thresh;
   int filter_level = f->filter_level;
   int inner_limit = f->inner_limit;
   int inner_filter = f->inner_filter;
   ptrdiff_t linesize   = s->linesize;
   ptrdiff_t uvlinesize = s->uvlinesize;
   static const uint8_t hev_thresh_lut[2][64] = {
       { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1,
         2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
         3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
         3, 3, 3, 3 },
       { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1,
         1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
         2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
         2, 2, 2, 2 }
   };

   if (!filter_level)
       return;

   if (is_vp7) {
       bedge_lim_y  = filter_level;
       bedge_lim_uv = filter_level * 2;
       mbedge_lim   = filter_level + 2;
   } else {
       bedge_lim_y  =
       bedge_lim_uv = filter_level * 2 + inner_limit;
       mbedge_lim   = bedge_lim_y + 4;
   }

   hev_thresh = hev_thresh_lut[s->keyframe][filter_level];

   if (mb_x) {
       s->vp8dsp.vp8_h_loop_filter16y(dst[0], linesize,
                                      mbedge_lim, inner_limit, hev_thresh);
       s->vp8dsp.vp8_h_loop_filter8uv(dst[1], dst[2], uvlinesize,
                                      mbedge_lim, inner_limit, hev_thresh);
   }

#define H_LOOP_FILTER_16Y_INNER(cond)                                         \
   if (cond && inner_filter) {                                               \
       s->vp8dsp.vp8_h_loop_filter16y_inner(dst[0] +  4, linesize,           \
                                            bedge_lim_y, inner_limit,        \
                                            hev_thresh);                     \
       s->vp8dsp.vp8_h_loop_filter16y_inner(dst[0] +  8, linesize,           \
                                            bedge_lim_y, inner_limit,        \
                                            hev_thresh);                     \
       s->vp8dsp.vp8_h_loop_filter16y_inner(dst[0] + 12, linesize,           \
                                            bedge_lim_y, inner_limit,        \
                                            hev_thresh);                     \
       s->vp8dsp.vp8_h_loop_filter8uv_inner(dst[1] +  4, dst[2] + 4,         \
                                            uvlinesize,  bedge_lim_uv,       \
                                            inner_limit, hev_thresh);        \
   }

   H_LOOP_FILTER_16Y_INNER(!is_vp7)

   if (mb_y) {
       s->vp8dsp.vp8_v_loop_filter16y(dst[0], linesize,
                                      mbedge_lim, inner_limit, hev_thresh);
       s->vp8dsp.vp8_v_loop_filter8uv(dst[1], dst[2], uvlinesize,
                                      mbedge_lim, inner_limit, hev_thresh);
   }

   if (inner_filter) {
       s->vp8dsp.vp8_v_loop_filter16y_inner(dst[0] +  4 * linesize,
                                            linesize, bedge_lim_y,
                                            inner_limit, hev_thresh);
       s->vp8dsp.vp8_v_loop_filter16y_inner(dst[0] +  8 * linesize,
                                            linesize, bedge_lim_y,
                                            inner_limit, hev_thresh);
       s->vp8dsp.vp8_v_loop_filter16y_inner(dst[0] + 12 * linesize,
                                            linesize, bedge_lim_y,
                                            inner_limit, hev_thresh);
       s->vp8dsp.vp8_v_loop_filter8uv_inner(dst[1] +  4 * uvlinesize,
                                            dst[2] +  4 * uvlinesize,
                                            uvlinesize, bedge_lim_uv,
                                            inner_limit, hev_thresh);
   }

   H_LOOP_FILTER_16Y_INNER(is_vp7)
}

static av_always_inline
void filter_mb_simple(const VP8Context *s, uint8_t *dst, const VP8FilterStrength *f,
                     int mb_x, int mb_y)
{
   int mbedge_lim, bedge_lim;
   int filter_level = f->filter_level;
   int inner_limit  = f->inner_limit;
   int inner_filter = f->inner_filter;
   ptrdiff_t linesize = s->linesize;

   if (!filter_level)
       return;

   bedge_lim  = 2 * filter_level + inner_limit;
   mbedge_lim = bedge_lim + 4;

   if (mb_x)
       s->vp8dsp.vp8_h_loop_filter_simple(dst, linesize, mbedge_lim);
   if (inner_filter) {
       s->vp8dsp.vp8_h_loop_filter_simple(dst +  4, linesize, bedge_lim);
       s->vp8dsp.vp8_h_loop_filter_simple(dst +  8, linesize, bedge_lim);
       s->vp8dsp.vp8_h_loop_filter_simple(dst + 12, linesize, bedge_lim);
   }

   if (mb_y)
       s->vp8dsp.vp8_v_loop_filter_simple(dst, linesize, mbedge_lim);
   if (inner_filter) {
       s->vp8dsp.vp8_v_loop_filter_simple(dst +  4 * linesize, linesize, bedge_lim);
       s->vp8dsp.vp8_v_loop_filter_simple(dst +  8 * linesize, linesize, bedge_lim);
       s->vp8dsp.vp8_v_loop_filter_simple(dst + 12 * linesize, linesize, bedge_lim);
   }
}

#define MARGIN (16 << 2)
static av_always_inline
int vp78_decode_mv_mb_modes(AVCodecContext *avctx, VP8Frame *curframe,
                           const VP8Frame *prev_frame, int is_vp7)
{
   VP8Context *s = avctx->priv_data;
   int mb_x, mb_y;

   s->mv_bounds.mv_min.y = -MARGIN;
   s->mv_bounds.mv_max.y = ((s->mb_height - 1) << 6) + MARGIN;
   for (mb_y = 0; mb_y < s->mb_height; mb_y++) {
       VP8Macroblock *mb = s->macroblocks_base +
                           ((s->mb_width + 1) * (mb_y + 1) + 1);
       int mb_xy = mb_y * s->mb_width;

       AV_WN32A(s->intra4x4_pred_mode_left, DC_PRED * 0x01010101);

       s->mv_bounds.mv_min.x = -MARGIN;
       s->mv_bounds.mv_max.x = ((s->mb_width - 1) << 6) + MARGIN;

       for (mb_x = 0; mb_x < s->mb_width; mb_x++, mb_xy++, mb++) {
           if (vpx_rac_is_end(&s->c)) {
               return AVERROR_INVALIDDATA;
           }
           if (mb_y == 0)
               AV_WN32A((mb - s->mb_width - 1)->intra4x4_pred_mode_top,
                        DC_PRED * 0x01010101);
           decode_mb_mode(s, &s->mv_bounds, mb, mb_x, mb_y, curframe->seg_map + mb_xy,
                          prev_frame && prev_frame->seg_map ?
                          prev_frame->seg_map + mb_xy : NULL, 1, is_vp7);
           s->mv_bounds.mv_min.x -= 64;
           s->mv_bounds.mv_max.x -= 64;
       }
       s->mv_bounds.mv_min.y -= 64;
       s->mv_bounds.mv_max.y -= 64;
   }
   return 0;
}

static int vp7_decode_mv_mb_modes(AVCodecContext *avctx, VP8Frame *cur_frame,
                                 const VP8Frame *prev_frame)
{
   return vp78_decode_mv_mb_modes(avctx, cur_frame, prev_frame, IS_VP7);
}

static int vp8_decode_mv_mb_modes(AVCodecContext *avctx, VP8Frame *cur_frame,
                                 const VP8Frame *prev_frame)
{
   return vp78_decode_mv_mb_modes(avctx, cur_frame, prev_frame, IS_VP8);
}

#if HAVE_THREADS
#define check_thread_pos(td, otd, mb_x_check, mb_y_check)                     \
   do {                                                                      \
       int tmp = (mb_y_check << 16) | (mb_x_check & 0xFFFF);                 \
       if (atomic_load(&otd->thread_mb_pos) < tmp) {                         \
           pthread_mutex_lock(&otd->lock);                                   \
           atomic_store(&td->wait_mb_pos, tmp);                              \
           do {                                                              \
               if (atomic_load(&otd->thread_mb_pos) >= tmp)                  \
                   break;                                                    \
               pthread_cond_wait(&otd->cond, &otd->lock);                    \
           } while (1);                                                      \
           atomic_store(&td->wait_mb_pos, INT_MAX);                          \
           pthread_mutex_unlock(&otd->lock);                                 \
       }                                                                     \
   } while (0)

#define update_pos(td, mb_y, mb_x)                                            \
   do {                                                                      \
       int pos              = (mb_y << 16) | (mb_x & 0xFFFF);                \
       int sliced_threading = (avctx->active_thread_type == FF_THREAD_SLICE) && \
                              (num_jobs > 1);                                \
       int is_null          = !next_td || !prev_td;                          \
       int pos_check        = (is_null) ? 1 :                                \
           (next_td != td && pos >= atomic_load(&next_td->wait_mb_pos)) ||   \
           (prev_td != td && pos >= atomic_load(&prev_td->wait_mb_pos));     \
       atomic_store(&td->thread_mb_pos, pos);                                \
       if (sliced_threading && pos_check) {                                  \
           pthread_mutex_lock(&td->lock);                                    \
           pthread_cond_broadcast(&td->cond);                                \
           pthread_mutex_unlock(&td->lock);                                  \
       }                                                                     \
   } while (0)
#else
#define check_thread_pos(td, otd, mb_x_check, mb_y_check) while(0)
#define update_pos(td, mb_y, mb_x) while(0)
#endif

static av_always_inline int decode_mb_row_no_filter(AVCodecContext *avctx, void *tdata,
                                       int jobnr, int threadnr, int is_vp7)
{
   VP8Context *s = avctx->priv_data;
   VP8ThreadData *prev_td, *next_td, *td = &s->thread_data[threadnr];
   int mb_y = atomic_load(&td->thread_mb_pos) >> 16;
   int mb_x, mb_xy = mb_y * s->mb_width;
   int num_jobs = s->num_jobs;
   const VP8Frame *prev_frame = s->prev_frame;
   VP8Frame *curframe = s->curframe;
   VPXRangeCoder *coeff_c  = &s->coeff_partition[mb_y & (s->num_coeff_partitions - 1)];

   VP8Macroblock *mb;
   uint8_t *dst[3] = {
       curframe->tf.f->data[0] + 16 * mb_y * s->linesize,
       curframe->tf.f->data[1] +  8 * mb_y * s->uvlinesize,
       curframe->tf.f->data[2] +  8 * mb_y * s->uvlinesize
   };

   if (vpx_rac_is_end(&s->c))
        return AVERROR_INVALIDDATA;

   if (mb_y == 0)
       prev_td = td;
   else
       prev_td = &s->thread_data[(jobnr + num_jobs - 1) % num_jobs];
   if (mb_y == s->mb_height - 1)
       next_td = td;
   else
       next_td = &s->thread_data[(jobnr + 1) % num_jobs];
   if (s->mb_layout == 1)
       mb = s->macroblocks_base + ((s->mb_width + 1) * (mb_y + 1) + 1);
   else {
       // Make sure the previous frame has read its segmentation map,
       // if we re-use the same map.
       if (prev_frame && s->segmentation.enabled &&
           !s->segmentation.update_map)
           ff_progress_frame_await(&prev_frame->tf, mb_y);
       mb = s->macroblocks + (s->mb_height - mb_y - 1) * 2;
       memset(mb - 1, 0, sizeof(*mb)); // zero left macroblock
       AV_WN32A(s->intra4x4_pred_mode_left, DC_PRED * 0x01010101);
   }

   if (!is_vp7 || mb_y == 0)
       memset(td->left_nnz, 0, sizeof(td->left_nnz));

   td->mv_bounds.mv_min.x = -MARGIN;
   td->mv_bounds.mv_max.x = ((s->mb_width - 1) << 6) + MARGIN;

   for (mb_x = 0; mb_x < s->mb_width; mb_x++, mb_xy++, mb++) {
       if (vpx_rac_is_end(&s->c))
           return AVERROR_INVALIDDATA;
       // Wait for previous thread to read mb_x+2, and reach mb_y-1.
       if (prev_td != td) {
           if (threadnr != 0) {
               check_thread_pos(td, prev_td,
                                mb_x + (is_vp7 ? 2 : 1),
                                mb_y - (is_vp7 ? 2 : 1));
           } else {
               check_thread_pos(td, prev_td,
                                mb_x + (is_vp7 ? 2 : 1) + s->mb_width + 3,
                                mb_y - (is_vp7 ? 2 : 1));
           }
       }

       s->vdsp.prefetch(dst[0] + (mb_x & 3) * 4 * s->linesize + 64,
                        s->linesize, 4);
       s->vdsp.prefetch(dst[1] + (mb_x & 7) * s->uvlinesize + 64,
                        dst[2] - dst[1], 2);

       if (!s->mb_layout)
           decode_mb_mode(s, &td->mv_bounds, mb, mb_x, mb_y, curframe->seg_map + mb_xy,
                          prev_frame && prev_frame->seg_map ?
                          prev_frame->seg_map + mb_xy : NULL, 0, is_vp7);

       prefetch_motion(s, mb, mb_x, mb_y, mb_xy, VP8_FRAME_PREVIOUS);

       if (!mb->skip) {
           if (vpx_rac_is_end(coeff_c))
               return AVERROR_INVALIDDATA;
           decode_mb_coeffs(s, td, coeff_c, mb, s->top_nnz[mb_x], td->left_nnz, is_vp7);
       }

       if (mb->mode <= MODE_I4x4)
           intra_predict(s, td, dst, mb, mb_x, mb_y, is_vp7);
       else
           inter_predict(s, td, dst, mb, mb_x, mb_y);

       prefetch_motion(s, mb, mb_x, mb_y, mb_xy, VP8_FRAME_GOLDEN);

       if (!mb->skip) {
           idct_mb(s, td, dst, mb);
       } else {
           AV_ZERO64(td->left_nnz);
           AV_WN64(s->top_nnz[mb_x], 0);   // array of 9, so unaligned

           /* Reset DC block predictors if they would exist
            * if the mb had coefficients */
           if (mb->mode != MODE_I4x4 && mb->mode != VP8_MVMODE_SPLIT) {
               td->left_nnz[8]     = 0;
               s->top_nnz[mb_x][8] = 0;
           }
       }

       if (s->deblock_filter)
           filter_level_for_mb(s, mb, &td->filter_strength[mb_x], is_vp7);

       if (s->deblock_filter && num_jobs != 1 && threadnr == num_jobs - 1) {
           if (s->filter.simple)
               backup_mb_border(s->top_border[mb_x + 1], dst[0],
                                NULL, NULL, s->linesize, 0, 1);
           else
               backup_mb_border(s->top_border[mb_x + 1], dst[0],
                                dst[1], dst[2], s->linesize, s->uvlinesize, 0);
       }

       prefetch_motion(s, mb, mb_x, mb_y, mb_xy, VP8_FRAME_ALTREF);

       dst[0]      += 16;
       dst[1]      += 8;
       dst[2]      += 8;
       td->mv_bounds.mv_min.x -= 64;
       td->mv_bounds.mv_max.x -= 64;

       if (mb_x == s->mb_width + 1) {
           update_pos(td, mb_y, s->mb_width + 3);
       } else {
           update_pos(td, mb_y, mb_x);
       }
   }
   return 0;
}

static int vp7_decode_mb_row_no_filter(AVCodecContext *avctx, void *tdata,
                                       int jobnr, int threadnr)
{
   return decode_mb_row_no_filter(avctx, tdata, jobnr, threadnr, 1);
}

static int vp8_decode_mb_row_no_filter(AVCodecContext *avctx, void *tdata,
                                       int jobnr, int threadnr)
{
   return decode_mb_row_no_filter(avctx, tdata, jobnr, threadnr, 0);
}

static av_always_inline void filter_mb_row(AVCodecContext *avctx, void *tdata,
                             int jobnr, int threadnr, int is_vp7)
{
   VP8Context *s = avctx->priv_data;
   VP8ThreadData *td = &s->thread_data[threadnr];
   int mb_x, mb_y = atomic_load(&td->thread_mb_pos) >> 16, num_jobs = s->num_jobs;
   AVFrame *curframe = s->curframe->tf.f;
   VP8Macroblock *mb;
   VP8ThreadData *prev_td, *next_td;
   uint8_t *dst[3] = {
       curframe->data[0] + 16 * mb_y * s->linesize,
       curframe->data[1] +  8 * mb_y * s->uvlinesize,
       curframe->data[2] +  8 * mb_y * s->uvlinesize
   };

   if (s->mb_layout == 1)
       mb = s->macroblocks_base + ((s->mb_width + 1) * (mb_y + 1) + 1);
   else
       mb = s->macroblocks + (s->mb_height - mb_y - 1) * 2;

   if (mb_y == 0)
       prev_td = td;
   else
       prev_td = &s->thread_data[(jobnr + num_jobs - 1) % num_jobs];
   if (mb_y == s->mb_height - 1)
       next_td = td;
   else
       next_td = &s->thread_data[(jobnr + 1) % num_jobs];

   for (mb_x = 0; mb_x < s->mb_width; mb_x++, mb++) {
       const VP8FilterStrength *f = &td->filter_strength[mb_x];
       if (prev_td != td)
           check_thread_pos(td, prev_td,
                            (mb_x + 1) + (s->mb_width + 3), mb_y - 1);
       if (next_td != td)
           if (next_td != &s->thread_data[0])
               check_thread_pos(td, next_td, mb_x + 1, mb_y + 1);

       if (num_jobs == 1) {
           if (s->filter.simple)
               backup_mb_border(s->top_border[mb_x + 1], dst[0],
                                NULL, NULL, s->linesize, 0, 1);
           else
               backup_mb_border(s->top_border[mb_x + 1], dst[0],
                                dst[1], dst[2], s->linesize, s->uvlinesize, 0);
       }

       if (s->filter.simple)
           filter_mb_simple(s, dst[0], f, mb_x, mb_y);
       else
           filter_mb(s, dst, f, mb_x, mb_y, is_vp7);
       dst[0] += 16;
       dst[1] += 8;
       dst[2] += 8;

       update_pos(td, mb_y, (s->mb_width + 3) + mb_x);
   }
}

static void vp7_filter_mb_row(AVCodecContext *avctx, void *tdata,
                             int jobnr, int threadnr)
{
   filter_mb_row(avctx, tdata, jobnr, threadnr, 1);
}

static void vp8_filter_mb_row(AVCodecContext *avctx, void *tdata,
                             int jobnr, int threadnr)
{
   filter_mb_row(avctx, tdata, jobnr, threadnr, 0);
}

static av_always_inline
int vp78_decode_mb_row_sliced(AVCodecContext *avctx, void *tdata, int jobnr,
                             int threadnr, int is_vp7)
{
   const VP8Context *s = avctx->priv_data;
   VP8ThreadData *td = &s->thread_data[jobnr];
   VP8ThreadData *next_td = NULL, *prev_td = NULL;
   VP8Frame *curframe = s->curframe;
   int mb_y, num_jobs = s->num_jobs;
   int ret;

   td->thread_nr = threadnr;
   td->mv_bounds.mv_min.y   = -MARGIN - 64 * threadnr;
   td->mv_bounds.mv_max.y   = ((s->mb_height - 1) << 6) + MARGIN - 64 * threadnr;
   for (mb_y = jobnr; mb_y < s->mb_height; mb_y += num_jobs) {
       atomic_store(&td->thread_mb_pos, mb_y << 16);
       ret = s->decode_mb_row_no_filter(avctx, tdata, jobnr, threadnr);
       if (ret < 0) {
           update_pos(td, s->mb_height, INT_MAX & 0xFFFF);
           return ret;
       }
       if (s->deblock_filter)
           s->filter_mb_row(avctx, tdata, jobnr, threadnr);
       update_pos(td, mb_y, INT_MAX & 0xFFFF);

       td->mv_bounds.mv_min.y -= 64 * num_jobs;
       td->mv_bounds.mv_max.y -= 64 * num_jobs;

       if (avctx->active_thread_type == FF_THREAD_FRAME)
           ff_progress_frame_report(&curframe->tf, mb_y);
   }

   return 0;
}

static int vp7_decode_mb_row_sliced(AVCodecContext *avctx, void *tdata,
                                   int jobnr, int threadnr)
{
   return vp78_decode_mb_row_sliced(avctx, tdata, jobnr, threadnr, IS_VP7);
}

static int vp8_decode_mb_row_sliced(AVCodecContext *avctx, void *tdata,
                                   int jobnr, int threadnr)
{
   return vp78_decode_mb_row_sliced(avctx, tdata, jobnr, threadnr, IS_VP8);
}

static av_always_inline
int vp78_decode_frame(AVCodecContext *avctx, AVFrame *rframe, int *got_frame,
                     const AVPacket *avpkt, int is_vp7)
{
   VP8Context *s = avctx->priv_data;
   int ret, i, referenced, num_jobs;
   enum AVDiscard skip_thresh;
   VP8Frame *av_uninit(curframe), *prev_frame;

   if (is_vp7)
       ret = vp7_decode_frame_header(s, avpkt->data, avpkt->size);
   else
       ret = vp8_decode_frame_header(s, avpkt->data, avpkt->size);

   if (ret < 0)
       goto err;

   if (!is_vp7 && s->actually_webp) {
       // VP8 in WebP is supposed to be intra-only. Enforce this here
       // to ensure that output is reproducible with frame-threading.
       if (!s->keyframe)
           return AVERROR_INVALIDDATA;
       // avctx->pix_fmt already set in caller.
   } else if (!is_vp7 && s->pix_fmt == AV_PIX_FMT_NONE) {
       s->pix_fmt = get_pixel_format(s);
       if (s->pix_fmt < 0) {
           ret = AVERROR(EINVAL);
           goto err;
       }
       avctx->pix_fmt = s->pix_fmt;
   }

   prev_frame = s->framep[VP8_FRAME_CURRENT];

   referenced = s->update_last || s->update_golden == VP8_FRAME_CURRENT ||
                s->update_altref == VP8_FRAME_CURRENT;

   skip_thresh = !referenced ? AVDISCARD_NONREF
                             : !s->keyframe ? AVDISCARD_NONKEY
                                            : AVDISCARD_ALL;

   if (avctx->skip_frame >= skip_thresh) {
       s->invisible = 1;
       memcpy(&s->next_framep[0], &s->framep[0], sizeof(s->framep[0]) * 4);
       goto skip_decode;
   }
   s->deblock_filter = s->filter.level && avctx->skip_loop_filter < skip_thresh;

   // release no longer referenced frames
   for (i = 0; i < 5; i++)
       if (s->frames[i].tf.f &&
           &s->frames[i] != prev_frame &&
           &s->frames[i] != s->framep[VP8_FRAME_PREVIOUS] &&
           &s->frames[i] != s->framep[VP8_FRAME_GOLDEN]   &&
           &s->frames[i] != s->framep[VP8_FRAME_ALTREF])
           vp8_release_frame(&s->frames[i]);

   curframe = s->framep[VP8_FRAME_CURRENT] = vp8_find_free_buffer(s);

   if (!s->colorspace)
       avctx->colorspace = AVCOL_SPC_BT470BG;
   if (s->fullrange)
       avctx->color_range = AVCOL_RANGE_JPEG;
   else
       avctx->color_range = AVCOL_RANGE_MPEG;

   /* Given that arithmetic probabilities are updated every frame, it's quite
    * likely that the values we have on a random interframe are complete
    * junk if we didn't start decode on a keyframe. So just don't display
    * anything rather than junk. */
   if (!s->keyframe && (!s->framep[VP8_FRAME_PREVIOUS] ||
                        !s->framep[VP8_FRAME_GOLDEN]   ||
                        !s->framep[VP8_FRAME_ALTREF])) {
       av_log(avctx, AV_LOG_WARNING,
              "Discarding interframe without a prior keyframe!\n");
       ret = AVERROR_INVALIDDATA;
       goto err;
   }

   if ((ret = vp8_alloc_frame(s, curframe, referenced)) < 0)
       goto err;
   if (s->keyframe)
       curframe->tf.f->flags |= AV_FRAME_FLAG_KEY;
   else
       curframe->tf.f->flags &= ~AV_FRAME_FLAG_KEY;
   curframe->tf.f->pict_type = s->keyframe ? AV_PICTURE_TYPE_I
                                           : AV_PICTURE_TYPE_P;

   // check if golden and altref are swapped
   if (s->update_altref != VP8_FRAME_NONE)
       s->next_framep[VP8_FRAME_ALTREF] = s->framep[s->update_altref];
   else
       s->next_framep[VP8_FRAME_ALTREF] = s->framep[VP8_FRAME_ALTREF];

   if (s->update_golden != VP8_FRAME_NONE)
       s->next_framep[VP8_FRAME_GOLDEN] = s->framep[s->update_golden];
   else
       s->next_framep[VP8_FRAME_GOLDEN] = s->framep[VP8_FRAME_GOLDEN];

   if (s->update_last)
       s->next_framep[VP8_FRAME_PREVIOUS] = curframe;
   else
       s->next_framep[VP8_FRAME_PREVIOUS] = s->framep[VP8_FRAME_PREVIOUS];

   s->next_framep[VP8_FRAME_CURRENT] = curframe;

   if (!is_vp7 && !s->actually_webp)
       ff_thread_finish_setup(avctx);

   if (avctx->hwaccel) {
       const FFHWAccel *hwaccel = ffhwaccel(avctx->hwaccel);
       ret = hwaccel->start_frame(avctx, avpkt->data, avpkt->size);
       if (ret < 0)
           goto err;

       ret = hwaccel->decode_slice(avctx, avpkt->data, avpkt->size);
       if (ret < 0)
           goto err;

       ret = hwaccel->end_frame(avctx);
       if (ret < 0)
           goto err;

   } else {
       s->linesize   = curframe->tf.f->linesize[0];
       s->uvlinesize = curframe->tf.f->linesize[1];

       memset(s->top_nnz, 0, s->mb_width * sizeof(*s->top_nnz));
       /* Zero macroblock structures for top/top-left prediction
        * from outside the frame. */
       if (!s->mb_layout)
           memset(s->macroblocks + s->mb_height * 2 - 1, 0,
                  (s->mb_width + 1) * sizeof(*s->macroblocks));
       if (!s->mb_layout && s->keyframe)
           memset(s->intra4x4_pred_mode_top, DC_PRED, s->mb_width * 4);

       memset(s->ref_count, 0, sizeof(s->ref_count));

       if (s->mb_layout == 1) {
           // Make sure the previous frame has read its segmentation map,
           // if we re-use the same map.
           if (prev_frame && s->segmentation.enabled &&
               !s->segmentation.update_map)
               ff_progress_frame_await(&prev_frame->tf, 1);
           if (is_vp7)
               ret = vp7_decode_mv_mb_modes(avctx, curframe, prev_frame);
           else
               ret = vp8_decode_mv_mb_modes(avctx, curframe, prev_frame);
           if (ret < 0)
               goto err;
       }

       if (avctx->active_thread_type == FF_THREAD_FRAME)
           num_jobs = 1;
       else
           num_jobs = FFMIN(s->num_coeff_partitions, avctx->thread_count);
       s->num_jobs   = num_jobs;
       s->curframe   = curframe;
       s->prev_frame = prev_frame;
       s->mv_bounds.mv_min.y   = -MARGIN;
       s->mv_bounds.mv_max.y   = ((s->mb_height - 1) << 6) + MARGIN;
       for (i = 0; i < MAX_THREADS; i++) {
           VP8ThreadData *td = &s->thread_data[i];
           atomic_init(&td->thread_mb_pos, 0);
           atomic_init(&td->wait_mb_pos, INT_MAX);
       }
       if (is_vp7)
           avctx->execute2(avctx, vp7_decode_mb_row_sliced, s->thread_data, NULL,
                           num_jobs);
       else
           avctx->execute2(avctx, vp8_decode_mb_row_sliced, s->thread_data, NULL,
                           num_jobs);
   }

   ff_progress_frame_report(&curframe->tf, INT_MAX);
   memcpy(&s->framep[0], &s->next_framep[0], sizeof(s->framep[0]) * 4);

skip_decode:
   // if future frames don't use the updated probabilities,
   // reset them to the values we saved
   if (!s->update_probabilities)
       s->prob[0] = s->prob[1];

   if (!s->invisible) {
       if ((ret = av_frame_ref(rframe, curframe->tf.f)) < 0)
           return ret;
       *got_frame = 1;
   }

   return avpkt->size;
err:
   memcpy(&s->next_framep[0], &s->framep[0], sizeof(s->framep[0]) * 4);
   return ret;
}

int ff_vp8_decode_frame(AVCodecContext *avctx, AVFrame *frame,
                       int *got_frame, AVPacket *avpkt)
{
   return vp78_decode_frame(avctx, frame, got_frame, avpkt, IS_VP8);
}

#if CONFIG_VP7_DECODER
static int vp7_decode_frame(AVCodecContext *avctx, AVFrame *frame,
                           int *got_frame, AVPacket *avpkt)
{
   return vp78_decode_frame(avctx, frame, got_frame, avpkt, IS_VP7);
}
#endif /* CONFIG_VP7_DECODER */

av_cold int ff_vp8_decode_free(AVCodecContext *avctx)
{
   vp8_decode_flush_impl(avctx, 1);

   return 0;
}

static av_always_inline
int vp78_decode_init(AVCodecContext *avctx, int is_vp7)
{
   VP8Context *s = avctx->priv_data;

   s->avctx = avctx;
   s->pix_fmt = AV_PIX_FMT_NONE;
   avctx->pix_fmt = AV_PIX_FMT_YUV420P;

   ff_videodsp_init(&s->vdsp, 8);

   ff_vp78dsp_init(&s->vp8dsp);
   if (CONFIG_VP7_DECODER && is_vp7) {
       ff_h264_pred_init(&s->hpc, AV_CODEC_ID_VP7, 8, 1);
       ff_vp7dsp_init(&s->vp8dsp);
       s->decode_mb_row_no_filter = vp7_decode_mb_row_no_filter;
       s->filter_mb_row           = vp7_filter_mb_row;
   } else if (CONFIG_VP8_DECODER && !is_vp7) {
       ff_h264_pred_init(&s->hpc, AV_CODEC_ID_VP8, 8, 1);
       ff_vp8dsp_init(&s->vp8dsp);
       s->decode_mb_row_no_filter = vp8_decode_mb_row_no_filter;
       s->filter_mb_row           = vp8_filter_mb_row;
   }

   /* does not change for VP8 */
   memcpy(s->prob[0].scan, ff_zigzag_scan, sizeof(s->prob[0].scan));

   return 0;
}

#if CONFIG_VP7_DECODER
static int vp7_decode_init(AVCodecContext *avctx)
{
   return vp78_decode_init(avctx, IS_VP7);
}
#endif /* CONFIG_VP7_DECODER */

av_cold int ff_vp8_decode_init(AVCodecContext *avctx)
{
   return vp78_decode_init(avctx, IS_VP8);
}

#if CONFIG_VP8_DECODER
#if HAVE_THREADS
static void vp8_replace_frame(VP8Frame *dst, const VP8Frame *src)
{
   ff_progress_frame_replace(&dst->tf, &src->tf);
   av_refstruct_replace(&dst->seg_map, src->seg_map);
   av_refstruct_replace(&dst->hwaccel_picture_private,
                         src->hwaccel_picture_private);
}

#define REBASE(pic) ((pic) ? (pic) - &s_src->frames[0] + &s->frames[0] : NULL)

static int vp8_decode_update_thread_context(AVCodecContext *dst,
                                           const AVCodecContext *src)
{
   VP8Context *s = dst->priv_data, *s_src = src->priv_data;

   if (s->macroblocks_base &&
       (s_src->mb_width != s->mb_width || s_src->mb_height != s->mb_height)) {
       free_buffers(s);
       s->mb_width  = s_src->mb_width;
       s->mb_height = s_src->mb_height;
   }

   s->pix_fmt      = s_src->pix_fmt;
   s->prob[0]      = s_src->prob[!s_src->update_probabilities];
   s->segmentation = s_src->segmentation;
   s->lf_delta     = s_src->lf_delta;
   memcpy(s->sign_bias, s_src->sign_bias, sizeof(s->sign_bias));

   for (int i = 0; i < FF_ARRAY_ELEMS(s_src->frames); i++)
       vp8_replace_frame(&s->frames[i], &s_src->frames[i]);

   s->framep[0] = REBASE(s_src->next_framep[0]);
   s->framep[1] = REBASE(s_src->next_framep[1]);
   s->framep[2] = REBASE(s_src->next_framep[2]);
   s->framep[3] = REBASE(s_src->next_framep[3]);

   return 0;
}
#endif /* HAVE_THREADS */
#endif /* CONFIG_VP8_DECODER */

#if CONFIG_VP7_DECODER
const FFCodec ff_vp7_decoder = {
   .p.name                = "vp7",
   CODEC_LONG_NAME("On2 VP7"),
   .p.type                = AVMEDIA_TYPE_VIDEO,
   .p.id                  = AV_CODEC_ID_VP7,
   .priv_data_size        = sizeof(VP8Context),
   .init                  = vp7_decode_init,
   .close                 = ff_vp8_decode_free,
   FF_CODEC_DECODE_CB(vp7_decode_frame),
   .p.capabilities        = AV_CODEC_CAP_DR1,
   .flush                 = vp8_decode_flush,
   .caps_internal         = FF_CODEC_CAP_USES_PROGRESSFRAMES,
};
#endif /* CONFIG_VP7_DECODER */

#if CONFIG_VP8_DECODER
const FFCodec ff_vp8_decoder = {
   .p.name                = "vp8",
   CODEC_LONG_NAME("On2 VP8"),
   .p.type                = AVMEDIA_TYPE_VIDEO,
   .p.id                  = AV_CODEC_ID_VP8,
   .priv_data_size        = sizeof(VP8Context),
   .init                  = ff_vp8_decode_init,
   .close                 = ff_vp8_decode_free,
   FF_CODEC_DECODE_CB(ff_vp8_decode_frame),
   .p.capabilities        = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS |
                            AV_CODEC_CAP_SLICE_THREADS,
   .caps_internal         = FF_CODEC_CAP_USES_PROGRESSFRAMES,
   .flush                 = vp8_decode_flush,
   UPDATE_THREAD_CONTEXT(vp8_decode_update_thread_context),
   .hw_configs            = (const AVCodecHWConfigInternal *const []) {
#if CONFIG_VP8_VAAPI_HWACCEL
                              HWACCEL_VAAPI(vp8),
#endif
#if CONFIG_VP8_NVDEC_HWACCEL
                              HWACCEL_NVDEC(vp8),
#endif
                              NULL
                          },
};
#endif /* CONFIG_VP7_DECODER */