yading@10: /*
yading@10:  * Copyright (C) 2006  Aurelien Jacobs <aurel@gnuage.org>
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * VP6 compatible video decoder
yading@10:  *
yading@10:  * The VP6F decoder accepts an optional 1 byte extradata. It is composed of:
yading@10:  *  - upper 4 bits: difference between encoded width and visible width
yading@10:  *  - lower 4 bits: difference between encoded height and visible height
yading@10:  */
yading@10: 
yading@10: #include <stdlib.h>
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "get_bits.h"
yading@10: #include "huffman.h"
yading@10: 
yading@10: #include "vp56.h"
yading@10: #include "vp56data.h"
yading@10: #include "vp6data.h"
yading@10: 
yading@10: #define VP6_MAX_HUFF_SIZE 12
yading@10: 
yading@10: static void vp6_parse_coeff(VP56Context *s);
yading@10: static void vp6_parse_coeff_huffman(VP56Context *s);
yading@10: 
yading@10: static int vp6_parse_header(VP56Context *s, const uint8_t *buf, int buf_size)
yading@10: {
yading@10:     VP56RangeCoder *c = &s->c;
yading@10:     int parse_filter_info = 0;
yading@10:     int coeff_offset = 0;
yading@10:     int vrt_shift = 0;
yading@10:     int sub_version;
yading@10:     int rows, cols;
yading@10:     int res = 0;
yading@10:     int separated_coeff = buf[0] & 1;
yading@10: 
yading@10:     s->frames[VP56_FRAME_CURRENT]->key_frame = !(buf[0] & 0x80);
yading@10:     ff_vp56_init_dequant(s, (buf[0] >> 1) & 0x3F);
yading@10: 
yading@10:     if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
yading@10:         sub_version = buf[1] >> 3;
yading@10:         if (sub_version > 8)
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         s->filter_header = buf[1] & 0x06;
yading@10:         if (buf[1] & 1) {
yading@10:             avpriv_report_missing_feature(s->avctx, "Interlacing");
yading@10:             return AVERROR_PATCHWELCOME;
yading@10:         }
yading@10:         if (separated_coeff || !s->filter_header) {
yading@10:             coeff_offset = AV_RB16(buf+2) - 2;
yading@10:             buf += 2;
yading@10:             buf_size -= 2;
yading@10:         }
yading@10: 
yading@10:         rows = buf[2];  /* number of stored macroblock rows */
yading@10:         cols = buf[3];  /* number of stored macroblock cols */
yading@10:         /* buf[4] is number of displayed macroblock rows */
yading@10:         /* buf[5] is number of displayed macroblock cols */
yading@10:         if (!rows || !cols) {
yading@10:             av_log(s->avctx, AV_LOG_ERROR, "Invalid size %dx%d\n", cols << 4, rows << 4);
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10: 
yading@10:         if (!s->macroblocks || /* first frame */
yading@10:             16*cols != s->avctx->coded_width ||
yading@10:             16*rows != s->avctx->coded_height) {
yading@10:             avcodec_set_dimensions(s->avctx, 16*cols, 16*rows);
yading@10:             if (s->avctx->extradata_size == 1) {
yading@10:                 s->avctx->width  -= s->avctx->extradata[0] >> 4;
yading@10:                 s->avctx->height -= s->avctx->extradata[0] & 0x0F;
yading@10:             }
yading@10:             res = VP56_SIZE_CHANGE;
yading@10:         }
yading@10: 
yading@10:         ff_vp56_init_range_decoder(c, buf+6, buf_size-6);
yading@10:         vp56_rac_gets(c, 2);
yading@10: 
yading@10:         parse_filter_info = s->filter_header;
yading@10:         if (sub_version < 8)
yading@10:             vrt_shift = 5;
yading@10:         s->sub_version = sub_version;
yading@10:         s->golden_frame = 0;
yading@10:     } else {
yading@10:         if (!s->sub_version || !s->avctx->coded_width || !s->avctx->coded_height)
yading@10:             return AVERROR_INVALIDDATA;
yading@10: 
yading@10:         if (separated_coeff || !s->filter_header) {
yading@10:             coeff_offset = AV_RB16(buf+1) - 2;
yading@10:             buf += 2;
yading@10:             buf_size -= 2;
yading@10:         }
yading@10:         ff_vp56_init_range_decoder(c, buf+1, buf_size-1);
yading@10: 
yading@10:         s->golden_frame = vp56_rac_get(c);
yading@10:         if (s->filter_header) {
yading@10:             s->deblock_filtering = vp56_rac_get(c);
yading@10:             if (s->deblock_filtering)
yading@10:                 vp56_rac_get(c);
yading@10:             if (s->sub_version > 7)
yading@10:                 parse_filter_info = vp56_rac_get(c);
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     if (parse_filter_info) {
yading@10:         if (vp56_rac_get(c)) {
yading@10:             s->filter_mode = 2;
yading@10:             s->sample_variance_threshold = vp56_rac_gets(c, 5) << vrt_shift;
yading@10:             s->max_vector_length = 2 << vp56_rac_gets(c, 3);
yading@10:         } else if (vp56_rac_get(c)) {
yading@10:             s->filter_mode = 1;
yading@10:         } else {
yading@10:             s->filter_mode = 0;
yading@10:         }
yading@10:         if (s->sub_version > 7)
yading@10:             s->filter_selection = vp56_rac_gets(c, 4);
yading@10:         else
yading@10:             s->filter_selection = 16;
yading@10:     }
yading@10: 
yading@10:     s->use_huffman = vp56_rac_get(c);
yading@10: 
yading@10:     s->parse_coeff = vp6_parse_coeff;
yading@10:     if (coeff_offset) {
yading@10:         buf      += coeff_offset;
yading@10:         buf_size -= coeff_offset;
yading@10:         if (buf_size < 0) {
yading@10:             if (s->frames[VP56_FRAME_CURRENT]->key_frame)
yading@10:                 avcodec_set_dimensions(s->avctx, 0, 0);
yading@10:             return AVERROR_INVALIDDATA;
yading@10:         }
yading@10:         if (s->use_huffman) {
yading@10:             s->parse_coeff = vp6_parse_coeff_huffman;
yading@10:             init_get_bits(&s->gb, buf, buf_size<<3);
yading@10:         } else {
yading@10:             ff_vp56_init_range_decoder(&s->cc, buf, buf_size);
yading@10:             s->ccp = &s->cc;
yading@10:         }
yading@10:     } else {
yading@10:         s->ccp = &s->c;
yading@10:     }
yading@10: 
yading@10:     return res;
yading@10: }
yading@10: 
yading@10: static void vp6_coeff_order_table_init(VP56Context *s)
yading@10: {
yading@10:     int i, pos, idx = 1;
yading@10: 
yading@10:     s->modelp->coeff_index_to_pos[0] = 0;
yading@10:     for (i=0; i<16; i++)
yading@10:         for (pos=1; pos<64; pos++)
yading@10:             if (s->modelp->coeff_reorder[pos] == i)
yading@10:                 s->modelp->coeff_index_to_pos[idx++] = pos;
yading@10: }
yading@10: 
yading@10: static void vp6_default_models_init(VP56Context *s)
yading@10: {
yading@10:     VP56Model *model = s->modelp;
yading@10: 
yading@10:     model->vector_dct[0] = 0xA2;
yading@10:     model->vector_dct[1] = 0xA4;
yading@10:     model->vector_sig[0] = 0x80;
yading@10:     model->vector_sig[1] = 0x80;
yading@10: 
yading@10:     memcpy(model->mb_types_stats, ff_vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
yading@10:     memcpy(model->vector_fdv, vp6_def_fdv_vector_model, sizeof(model->vector_fdv));
yading@10:     memcpy(model->vector_pdv, vp6_def_pdv_vector_model, sizeof(model->vector_pdv));
yading@10:     memcpy(model->coeff_runv, vp6_def_runv_coeff_model, sizeof(model->coeff_runv));
yading@10:     memcpy(model->coeff_reorder, vp6_def_coeff_reorder, sizeof(model->coeff_reorder));
yading@10: 
yading@10:     vp6_coeff_order_table_init(s);
yading@10: }
yading@10: 
yading@10: static void vp6_parse_vector_models(VP56Context *s)
yading@10: {
yading@10:     VP56RangeCoder *c = &s->c;
yading@10:     VP56Model *model = s->modelp;
yading@10:     int comp, node;
yading@10: 
yading@10:     for (comp=0; comp<2; comp++) {
yading@10:         if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][0]))
yading@10:             model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
yading@10:         if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][1]))
yading@10:             model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
yading@10:     }
yading@10: 
yading@10:     for (comp=0; comp<2; comp++)
yading@10:         for (node=0; node<7; node++)
yading@10:             if (vp56_rac_get_prob(c, vp6_pdv_pct[comp][node]))
yading@10:                 model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
yading@10: 
yading@10:     for (comp=0; comp<2; comp++)
yading@10:         for (node=0; node<8; node++)
yading@10:             if (vp56_rac_get_prob(c, vp6_fdv_pct[comp][node]))
yading@10:                 model->vector_fdv[comp][node] = vp56_rac_gets_nn(c, 7);
yading@10: }
yading@10: 
yading@10: /* nodes must ascend by count, but with descending symbol order */
yading@10: static int vp6_huff_cmp(const void *va, const void *vb)
yading@10: {
yading@10:     const Node *a = va, *b = vb;
yading@10:     return (a->count - b->count)*16 + (b->sym - a->sym);
yading@10: }
yading@10: 
yading@10: static int vp6_build_huff_tree(VP56Context *s, uint8_t coeff_model[],
yading@10:                                const uint8_t *map, unsigned size, VLC *vlc)
yading@10: {
yading@10:     Node nodes[2*VP6_MAX_HUFF_SIZE], *tmp = &nodes[size];
yading@10:     int a, b, i;
yading@10: 
yading@10:     /* first compute probabilities from model */
yading@10:     tmp[0].count = 256;
yading@10:     for (i=0; i<size-1; i++) {
yading@10:         a = tmp[i].count *        coeff_model[i]  >> 8;
yading@10:         b = tmp[i].count * (255 - coeff_model[i]) >> 8;
yading@10:         nodes[map[2*i  ]].count = a + !a;
yading@10:         nodes[map[2*i+1]].count = b + !b;
yading@10:     }
yading@10: 
yading@10:     ff_free_vlc(vlc);
yading@10:     /* then build the huffman tree according to probabilities */
yading@10:     return ff_huff_build_tree(s->avctx, vlc, size, nodes, vp6_huff_cmp,
yading@10:                               FF_HUFFMAN_FLAG_HNODE_FIRST);
yading@10: }
yading@10: 
yading@10: static int vp6_parse_coeff_models(VP56Context *s)
yading@10: {
yading@10:     VP56RangeCoder *c = &s->c;
yading@10:     VP56Model *model = s->modelp;
yading@10:     int def_prob[11];
yading@10:     int node, cg, ctx, pos;
yading@10:     int ct;    /* code type */
yading@10:     int pt;    /* plane type (0 for Y, 1 for U or V) */
yading@10: 
yading@10:     memset(def_prob, 0x80, sizeof(def_prob));
yading@10: 
yading@10:     for (pt=0; pt<2; pt++)
yading@10:         for (node=0; node<11; node++)
yading@10:             if (vp56_rac_get_prob(c, vp6_dccv_pct[pt][node])) {
yading@10:                 def_prob[node] = vp56_rac_gets_nn(c, 7);
yading@10:                 model->coeff_dccv[pt][node] = def_prob[node];
yading@10:             } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
yading@10:                 model->coeff_dccv[pt][node] = def_prob[node];
yading@10:             }
yading@10: 
yading@10:     if (vp56_rac_get(c)) {
yading@10:         for (pos=1; pos<64; pos++)
yading@10:             if (vp56_rac_get_prob(c, vp6_coeff_reorder_pct[pos]))
yading@10:                 model->coeff_reorder[pos] = vp56_rac_gets(c, 4);
yading@10:         vp6_coeff_order_table_init(s);
yading@10:     }
yading@10: 
yading@10:     for (cg=0; cg<2; cg++)
yading@10:         for (node=0; node<14; node++)
yading@10:             if (vp56_rac_get_prob(c, vp6_runv_pct[cg][node]))
yading@10:                 model->coeff_runv[cg][node] = vp56_rac_gets_nn(c, 7);
yading@10: 
yading@10:     for (ct=0; ct<3; ct++)
yading@10:         for (pt=0; pt<2; pt++)
yading@10:             for (cg=0; cg<6; cg++)
yading@10:                 for (node=0; node<11; node++)
yading@10:                     if (vp56_rac_get_prob(c, vp6_ract_pct[ct][pt][cg][node])) {
yading@10:                         def_prob[node] = vp56_rac_gets_nn(c, 7);
yading@10:                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
yading@10:                     } else if (s->frames[VP56_FRAME_CURRENT]->key_frame) {
yading@10:                         model->coeff_ract[pt][ct][cg][node] = def_prob[node];
yading@10:                     }
yading@10: 
yading@10:     if (s->use_huffman) {
yading@10:         for (pt=0; pt<2; pt++) {
yading@10:             if (vp6_build_huff_tree(s, model->coeff_dccv[pt],
yading@10:                                     vp6_huff_coeff_map, 12, &s->dccv_vlc[pt]))
yading@10:                 return -1;
yading@10:             if (vp6_build_huff_tree(s, model->coeff_runv[pt],
yading@10:                                     vp6_huff_run_map, 9, &s->runv_vlc[pt]))
yading@10:                 return -1;
yading@10:             for (ct=0; ct<3; ct++)
yading@10:                 for (cg = 0; cg < 6; cg++)
yading@10:                     if (vp6_build_huff_tree(s, model->coeff_ract[pt][ct][cg],
yading@10:                                             vp6_huff_coeff_map, 12,
yading@10:                                             &s->ract_vlc[pt][ct][cg]))
yading@10:                         return -1;
yading@10:         }
yading@10:         memset(s->nb_null, 0, sizeof(s->nb_null));
yading@10:     } else {
yading@10:     /* coeff_dcct is a linear combination of coeff_dccv */
yading@10:     for (pt=0; pt<2; pt++)
yading@10:         for (ctx=0; ctx<3; ctx++)
yading@10:             for (node=0; node<5; node++)
yading@10:                 model->coeff_dcct[pt][ctx][node] = av_clip(((model->coeff_dccv[pt][node] * vp6_dccv_lc[ctx][node][0] + 128) >> 8) + vp6_dccv_lc[ctx][node][1], 1, 255);
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static void vp6_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
yading@10: {
yading@10:     VP56RangeCoder *c = &s->c;
yading@10:     VP56Model *model = s->modelp;
yading@10:     int comp;
yading@10: 
yading@10:     *vect = (VP56mv) {0,0};
yading@10:     if (s->vector_candidate_pos < 2)
yading@10:         *vect = s->vector_candidate[0];
yading@10: 
yading@10:     for (comp=0; comp<2; comp++) {
yading@10:         int i, delta = 0;
yading@10: 
yading@10:         if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
yading@10:             static const uint8_t prob_order[] = {0, 1, 2, 7, 6, 5, 4};
yading@10:             for (i=0; i<sizeof(prob_order); i++) {
yading@10:                 int j = prob_order[i];
yading@10:                 delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][j])<<j;
yading@10:             }
yading@10:             if (delta & 0xF0)
yading@10:                 delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][3])<<3;
yading@10:             else
yading@10:                 delta |= 8;
yading@10:         } else {
yading@10:             delta = vp56_rac_get_tree(c, ff_vp56_pva_tree,
yading@10:                                       model->vector_pdv[comp]);
yading@10:         }
yading@10: 
yading@10:         if (delta && vp56_rac_get_prob(c, model->vector_sig[comp]))
yading@10:             delta = -delta;
yading@10: 
yading@10:         if (!comp)
yading@10:             vect->x += delta;
yading@10:         else
yading@10:             vect->y += delta;
yading@10:     }
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Read number of consecutive blocks with null DC or AC.
yading@10:  * This value is < 74.
yading@10:  */
yading@10: static unsigned vp6_get_nb_null(VP56Context *s)
yading@10: {
yading@10:     unsigned val = get_bits(&s->gb, 2);
yading@10:     if (val == 2)
yading@10:         val += get_bits(&s->gb, 2);
yading@10:     else if (val == 3) {
yading@10:         val = get_bits1(&s->gb) << 2;
yading@10:         val = 6+val + get_bits(&s->gb, 2+val);
yading@10:     }
yading@10:     return val;
yading@10: }
yading@10: 
yading@10: static void vp6_parse_coeff_huffman(VP56Context *s)
yading@10: {
yading@10:     VP56Model *model = s->modelp;
yading@10:     uint8_t *permute = s->idct_scantable;
yading@10:     VLC *vlc_coeff;
yading@10:     int coeff, sign, coeff_idx;
yading@10:     int b, cg, idx;
yading@10:     int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
yading@10: 
yading@10:     for (b=0; b<6; b++) {
yading@10:         int ct = 0;    /* code type */
yading@10:         if (b > 3) pt = 1;
yading@10:         vlc_coeff = &s->dccv_vlc[pt];
yading@10: 
yading@10:         for (coeff_idx = 0;;) {
yading@10:             int run = 1;
yading@10:             if (coeff_idx<2 && s->nb_null[coeff_idx][pt]) {
yading@10:                 s->nb_null[coeff_idx][pt]--;
yading@10:                 if (coeff_idx)
yading@10:                     break;
yading@10:             } else {
yading@10:                 if (get_bits_left(&s->gb) <= 0)
yading@10:                     return;
yading@10:                 coeff = get_vlc2(&s->gb, vlc_coeff->table, 9, 3);
yading@10:                 if (coeff == 0) {
yading@10:                     if (coeff_idx) {
yading@10:                         int pt = (coeff_idx >= 6);
yading@10:                         run += get_vlc2(&s->gb, s->runv_vlc[pt].table, 9, 3);
yading@10:                         if (run >= 9)
yading@10:                             run += get_bits(&s->gb, 6);
yading@10:                     } else
yading@10:                         s->nb_null[0][pt] = vp6_get_nb_null(s);
yading@10:                     ct = 0;
yading@10:                 } else if (coeff == 11) {  /* end of block */
yading@10:                     if (coeff_idx == 1)    /* first AC coeff ? */
yading@10:                         s->nb_null[1][pt] = vp6_get_nb_null(s);
yading@10:                     break;
yading@10:                 } else {
yading@10:                     int coeff2 = ff_vp56_coeff_bias[coeff];
yading@10:                     if (coeff > 4)
yading@10:                         coeff2 += get_bits(&s->gb, coeff <= 9 ? coeff - 4 : 11);
yading@10:                     ct = 1 + (coeff2 > 1);
yading@10:                     sign = get_bits1(&s->gb);
yading@10:                     coeff2 = (coeff2 ^ -sign) + sign;
yading@10:                     if (coeff_idx)
yading@10:                         coeff2 *= s->dequant_ac;
yading@10:                     idx = model->coeff_index_to_pos[coeff_idx];
yading@10:                     s->block_coeff[b][permute[idx]] = coeff2;
yading@10:                 }
yading@10:             }
yading@10:             coeff_idx+=run;
yading@10:             if (coeff_idx >= 64)
yading@10:                 break;
yading@10:             cg = FFMIN(vp6_coeff_groups[coeff_idx], 3);
yading@10:             vlc_coeff = &s->ract_vlc[pt][ct][cg];
yading@10:         }
yading@10:     }
yading@10: }
yading@10: 
yading@10: static void vp6_parse_coeff(VP56Context *s)
yading@10: {
yading@10:     VP56RangeCoder *c = s->ccp;
yading@10:     VP56Model *model = s->modelp;
yading@10:     uint8_t *permute = s->idct_scantable;
yading@10:     uint8_t *model1, *model2, *model3;
yading@10:     int coeff, sign, coeff_idx;
yading@10:     int b, i, cg, idx, ctx;
yading@10:     int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
yading@10: 
yading@10:     for (b=0; b<6; b++) {
yading@10:         int ct = 1;    /* code type */
yading@10:         int run = 1;
yading@10: 
yading@10:         if (b > 3) pt = 1;
yading@10: 
yading@10:         ctx = s->left_block[ff_vp56_b6to4[b]].not_null_dc
yading@10:               + s->above_blocks[s->above_block_idx[b]].not_null_dc;
yading@10:         model1 = model->coeff_dccv[pt];
yading@10:         model2 = model->coeff_dcct[pt][ctx];
yading@10: 
yading@10:         coeff_idx = 0;
yading@10:         for (;;) {
yading@10:             if ((coeff_idx>1 && ct==0) || vp56_rac_get_prob(c, model2[0])) {
yading@10:                 /* parse a coeff */
yading@10:                 if (vp56_rac_get_prob(c, model2[2])) {
yading@10:                     if (vp56_rac_get_prob(c, model2[3])) {
yading@10:                         idx = vp56_rac_get_tree(c, ff_vp56_pc_tree, model1);
yading@10:                         coeff = ff_vp56_coeff_bias[idx+5];
yading@10:                         for (i=ff_vp56_coeff_bit_length[idx]; i>=0; i--)
yading@10:                             coeff += vp56_rac_get_prob(c, ff_vp56_coeff_parse_table[idx][i]) << i;
yading@10:                     } else {
yading@10:                         if (vp56_rac_get_prob(c, model2[4]))
yading@10:                             coeff = 3 + vp56_rac_get_prob(c, model1[5]);
yading@10:                         else
yading@10:                             coeff = 2;
yading@10:                     }
yading@10:                     ct = 2;
yading@10:                 } else {
yading@10:                     ct = 1;
yading@10:                     coeff = 1;
yading@10:                 }
yading@10:                 sign = vp56_rac_get(c);
yading@10:                 coeff = (coeff ^ -sign) + sign;
yading@10:                 if (coeff_idx)
yading@10:                     coeff *= s->dequant_ac;
yading@10:                 idx = model->coeff_index_to_pos[coeff_idx];
yading@10:                 s->block_coeff[b][permute[idx]] = coeff;
yading@10:                 run = 1;
yading@10:             } else {
yading@10:                 /* parse a run */
yading@10:                 ct = 0;
yading@10:                 if (coeff_idx > 0) {
yading@10:                     if (!vp56_rac_get_prob(c, model2[1]))
yading@10:                         break;
yading@10: 
yading@10:                     model3 = model->coeff_runv[coeff_idx >= 6];
yading@10:                     run = vp56_rac_get_tree(c, vp6_pcr_tree, model3);
yading@10:                     if (!run)
yading@10:                         for (run=9, i=0; i<6; i++)
yading@10:                             run += vp56_rac_get_prob(c, model3[i+8]) << i;
yading@10:                 }
yading@10:             }
yading@10:             coeff_idx += run;
yading@10:             if (coeff_idx >= 64)
yading@10:                 break;
yading@10:             cg = vp6_coeff_groups[coeff_idx];
yading@10:             model1 = model2 = model->coeff_ract[pt][ct][cg];
yading@10:         }
yading@10: 
yading@10:         s->left_block[ff_vp56_b6to4[b]].not_null_dc =
yading@10:         s->above_blocks[s->above_block_idx[b]].not_null_dc = !!s->block_coeff[b][0];
yading@10:     }
yading@10: }
yading@10: 
yading@10: static int vp6_block_variance(uint8_t *src, int stride)
yading@10: {
yading@10:     int sum = 0, square_sum = 0;
yading@10:     int y, x;
yading@10: 
yading@10:     for (y=0; y<8; y+=2) {
yading@10:         for (x=0; x<8; x+=2) {
yading@10:             sum += src[x];
yading@10:             square_sum += src[x]*src[x];
yading@10:         }
yading@10:         src += 2*stride;
yading@10:     }
yading@10:     return (16*square_sum - sum*sum) >> 8;
yading@10: }
yading@10: 
yading@10: static void vp6_filter_hv4(uint8_t *dst, uint8_t *src, int stride,
yading@10:                            int delta, const int16_t *weights)
yading@10: {
yading@10:     int x, y;
yading@10: 
yading@10:     for (y=0; y<8; y++) {
yading@10:         for (x=0; x<8; x++) {
yading@10:             dst[x] = av_clip_uint8((  src[x-delta  ] * weights[0]
yading@10:                                  + src[x        ] * weights[1]
yading@10:                                  + src[x+delta  ] * weights[2]
yading@10:                                  + src[x+2*delta] * weights[3] + 64) >> 7);
yading@10:         }
yading@10:         src += stride;
yading@10:         dst += stride;
yading@10:     }
yading@10: }
yading@10: 
yading@10: static void vp6_filter_diag2(VP56Context *s, uint8_t *dst, uint8_t *src,
yading@10:                              int stride, int h_weight, int v_weight)
yading@10: {
yading@10:     uint8_t *tmp = s->edge_emu_buffer+16;
yading@10:     s->h264chroma.put_h264_chroma_pixels_tab[0](tmp, src, stride, 9, h_weight, 0);
yading@10:     s->h264chroma.put_h264_chroma_pixels_tab[0](dst, tmp, stride, 8, 0, v_weight);
yading@10: }
yading@10: 
yading@10: static void vp6_filter(VP56Context *s, uint8_t *dst, uint8_t *src,
yading@10:                        int offset1, int offset2, int stride,
yading@10:                        VP56mv mv, int mask, int select, int luma)
yading@10: {
yading@10:     int filter4 = 0;
yading@10:     int x8 = mv.x & mask;
yading@10:     int y8 = mv.y & mask;
yading@10: 
yading@10:     if (luma) {
yading@10:         x8 *= 2;
yading@10:         y8 *= 2;
yading@10:         filter4 = s->filter_mode;
yading@10:         if (filter4 == 2) {
yading@10:             if (s->max_vector_length &&
yading@10:                 (FFABS(mv.x) > s->max_vector_length ||
yading@10:                  FFABS(mv.y) > s->max_vector_length)) {
yading@10:                 filter4 = 0;
yading@10:             } else if (s->sample_variance_threshold
yading@10:                        && (vp6_block_variance(src+offset1, stride)
yading@10:                            < s->sample_variance_threshold)) {
yading@10:                 filter4 = 0;
yading@10:             }
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     if ((y8 && (offset2-offset1)*s->flip<0) || (!y8 && offset1 > offset2)) {
yading@10:         offset1 = offset2;
yading@10:     }
yading@10: 
yading@10:     if (filter4) {
yading@10:         if (!y8) {                      /* left or right combine */
yading@10:             vp6_filter_hv4(dst, src+offset1, stride, 1,
yading@10:                            vp6_block_copy_filter[select][x8]);
yading@10:         } else if (!x8) {               /* above or below combine */
yading@10:             vp6_filter_hv4(dst, src+offset1, stride, stride,
yading@10:                            vp6_block_copy_filter[select][y8]);
yading@10:         } else {
yading@10:             s->vp56dsp.vp6_filter_diag4(dst, src+offset1+((mv.x^mv.y)>>31), stride,
yading@10:                              vp6_block_copy_filter[select][x8],
yading@10:                              vp6_block_copy_filter[select][y8]);
yading@10:         }
yading@10:     } else {
yading@10:         if (!x8 || !y8) {
yading@10:             s->h264chroma.put_h264_chroma_pixels_tab[0](dst, src + offset1, stride, 8, x8, y8);
yading@10:         } else {
yading@10:             vp6_filter_diag2(s, dst, src+offset1 + ((mv.x^mv.y)>>31), stride, x8, y8);
yading@10:         }
yading@10:     }
yading@10: }
yading@10: 
yading@10: static av_cold void vp6_decode_init_context(VP56Context *s);
yading@10: 
yading@10: static av_cold int vp6_decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     VP56Context *s = avctx->priv_data;
yading@10:     int ret;
yading@10: 
yading@10:     if ((ret = ff_vp56_init(avctx, avctx->codec->id == AV_CODEC_ID_VP6,
yading@10:                             avctx->codec->id == AV_CODEC_ID_VP6A)) < 0)
yading@10:         return ret;
yading@10: 
yading@10:     vp6_decode_init_context(s);
yading@10: 
yading@10:     if (s->has_alpha) {
yading@10:         s->alpha_context = av_mallocz(sizeof(VP56Context));
yading@10:         ff_vp56_init_context(avctx, s->alpha_context,
yading@10:                              s->flip == -1, s->has_alpha);
yading@10:         vp6_decode_init_context(s->alpha_context);
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold void vp6_decode_init_context(VP56Context *s)
yading@10: {
yading@10:     s->deblock_filtering = 0;
yading@10:     s->vp56_coord_div = vp6_coord_div;
yading@10:     s->parse_vector_adjustment = vp6_parse_vector_adjustment;
yading@10:     s->filter = vp6_filter;
yading@10:     s->default_models_init = vp6_default_models_init;
yading@10:     s->parse_vector_models = vp6_parse_vector_models;
yading@10:     s->parse_coeff_models = vp6_parse_coeff_models;
yading@10:     s->parse_header = vp6_parse_header;
yading@10: }
yading@10: 
yading@10: static av_cold void vp6_decode_free_context(VP56Context *s);
yading@10: 
yading@10: static av_cold int vp6_decode_free(AVCodecContext *avctx)
yading@10: {
yading@10:     VP56Context *s = avctx->priv_data;
yading@10: 
yading@10:     ff_vp56_free(avctx);
yading@10:     vp6_decode_free_context(s);
yading@10: 
yading@10:     if (s->alpha_context) {
yading@10:         ff_vp56_free_context(s->alpha_context);
yading@10:         vp6_decode_free_context(s->alpha_context);
yading@10:         av_free(s->alpha_context);
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static av_cold void vp6_decode_free_context(VP56Context *s)
yading@10: {
yading@10:     int pt, ct, cg;
yading@10: 
yading@10:     for (pt=0; pt<2; pt++) {
yading@10:         ff_free_vlc(&s->dccv_vlc[pt]);
yading@10:         ff_free_vlc(&s->runv_vlc[pt]);
yading@10:         for (ct=0; ct<3; ct++)
yading@10:             for (cg=0; cg<6; cg++)
yading@10:                 ff_free_vlc(&s->ract_vlc[pt][ct][cg]);
yading@10:     }
yading@10: }
yading@10: 
yading@10: AVCodec ff_vp6_decoder = {
yading@10:     .name           = "vp6",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_VP6,
yading@10:     .priv_data_size = sizeof(VP56Context),
yading@10:     .init           = vp6_decode_init,
yading@10:     .close          = vp6_decode_free,
yading@10:     .decode         = ff_vp56_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("On2 VP6"),
yading@10: };
yading@10: 
yading@10: /* flash version, not flipped upside-down */
yading@10: AVCodec ff_vp6f_decoder = {
yading@10:     .name           = "vp6f",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_VP6F,
yading@10:     .priv_data_size = sizeof(VP56Context),
yading@10:     .init           = vp6_decode_init,
yading@10:     .close          = vp6_decode_free,
yading@10:     .decode         = ff_vp56_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version)"),
yading@10: };
yading@10: 
yading@10: /* flash version, not flipped upside-down, with alpha channel */
yading@10: AVCodec ff_vp6a_decoder = {
yading@10:     .name           = "vp6a",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_VP6A,
yading@10:     .priv_data_size = sizeof(VP56Context),
yading@10:     .init           = vp6_decode_init,
yading@10:     .close          = vp6_decode_free,
yading@10:     .decode         = ff_vp56_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1 | CODEC_CAP_SLICE_THREADS,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version, with alpha channel)"),
yading@10: };