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/**
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 * @file libavcodec/vp6.c
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 * VP6 compatible video decoder
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 *
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 * Copyright (C) 2006  Aurelien Jacobs <aurel@gnuage.org>
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 *
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 * The VP6F decoder accepts an optional 1 byte extradata. It is composed of:
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 *  - upper 4bits: difference between encoded width and visible width
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 *  - lower 4bits: difference between encoded height and visible height
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#include <stdlib.h>
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#include "avcodec.h"
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#include "dsputil.h"
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#include "get_bits.h"
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#include "huffman.h"
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#include "vp56.h"
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#include "vp56data.h"
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#include "vp6data.h"
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39

    
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static void vp6_parse_coeff(VP56Context *s);
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static void vp6_parse_coeff_huffman(VP56Context *s);
42

    
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static int vp6_parse_header(VP56Context *s, const uint8_t *buf, int buf_size,
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                            int *golden_frame)
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{
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    VP56RangeCoder *c = &s->c;
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    int parse_filter_info = 0;
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    int coeff_offset = 0;
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    int vrt_shift = 0;
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    int sub_version;
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    int rows, cols;
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    int res = 1;
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    int separated_coeff = buf[0] & 1;
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    s->framep[VP56_FRAME_CURRENT]->key_frame = !(buf[0] & 0x80);
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    vp56_init_dequant(s, (buf[0] >> 1) & 0x3F);
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    if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
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        sub_version = buf[1] >> 3;
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        if (sub_version > 8)
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            return 0;
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        s->filter_header = buf[1] & 0x06;
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        if (buf[1] & 1) {
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            av_log(s->avctx, AV_LOG_ERROR, "interlacing not supported\n");
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            return 0;
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        }
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        if (separated_coeff || !s->filter_header) {
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            coeff_offset = AV_RB16(buf+2) - 2;
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            buf += 2;
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            buf_size -= 2;
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        }
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        rows = buf[2];  /* number of stored macroblock rows */
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        cols = buf[3];  /* number of stored macroblock cols */
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        /* buf[4] is number of displayed macroblock rows */
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        /* buf[5] is number of displayed macroblock cols */
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        if (!s->macroblocks || /* first frame */
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            16*cols != s->avctx->coded_width ||
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            16*rows != s->avctx->coded_height) {
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            avcodec_set_dimensions(s->avctx, 16*cols, 16*rows);
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            if (s->avctx->extradata_size == 1) {
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                s->avctx->width  -= s->avctx->extradata[0] >> 4;
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                s->avctx->height -= s->avctx->extradata[0] & 0x0F;
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            }
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            res = 2;
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        }
88

    
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        vp56_init_range_decoder(c, buf+6, buf_size-6);
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        vp56_rac_gets(c, 2);
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        parse_filter_info = s->filter_header;
93
        if (sub_version < 8)
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            vrt_shift = 5;
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        s->sub_version = sub_version;
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    } else {
97
        if (!s->sub_version)
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            return 0;
99

    
100
        if (separated_coeff || !s->filter_header) {
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            coeff_offset = AV_RB16(buf+1) - 2;
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            buf += 2;
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            buf_size -= 2;
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        }
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        vp56_init_range_decoder(c, buf+1, buf_size-1);
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107
        *golden_frame = vp56_rac_get(c);
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        if (s->filter_header) {
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            s->deblock_filtering = vp56_rac_get(c);
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            if (s->deblock_filtering)
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                vp56_rac_get(c);
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            if (s->sub_version > 7)
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                parse_filter_info = vp56_rac_get(c);
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        }
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    }
116

    
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    if (parse_filter_info) {
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        if (vp56_rac_get(c)) {
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            s->filter_mode = 2;
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            s->sample_variance_threshold = vp56_rac_gets(c, 5) << vrt_shift;
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            s->max_vector_length = 2 << vp56_rac_gets(c, 3);
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        } else if (vp56_rac_get(c)) {
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            s->filter_mode = 1;
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        } else {
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            s->filter_mode = 0;
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        }
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        if (s->sub_version > 7)
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            s->filter_selection = vp56_rac_gets(c, 4);
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        else
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            s->filter_selection = 16;
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    }
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133
    s->use_huffman = vp56_rac_get(c);
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135
    s->parse_coeff = vp6_parse_coeff;
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    if (coeff_offset) {
137
        buf      += coeff_offset;
138
        buf_size -= coeff_offset;
139
        if (buf_size < 0)
140
            return 0;
141
        if (s->use_huffman) {
142
            s->parse_coeff = vp6_parse_coeff_huffman;
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            init_get_bits(&s->gb, buf, buf_size<<3);
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        } else {
145
            vp56_init_range_decoder(&s->cc, buf, buf_size);
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            s->ccp = &s->cc;
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        }
148
    } else {
149
        s->ccp = &s->c;
150
    }
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152
    return res;
153
}
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static void vp6_coeff_order_table_init(VP56Context *s)
156
{
157
    int i, pos, idx = 1;
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159
    s->modelp->coeff_index_to_pos[0] = 0;
160
    for (i=0; i<16; i++)
161
        for (pos=1; pos<64; pos++)
162
            if (s->modelp->coeff_reorder[pos] == i)
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                s->modelp->coeff_index_to_pos[idx++] = pos;
164
}
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166
static void vp6_default_models_init(VP56Context *s)
167
{
168
    VP56Model *model = s->modelp;
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170
    model->vector_dct[0] = 0xA2;
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    model->vector_dct[1] = 0xA4;
172
    model->vector_sig[0] = 0x80;
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    model->vector_sig[1] = 0x80;
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    memcpy(model->mb_types_stats, vp56_def_mb_types_stats, sizeof(model->mb_types_stats));
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    memcpy(model->vector_fdv, vp6_def_fdv_vector_model, sizeof(model->vector_fdv));
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    memcpy(model->vector_pdv, vp6_def_pdv_vector_model, sizeof(model->vector_pdv));
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    memcpy(model->coeff_runv, vp6_def_runv_coeff_model, sizeof(model->coeff_runv));
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    memcpy(model->coeff_reorder, vp6_def_coeff_reorder, sizeof(model->coeff_reorder));
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    vp6_coeff_order_table_init(s);
182
}
183

    
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static void vp6_parse_vector_models(VP56Context *s)
185
{
186
    VP56RangeCoder *c = &s->c;
187
    VP56Model *model = s->modelp;
188
    int comp, node;
189

    
190
    for (comp=0; comp<2; comp++) {
191
        if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][0]))
192
            model->vector_dct[comp] = vp56_rac_gets_nn(c, 7);
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        if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][1]))
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            model->vector_sig[comp] = vp56_rac_gets_nn(c, 7);
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    }
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197
    for (comp=0; comp<2; comp++)
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        for (node=0; node<7; node++)
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            if (vp56_rac_get_prob(c, vp6_pdv_pct[comp][node]))
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                model->vector_pdv[comp][node] = vp56_rac_gets_nn(c, 7);
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202
    for (comp=0; comp<2; comp++)
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        for (node=0; node<8; node++)
204
            if (vp56_rac_get_prob(c, vp6_fdv_pct[comp][node]))
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                model->vector_fdv[comp][node] = vp56_rac_gets_nn(c, 7);
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}
207

    
208
/* nodes must ascend by count, but with descending symbol order */
209
static int vp6_huff_cmp(const void *va, const void *vb)
210
{
211
    const Node *a = va, *b = vb;
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    return (a->count - b->count)*16 + (b->sym - a->sym);
213
}
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static void vp6_build_huff_tree(VP56Context *s, uint8_t coeff_model[],
216
                                const uint8_t *map, unsigned size, VLC *vlc)
217
{
218
    Node nodes[2*size], *tmp = &nodes[size];
219
    int a, b, i;
220

    
221
    /* first compute probabilities from model */
222
    tmp[0].count = 256;
223
    for (i=0; i<size-1; i++) {
224
        a = tmp[i].count *        coeff_model[i]  >> 8;
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        b = tmp[i].count * (255 - coeff_model[i]) >> 8;
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        nodes[map[2*i  ]].count = a + !a;
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        nodes[map[2*i+1]].count = b + !b;
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    }
229

    
230
    /* then build the huffman tree accodring to probabilities */
231
    ff_huff_build_tree(s->avctx, vlc, size, nodes, vp6_huff_cmp,
232
                       FF_HUFFMAN_FLAG_HNODE_FIRST);
233
}
234

    
235
static void vp6_parse_coeff_models(VP56Context *s)
236
{
237
    VP56RangeCoder *c = &s->c;
238
    VP56Model *model = s->modelp;
239
    int def_prob[11];
240
    int node, cg, ctx, pos;
241
    int ct;    /* code type */
242
    int pt;    /* plane type (0 for Y, 1 for U or V) */
243

    
244
    memset(def_prob, 0x80, sizeof(def_prob));
245

    
246
    for (pt=0; pt<2; pt++)
247
        for (node=0; node<11; node++)
248
            if (vp56_rac_get_prob(c, vp6_dccv_pct[pt][node])) {
249
                def_prob[node] = vp56_rac_gets_nn(c, 7);
250
                model->coeff_dccv[pt][node] = def_prob[node];
251
            } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
252
                model->coeff_dccv[pt][node] = def_prob[node];
253
            }
254

    
255
    if (vp56_rac_get(c)) {
256
        for (pos=1; pos<64; pos++)
257
            if (vp56_rac_get_prob(c, vp6_coeff_reorder_pct[pos]))
258
                model->coeff_reorder[pos] = vp56_rac_gets(c, 4);
259
        vp6_coeff_order_table_init(s);
260
    }
261

    
262
    for (cg=0; cg<2; cg++)
263
        for (node=0; node<14; node++)
264
            if (vp56_rac_get_prob(c, vp6_runv_pct[cg][node]))
265
                model->coeff_runv[cg][node] = vp56_rac_gets_nn(c, 7);
266

    
267
    for (ct=0; ct<3; ct++)
268
        for (pt=0; pt<2; pt++)
269
            for (cg=0; cg<6; cg++)
270
                for (node=0; node<11; node++)
271
                    if (vp56_rac_get_prob(c, vp6_ract_pct[ct][pt][cg][node])) {
272
                        def_prob[node] = vp56_rac_gets_nn(c, 7);
273
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
274
                    } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
275
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
276
                    }
277

    
278
    if (s->use_huffman) {
279
        for (pt=0; pt<2; pt++) {
280
            vp6_build_huff_tree(s, model->coeff_dccv[pt],
281
                                vp6_huff_coeff_map, 12, &s->dccv_vlc[pt]);
282
            vp6_build_huff_tree(s, model->coeff_runv[pt],
283
                                vp6_huff_run_map, 9, &s->runv_vlc[pt]);
284
            for (ct=0; ct<3; ct++)
285
                for (cg = 0; cg < 6; cg++)
286
                    vp6_build_huff_tree(s, model->coeff_ract[pt][ct][cg],
287
                                        vp6_huff_coeff_map, 12,
288
                                        &s->ract_vlc[pt][ct][cg]);
289
        }
290
        memset(s->nb_null, 0, sizeof(s->nb_null));
291
    } else {
292
    /* coeff_dcct is a linear combination of coeff_dccv */
293
    for (pt=0; pt<2; pt++)
294
        for (ctx=0; ctx<3; ctx++)
295
            for (node=0; node<5; node++)
296
                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);
297
    }
298
}
299

    
300
static void vp6_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
301
{
302
    VP56RangeCoder *c = &s->c;
303
    VP56Model *model = s->modelp;
304
    int comp;
305

    
306
    *vect = (VP56mv) {0,0};
307
    if (s->vector_candidate_pos < 2)
308
        *vect = s->vector_candidate[0];
309

    
310
    for (comp=0; comp<2; comp++) {
311
        int i, delta = 0;
312

    
313
        if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
314
            static const uint8_t prob_order[] = {0, 1, 2, 7, 6, 5, 4};
315
            for (i=0; i<sizeof(prob_order); i++) {
316
                int j = prob_order[i];
317
                delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][j])<<j;
318
            }
319
            if (delta & 0xF0)
320
                delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][3])<<3;
321
            else
322
                delta |= 8;
323
        } else {
324
            delta = vp56_rac_get_tree(c, vp56_pva_tree,
325
                                      model->vector_pdv[comp]);
326
        }
327

    
328
        if (delta && vp56_rac_get_prob(c, model->vector_sig[comp]))
329
            delta = -delta;
330

    
331
        if (!comp)
332
            vect->x += delta;
333
        else
334
            vect->y += delta;
335
    }
336
}
337

    
338
/**
339
 * Read number of consecutive blocks with null DC or AC.
340
 * This value is < 74.
341
 */
342
static unsigned vp6_get_nb_null(VP56Context *s)
343
{
344
    unsigned val = get_bits(&s->gb, 2);
345
    if (val == 2)
346
        val += get_bits(&s->gb, 2);
347
    else if (val == 3) {
348
        val = get_bits1(&s->gb) << 2;
349
        val = 6+val + get_bits(&s->gb, 2+val);
350
    }
351
    return val;
352
}
353

    
354
static void vp6_parse_coeff_huffman(VP56Context *s)
355
{
356
    VP56Model *model = s->modelp;
357
    uint8_t *permute = s->scantable.permutated;
358
    VLC *vlc_coeff;
359
    int coeff, sign, coeff_idx;
360
    int b, cg, idx;
361
    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
362

    
363
    for (b=0; b<6; b++) {
364
        int ct = 0;    /* code type */
365
        if (b > 3) pt = 1;
366
        vlc_coeff = &s->dccv_vlc[pt];
367

    
368
        for (coeff_idx=0; coeff_idx<64; ) {
369
            int run = 1;
370
            if (coeff_idx<2 && s->nb_null[coeff_idx][pt]) {
371
                s->nb_null[coeff_idx][pt]--;
372
                if (coeff_idx)
373
                    break;
374
            } else {
375
                coeff = get_vlc2(&s->gb, vlc_coeff->table, 9, 3);
376
                if (coeff == 0) {
377
                    if (coeff_idx) {
378
                        int pt = (coeff_idx >= 6);
379
                        run += get_vlc2(&s->gb, s->runv_vlc[pt].table, 9, 3);
380
                        if (run >= 9)
381
                            run += get_bits(&s->gb, 6);
382
                    } else
383
                        s->nb_null[0][pt] = vp6_get_nb_null(s);
384
                    ct = 0;
385
                } else if (coeff == 11) {  /* end of block */
386
                    if (coeff_idx == 1)    /* first AC coeff ? */
387
                        s->nb_null[1][pt] = vp6_get_nb_null(s);
388
                    break;
389
                } else {
390
                    int coeff2 = vp56_coeff_bias[coeff];
391
                    if (coeff > 4)
392
                        coeff2 += get_bits(&s->gb, coeff <= 9 ? coeff - 4 : 11);
393
                    ct = 1 + (coeff2 > 1);
394
                    sign = get_bits1(&s->gb);
395
                    coeff2 = (coeff2 ^ -sign) + sign;
396
                    if (coeff_idx)
397
                        coeff2 *= s->dequant_ac;
398
                    idx = model->coeff_index_to_pos[coeff_idx];
399
                    s->block_coeff[b][permute[idx]] = coeff2;
400
                }
401
            }
402
            coeff_idx+=run;
403
            cg = FFMIN(vp6_coeff_groups[coeff_idx], 3);
404
            vlc_coeff = &s->ract_vlc[pt][ct][cg];
405
        }
406
    }
407
}
408

    
409
static void vp6_parse_coeff(VP56Context *s)
410
{
411
    VP56RangeCoder *c = s->ccp;
412
    VP56Model *model = s->modelp;
413
    uint8_t *permute = s->scantable.permutated;
414
    uint8_t *model1, *model2, *model3;
415
    int coeff, sign, coeff_idx;
416
    int b, i, cg, idx, ctx;
417
    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
418

    
419
    for (b=0; b<6; b++) {
420
        int ct = 1;    /* code type */
421
        int run = 1;
422

    
423
        if (b > 3) pt = 1;
424

    
425
        ctx = s->left_block[vp56_b6to4[b]].not_null_dc
426
              + s->above_blocks[s->above_block_idx[b]].not_null_dc;
427
        model1 = model->coeff_dccv[pt];
428
        model2 = model->coeff_dcct[pt][ctx];
429

    
430
        for (coeff_idx=0; coeff_idx<64; ) {
431
            if ((coeff_idx>1 && ct==0) || vp56_rac_get_prob(c, model2[0])) {
432
                /* parse a coeff */
433
                if (vp56_rac_get_prob(c, model2[2])) {
434
                    if (vp56_rac_get_prob(c, model2[3])) {
435
                        idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
436
                        coeff = vp56_coeff_bias[idx+5];
437
                        for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
438
                            coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
439
                    } else {
440
                        if (vp56_rac_get_prob(c, model2[4]))
441
                            coeff = 3 + vp56_rac_get_prob(c, model1[5]);
442
                        else
443
                            coeff = 2;
444
                    }
445
                    ct = 2;
446
                } else {
447
                    ct = 1;
448
                    coeff = 1;
449
                }
450
                sign = vp56_rac_get(c);
451
                coeff = (coeff ^ -sign) + sign;
452
                if (coeff_idx)
453
                    coeff *= s->dequant_ac;
454
                idx = model->coeff_index_to_pos[coeff_idx];
455
                s->block_coeff[b][permute[idx]] = coeff;
456
                run = 1;
457
            } else {
458
                /* parse a run */
459
                ct = 0;
460
                if (coeff_idx > 0) {
461
                    if (!vp56_rac_get_prob(c, model2[1]))
462
                        break;
463

    
464
                    model3 = model->coeff_runv[coeff_idx >= 6];
465
                    run = vp56_rac_get_tree(c, vp6_pcr_tree, model3);
466
                    if (!run)
467
                        for (run=9, i=0; i<6; i++)
468
                            run += vp56_rac_get_prob(c, model3[i+8]) << i;
469
                }
470
            }
471

    
472
            cg = vp6_coeff_groups[coeff_idx+=run];
473
            model1 = model2 = model->coeff_ract[pt][ct][cg];
474
        }
475

    
476
        s->left_block[vp56_b6to4[b]].not_null_dc =
477
        s->above_blocks[s->above_block_idx[b]].not_null_dc = !!s->block_coeff[b][0];
478
    }
479
}
480

    
481
static int vp6_adjust(int v, int t)
482
{
483
    int V = v, s = v >> 31;
484
    V ^= s;
485
    V -= s;
486
    if (V-t-1 >= (unsigned)(t-1))
487
        return v;
488
    V = 2*t - V;
489
    V += s;
490
    V ^= s;
491
    return V;
492
}
493

    
494
static int vp6_block_variance(uint8_t *src, int stride)
495
{
496
    int sum = 0, square_sum = 0;
497
    int y, x;
498

    
499
    for (y=0; y<8; y+=2) {
500
        for (x=0; x<8; x+=2) {
501
            sum += src[x];
502
            square_sum += src[x]*src[x];
503
        }
504
        src += 2*stride;
505
    }
506
    return (16*square_sum - sum*sum) >> 8;
507
}
508

    
509
static void vp6_filter_hv4(uint8_t *dst, uint8_t *src, int stride,
510
                           int delta, const int16_t *weights)
511
{
512
    int x, y;
513

    
514
    for (y=0; y<8; y++) {
515
        for (x=0; x<8; x++) {
516
            dst[x] = av_clip_uint8((  src[x-delta  ] * weights[0]
517
                                 + src[x        ] * weights[1]
518
                                 + src[x+delta  ] * weights[2]
519
                                 + src[x+2*delta] * weights[3] + 64) >> 7);
520
        }
521
        src += stride;
522
        dst += stride;
523
    }
524
}
525

    
526
static void vp6_filter_diag2(VP56Context *s, uint8_t *dst, uint8_t *src,
527
                             int stride, int h_weight, int v_weight)
528
{
529
    uint8_t *tmp = s->edge_emu_buffer+16;
530
    s->dsp.put_h264_chroma_pixels_tab[0](tmp, src, stride, 9, h_weight, 0);
531
    s->dsp.put_h264_chroma_pixels_tab[0](dst, tmp, stride, 8, 0, v_weight);
532
}
533

    
534
static void vp6_filter(VP56Context *s, uint8_t *dst, uint8_t *src,
535
                       int offset1, int offset2, int stride,
536
                       VP56mv mv, int mask, int select, int luma)
537
{
538
    int filter4 = 0;
539
    int x8 = mv.x & mask;
540
    int y8 = mv.y & mask;
541

    
542
    if (luma) {
543
        x8 *= 2;
544
        y8 *= 2;
545
        filter4 = s->filter_mode;
546
        if (filter4 == 2) {
547
            if (s->max_vector_length &&
548
                (FFABS(mv.x) > s->max_vector_length ||
549
                 FFABS(mv.y) > s->max_vector_length)) {
550
                filter4 = 0;
551
            } else if (s->sample_variance_threshold
552
                       && (vp6_block_variance(src+offset1, stride)
553
                           < s->sample_variance_threshold)) {
554
                filter4 = 0;
555
            }
556
        }
557
    }
558

    
559
    if ((y8 && (offset2-offset1)*s->flip<0) || (!y8 && offset1 > offset2)) {
560
        offset1 = offset2;
561
    }
562

    
563
    if (filter4) {
564
        if (!y8) {                      /* left or right combine */
565
            vp6_filter_hv4(dst, src+offset1, stride, 1,
566
                           vp6_block_copy_filter[select][x8]);
567
        } else if (!x8) {               /* above or below combine */
568
            vp6_filter_hv4(dst, src+offset1, stride, stride,
569
                           vp6_block_copy_filter[select][y8]);
570
        } else {
571
            s->dsp.vp6_filter_diag4(dst, src+offset1+((mv.x^mv.y)>>31), stride,
572
                             vp6_block_copy_filter[select][x8],
573
                             vp6_block_copy_filter[select][y8]);
574
        }
575
    } else {
576
        if (!x8 || !y8) {
577
            s->dsp.put_h264_chroma_pixels_tab[0](dst, src+offset1, stride, 8, x8, y8);
578
        } else {
579
            vp6_filter_diag2(s, dst, src+offset1 + ((mv.x^mv.y)>>31), stride, x8, y8);
580
        }
581
    }
582
}
583

    
584
static av_cold int vp6_decode_init(AVCodecContext *avctx)
585
{
586
    VP56Context *s = avctx->priv_data;
587

    
588
    vp56_init(avctx, avctx->codec->id == CODEC_ID_VP6,
589
                     avctx->codec->id == CODEC_ID_VP6A);
590
    s->vp56_coord_div = vp6_coord_div;
591
    s->parse_vector_adjustment = vp6_parse_vector_adjustment;
592
    s->adjust = vp6_adjust;
593
    s->filter = vp6_filter;
594
    s->default_models_init = vp6_default_models_init;
595
    s->parse_vector_models = vp6_parse_vector_models;
596
    s->parse_coeff_models = vp6_parse_coeff_models;
597
    s->parse_header = vp6_parse_header;
598

    
599
    return 0;
600
}
601

    
602
AVCodec vp6_decoder = {
603
    "vp6",
604
    CODEC_TYPE_VIDEO,
605
    CODEC_ID_VP6,
606
    sizeof(VP56Context),
607
    vp6_decode_init,
608
    NULL,
609
    vp56_free,
610
    vp56_decode_frame,
611
    CODEC_CAP_DR1,
612
    .long_name = NULL_IF_CONFIG_SMALL("On2 VP6"),
613
};
614

    
615
/* flash version, not flipped upside-down */
616
AVCodec vp6f_decoder = {
617
    "vp6f",
618
    CODEC_TYPE_VIDEO,
619
    CODEC_ID_VP6F,
620
    sizeof(VP56Context),
621
    vp6_decode_init,
622
    NULL,
623
    vp56_free,
624
    vp56_decode_frame,
625
    CODEC_CAP_DR1,
626
    .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version)"),
627
};
628

    
629
/* flash version, not flipped upside-down, with alpha channel */
630
AVCodec vp6a_decoder = {
631
    "vp6a",
632
    CODEC_TYPE_VIDEO,
633
    CODEC_ID_VP6A,
634
    sizeof(VP56Context),
635
    vp6_decode_init,
636
    NULL,
637
    vp56_free,
638
    vp56_decode_frame,
639
    CODEC_CAP_DR1,
640
    .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version, with alpha channel)"),
641
};