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/**
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 * @file 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 "bitstream.h"
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#include "huffman.h"
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#include "mpegvideo.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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static void vp6_parse_coeff(vp56_context_t *s);
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static void vp6_parse_coeff_huffman(vp56_context_t *s);
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static int vp6_parse_header(vp56_context_t *s, uint8_t *buf, int buf_size,
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                            int *golden_frame)
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{
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    vp56_range_coder_t *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 (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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        }
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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;
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        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 {
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        if (!s->sub_version)
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            return 0;
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        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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        *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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    }
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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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    s->use_huffman = vp56_rac_get(c);
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    s->parse_coeff = vp6_parse_coeff;
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    if (coeff_offset) {
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        buf      += coeff_offset;
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        buf_size -= coeff_offset;
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        if (s->use_huffman) {
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            s->parse_coeff = vp6_parse_coeff_huffman;
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            init_get_bits(&s->gb, buf, buf_size);
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        } else {
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            vp56_init_range_decoder(&s->cc, buf, buf_size);
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            s->ccp = &s->cc;
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        }
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    } else {
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        s->ccp = &s->c;
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    }
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    return res;
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}
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static void vp6_coeff_order_table_init(vp56_context_t *s)
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{
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    int i, pos, idx = 1;
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    s->modelp->coeff_index_to_pos[0] = 0;
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    for (i=0; i<16; i++)
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        for (pos=1; pos<64; pos++)
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            if (s->modelp->coeff_reorder[pos] == i)
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                s->modelp->coeff_index_to_pos[idx++] = pos;
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}
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static void vp6_default_models_init(vp56_context_t *s)
165
{
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    vp56_model_t *model = s->modelp;
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    model->vector_dct[0] = 0xA2;
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    model->vector_dct[1] = 0xA4;
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    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);
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}
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static void vp6_parse_vector_models(vp56_context_t *s)
183
{
184
    vp56_range_coder_t *c = &s->c;
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    vp56_model_t *model = s->modelp;
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    int comp, node;
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188
    for (comp=0; comp<2; comp++) {
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        if (vp56_rac_get_prob(c, vp6_sig_dct_pct[comp][0]))
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            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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    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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    for (comp=0; comp<2; comp++)
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        for (node=0; node<8; node++)
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            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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}
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static int vp6_huff_cmp(const void *va, const void *vb)
207
{
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    const Node *a = va, *b = vb;
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    return a->count >= b->count;
210
}
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static void vp6_build_huff_tree(vp56_context_t *s, uint8_t coeff_model[],
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                                const uint8_t *map, unsigned size, VLC *vlc)
214
{
215
    Node nodes[2*size], *tmp = &nodes[size];
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    int a, b, i;
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218
    /* first compute probabilities from model */
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    tmp[0].count = 256;
220
    for (i=0; i<size-1; i++) {
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        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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    }
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    /* then build the huffman tree accodring to probabilities */
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    ff_huff_build_tree(s->avctx, vlc, size, nodes, vp6_huff_cmp, 1);
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}
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231
static void vp6_parse_coeff_models(vp56_context_t *s)
232
{
233
    vp56_range_coder_t *c = &s->c;
234
    vp56_model_t *model = s->modelp;
235
    int def_prob[11];
236
    int node, cg, ctx, pos;
237
    int ct;    /* code type */
238
    int pt;    /* plane type (0 for Y, 1 for U or V) */
239

    
240
    memset(def_prob, 0x80, sizeof(def_prob));
241

    
242
    for (pt=0; pt<2; pt++)
243
        for (node=0; node<11; node++)
244
            if (vp56_rac_get_prob(c, vp6_dccv_pct[pt][node])) {
245
                def_prob[node] = vp56_rac_gets_nn(c, 7);
246
                model->coeff_dccv[pt][node] = def_prob[node];
247
            } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
248
                model->coeff_dccv[pt][node] = def_prob[node];
249
            }
250

    
251
    if (vp56_rac_get(c)) {
252
        for (pos=1; pos<64; pos++)
253
            if (vp56_rac_get_prob(c, vp6_coeff_reorder_pct[pos]))
254
                model->coeff_reorder[pos] = vp56_rac_gets(c, 4);
255
        vp6_coeff_order_table_init(s);
256
    }
257

    
258
    for (cg=0; cg<2; cg++)
259
        for (node=0; node<14; node++)
260
            if (vp56_rac_get_prob(c, vp6_runv_pct[cg][node]))
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                model->coeff_runv[cg][node] = vp56_rac_gets_nn(c, 7);
262

    
263
    for (ct=0; ct<3; ct++)
264
        for (pt=0; pt<2; pt++)
265
            for (cg=0; cg<6; cg++)
266
                for (node=0; node<11; node++)
267
                    if (vp56_rac_get_prob(c, vp6_ract_pct[ct][pt][cg][node])) {
268
                        def_prob[node] = vp56_rac_gets_nn(c, 7);
269
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
270
                    } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
271
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
272
                    }
273

    
274
    if (s->use_huffman) {
275
        for (pt=0; pt<2; pt++) {
276
            vp6_build_huff_tree(s, model->coeff_dccv[pt],
277
                                vp6_huff_coeff_map, 12, &s->dccv_vlc[pt]);
278
            vp6_build_huff_tree(s, model->coeff_runv[pt],
279
                                vp6_huff_run_map, 9, &s->runv_vlc[pt]);
280
            for (ct=0; ct<3; ct++)
281
                for (cg = 0; cg < 6; cg++)
282
                    vp6_build_huff_tree(s, model->coeff_ract[pt][ct][cg],
283
                                        vp6_huff_coeff_map, 12,
284
                                        &s->ract_vlc[pt][ct][cg]);
285
        }
286
        memset(s->nb_null, 0, sizeof(s->nb_null));
287
    } else {
288
    /* coeff_dcct is a linear combination of coeff_dccv */
289
    for (pt=0; pt<2; pt++)
290
        for (ctx=0; ctx<3; ctx++)
291
            for (node=0; node<5; node++)
292
                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);
293
    }
294
}
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296
static void vp6_parse_vector_adjustment(vp56_context_t *s, vp56_mv_t *vect)
297
{
298
    vp56_range_coder_t *c = &s->c;
299
    vp56_model_t *model = s->modelp;
300
    int comp;
301

    
302
    *vect = (vp56_mv_t) {0,0};
303
    if (s->vector_candidate_pos < 2)
304
        *vect = s->vector_candidate[0];
305

    
306
    for (comp=0; comp<2; comp++) {
307
        int i, delta = 0;
308

    
309
        if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
310
            static const uint8_t prob_order[] = {0, 1, 2, 7, 6, 5, 4};
311
            for (i=0; i<sizeof(prob_order); i++) {
312
                int j = prob_order[i];
313
                delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][j])<<j;
314
            }
315
            if (delta & 0xF0)
316
                delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][3])<<3;
317
            else
318
                delta |= 8;
319
        } else {
320
            delta = vp56_rac_get_tree(c, vp56_pva_tree,
321
                                      model->vector_pdv[comp]);
322
        }
323

    
324
        if (delta && vp56_rac_get_prob(c, model->vector_sig[comp]))
325
            delta = -delta;
326

    
327
        if (!comp)
328
            vect->x += delta;
329
        else
330
            vect->y += delta;
331
    }
332
}
333

    
334
/**
335
 * Read number of consecutive blocks with null DC or AC.
336
 * This value is < 74.
337
 */
338
static unsigned vp6_get_nb_null(vp56_context_t *s)
339
{
340
    unsigned val = get_bits(&s->gb, 2);
341
    if (val == 2)
342
        val += get_bits(&s->gb, 2);
343
    else if (val == 3) {
344
        val = get_bits1(&s->gb) << 2;
345
        val = 6+val + get_bits(&s->gb, 2+val);
346
    }
347
    return val;
348
}
349

    
350
static void vp6_parse_coeff_huffman(vp56_context_t *s)
351
{
352
    vp56_model_t *model = s->modelp;
353
    uint8_t *permute = s->scantable.permutated;
354
    VLC *vlc_coeff;
355
    int coeff, sign, coeff_idx;
356
    int b, cg, idx;
357
    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
358

    
359
    for (b=0; b<6; b++) {
360
        int ct = 0;    /* code type */
361
        if (b > 3) pt = 1;
362
        vlc_coeff = &s->dccv_vlc[pt];
363

    
364
        for (coeff_idx=0; coeff_idx<64; ) {
365
            int run = 1;
366
            if (coeff_idx<2 && s->nb_null[coeff_idx][pt]) {
367
                s->nb_null[coeff_idx][pt]--;
368
                if (coeff_idx)
369
                    break;
370
            } else {
371
                coeff = get_vlc2(&s->gb, vlc_coeff->table, 9, 3);
372
                if (coeff == 0) {
373
                    if (coeff_idx) {
374
                        int pt = (coeff_idx >= 6);
375
                        run += get_vlc2(&s->gb, s->runv_vlc[pt].table, 9, 3);
376
                        if (run >= 9)
377
                            run += get_bits(&s->gb, 6);
378
                    } else
379
                        s->nb_null[0][pt] = vp6_get_nb_null(s);
380
                    ct = 0;
381
                } else if (coeff == 11) {  /* end of block */
382
                    if (coeff_idx == 1)    /* first AC coeff ? */
383
                        s->nb_null[1][pt] = vp6_get_nb_null(s);
384
                    break;
385
                } else {
386
                    int coeff2 = vp56_coeff_bias[coeff];
387
                    if (coeff > 4)
388
                        coeff2 += get_bits(&s->gb, coeff <= 9 ? coeff - 4 : 11);
389
                    ct = 1 + (coeff2 > 1);
390
                    sign = get_bits1(&s->gb);
391
                    coeff2 = (coeff2 ^ -sign) + sign;
392
                    if (coeff_idx)
393
                        coeff2 *= s->dequant_ac;
394
                    idx = model->coeff_index_to_pos[coeff_idx];
395
                    s->block_coeff[b][permute[idx]] = coeff2;
396
                }
397
            }
398
            coeff_idx+=run;
399
            cg = FFMIN(vp6_coeff_groups[coeff_idx], 3);
400
            vlc_coeff = &s->ract_vlc[pt][ct][cg];
401
        }
402
    }
403
}
404

    
405
static void vp6_parse_coeff(vp56_context_t *s)
406
{
407
    vp56_range_coder_t *c = s->ccp;
408
    vp56_model_t *model = s->modelp;
409
    uint8_t *permute = s->scantable.permutated;
410
    uint8_t *model1, *model2, *model3;
411
    int coeff, sign, coeff_idx;
412
    int b, i, cg, idx, ctx;
413
    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
414

    
415
    for (b=0; b<6; b++) {
416
        int ct = 1;    /* code type */
417
        int run = 1;
418

    
419
        if (b > 3) pt = 1;
420

    
421
        ctx = s->left_block[vp56_b6to4[b]].not_null_dc
422
              + s->above_blocks[s->above_block_idx[b]].not_null_dc;
423
        model1 = model->coeff_dccv[pt];
424
        model2 = model->coeff_dcct[pt][ctx];
425

    
426
        for (coeff_idx=0; coeff_idx<64; ) {
427
            if ((coeff_idx>1 && ct==0) || vp56_rac_get_prob(c, model2[0])) {
428
                /* parse a coeff */
429
                if (vp56_rac_get_prob(c, model2[2])) {
430
                    if (vp56_rac_get_prob(c, model2[3])) {
431
                        idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
432
                        coeff = vp56_coeff_bias[idx+5];
433
                        for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
434
                            coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
435
                    } else {
436
                        if (vp56_rac_get_prob(c, model2[4]))
437
                            coeff = 3 + vp56_rac_get_prob(c, model1[5]);
438
                        else
439
                            coeff = 2;
440
                    }
441
                    ct = 2;
442
                } else {
443
                    ct = 1;
444
                    coeff = 1;
445
                }
446
                sign = vp56_rac_get(c);
447
                coeff = (coeff ^ -sign) + sign;
448
                if (coeff_idx)
449
                    coeff *= s->dequant_ac;
450
                idx = model->coeff_index_to_pos[coeff_idx];
451
                s->block_coeff[b][permute[idx]] = coeff;
452
                run = 1;
453
            } else {
454
                /* parse a run */
455
                ct = 0;
456
                if (coeff_idx > 0) {
457
                    if (!vp56_rac_get_prob(c, model2[1]))
458
                        break;
459

    
460
                    model3 = model->coeff_runv[coeff_idx >= 6];
461
                    run = vp56_rac_get_tree(c, vp6_pcr_tree, model3);
462
                    if (!run)
463
                        for (run=9, i=0; i<6; i++)
464
                            run += vp56_rac_get_prob(c, model3[i+8]) << i;
465
                }
466
            }
467

    
468
            cg = vp6_coeff_groups[coeff_idx+=run];
469
            model1 = model2 = model->coeff_ract[pt][ct][cg];
470
        }
471

    
472
        s->left_block[vp56_b6to4[b]].not_null_dc =
473
        s->above_blocks[s->above_block_idx[b]].not_null_dc = !!s->block_coeff[b][0];
474
    }
475
}
476

    
477
static int vp6_adjust(int v, int t)
478
{
479
    int V = v, s = v >> 31;
480
    V ^= s;
481
    V -= s;
482
    if (V-t-1 >= (unsigned)(t-1))
483
        return v;
484
    V = 2*t - V;
485
    V += s;
486
    V ^= s;
487
    return V;
488
}
489

    
490
static int vp6_block_variance(uint8_t *src, int stride)
491
{
492
    int sum = 0, square_sum = 0;
493
    int y, x;
494

    
495
    for (y=0; y<8; y+=2) {
496
        for (x=0; x<8; x+=2) {
497
            sum += src[x];
498
            square_sum += src[x]*src[x];
499
        }
500
        src += 2*stride;
501
    }
502
    return (16*square_sum - sum*sum) >> 8;
503
}
504

    
505
static void vp6_filter_hv4(uint8_t *dst, uint8_t *src, int stride,
506
                           int delta, const int16_t *weights)
507
{
508
    int x, y;
509

    
510
    for (y=0; y<8; y++) {
511
        for (x=0; x<8; x++) {
512
            dst[x] = av_clip_uint8((  src[x-delta  ] * weights[0]
513
                                 + src[x        ] * weights[1]
514
                                 + src[x+delta  ] * weights[2]
515
                                 + src[x+2*delta] * weights[3] + 64) >> 7);
516
        }
517
        src += stride;
518
        dst += stride;
519
    }
520
}
521

    
522
static void vp6_filter_diag2(vp56_context_t *s, uint8_t *dst, uint8_t *src,
523
                             int stride, int h_weight, int v_weight)
524
{
525
    uint8_t *tmp = s->edge_emu_buffer+16;
526
    s->dsp.put_h264_chroma_pixels_tab[0](tmp, src, stride, 9, h_weight, 0);
527
    s->dsp.put_h264_chroma_pixels_tab[0](dst, tmp, stride, 8, 0, v_weight);
528
}
529

    
530
static void vp6_filter_diag4(uint8_t *dst, uint8_t *src, int stride,
531
                             const int16_t *h_weights,const int16_t *v_weights)
532
{
533
    int x, y;
534
    int tmp[8*11];
535
    int *t = tmp;
536

    
537
    src -= stride;
538

    
539
    for (y=0; y<11; y++) {
540
        for (x=0; x<8; x++) {
541
            t[x] = av_clip_uint8((  src[x-1] * h_weights[0]
542
                               + src[x  ] * h_weights[1]
543
                               + src[x+1] * h_weights[2]
544
                               + src[x+2] * h_weights[3] + 64) >> 7);
545
        }
546
        src += stride;
547
        t += 8;
548
    }
549

    
550
    t = tmp + 8;
551
    for (y=0; y<8; y++) {
552
        for (x=0; x<8; x++) {
553
            dst[x] = av_clip_uint8((  t[x-8 ] * v_weights[0]
554
                                 + t[x   ] * v_weights[1]
555
                                 + t[x+8 ] * v_weights[2]
556
                                 + t[x+16] * v_weights[3] + 64) >> 7);
557
        }
558
        dst += stride;
559
        t += 8;
560
    }
561
}
562

    
563
static void vp6_filter(vp56_context_t *s, uint8_t *dst, uint8_t *src,
564
                       int offset1, int offset2, int stride,
565
                       vp56_mv_t mv, int mask, int select, int luma)
566
{
567
    int filter4 = 0;
568
    int x8 = mv.x & mask;
569
    int y8 = mv.y & mask;
570

    
571
    if (luma) {
572
        x8 *= 2;
573
        y8 *= 2;
574
        filter4 = s->filter_mode;
575
        if (filter4 == 2) {
576
            if (s->max_vector_length &&
577
                (FFABS(mv.x) > s->max_vector_length ||
578
                 FFABS(mv.y) > s->max_vector_length)) {
579
                filter4 = 0;
580
            } else if (s->sample_variance_threshold
581
                       && (vp6_block_variance(src+offset1, stride)
582
                           < s->sample_variance_threshold)) {
583
                filter4 = 0;
584
            }
585
        }
586
    }
587

    
588
    if ((y8 && (offset2-offset1)*s->flip<0) || (!y8 && offset1 > offset2)) {
589
        offset1 = offset2;
590
    }
591

    
592
    if (filter4) {
593
        if (!y8) {                      /* left or right combine */
594
            vp6_filter_hv4(dst, src+offset1, stride, 1,
595
                           vp6_block_copy_filter[select][x8]);
596
        } else if (!x8) {               /* above or below combine */
597
            vp6_filter_hv4(dst, src+offset1, stride, stride,
598
                           vp6_block_copy_filter[select][y8]);
599
        } else {
600
            vp6_filter_diag4(dst, src+offset1 + ((mv.x^mv.y)>>31), stride,
601
                             vp6_block_copy_filter[select][x8],
602
                             vp6_block_copy_filter[select][y8]);
603
        }
604
    } else {
605
        if (!x8 || !y8) {
606
            s->dsp.put_h264_chroma_pixels_tab[0](dst, src+offset1, stride, 8, x8, y8);
607
        } else {
608
            vp6_filter_diag2(s, dst, src+offset1 + ((mv.x^mv.y)>>31), stride, x8, y8);
609
        }
610
    }
611
}
612

    
613
static int vp6_decode_init(AVCodecContext *avctx)
614
{
615
    vp56_context_t *s = avctx->priv_data;
616

    
617
    vp56_init(avctx, avctx->codec->id == CODEC_ID_VP6,
618
                     avctx->codec->id == CODEC_ID_VP6A);
619
    s->vp56_coord_div = vp6_coord_div;
620
    s->parse_vector_adjustment = vp6_parse_vector_adjustment;
621
    s->adjust = vp6_adjust;
622
    s->filter = vp6_filter;
623
    s->default_models_init = vp6_default_models_init;
624
    s->parse_vector_models = vp6_parse_vector_models;
625
    s->parse_coeff_models = vp6_parse_coeff_models;
626
    s->parse_header = vp6_parse_header;
627

    
628
    return 0;
629
}
630

    
631
AVCodec vp6_decoder = {
632
    "vp6",
633
    CODEC_TYPE_VIDEO,
634
    CODEC_ID_VP6,
635
    sizeof(vp56_context_t),
636
    vp6_decode_init,
637
    NULL,
638
    vp56_free,
639
    vp56_decode_frame,
640
    CODEC_CAP_DR1,
641
};
642

    
643
/* flash version, not flipped upside-down */
644
AVCodec vp6f_decoder = {
645
    "vp6f",
646
    CODEC_TYPE_VIDEO,
647
    CODEC_ID_VP6F,
648
    sizeof(vp56_context_t),
649
    vp6_decode_init,
650
    NULL,
651
    vp56_free,
652
    vp56_decode_frame,
653
    CODEC_CAP_DR1,
654
};
655

    
656
/* flash version, not flipped upside-down, with alpha channel */
657
AVCodec vp6a_decoder = {
658
    "vp6a",
659
    CODEC_TYPE_VIDEO,
660
    CODEC_ID_VP6A,
661
    sizeof(vp56_context_t),
662
    vp6_decode_init,
663
    NULL,
664
    vp56_free,
665
    vp56_decode_frame,
666
    CODEC_CAP_DR1,
667
};