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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 "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(VP56Context *s);
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static void vp6_parse_coeff_huffman(VP56Context *s);
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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 (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 (buf_size < 0)
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            return 0;
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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<<3);
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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(VP56Context *s)
155
{
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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(VP56Context *s)
166
{
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    VP56Model *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(VP56Context *s)
184
{
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    VP56RangeCoder *c = &s->c;
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    VP56Model *model = s->modelp;
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    int comp, node;
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    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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/* nodes must ascend by count, but with descending symbol order */
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static int vp6_huff_cmp(const void *va, const void *vb)
209
{
210
    const Node *a = va, *b = vb;
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    return (a->count - b->count)*16 + (b->sym - a->sym);
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}
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static void vp6_build_huff_tree(VP56Context *s, uint8_t coeff_model[],
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                                const uint8_t *map, unsigned size, VLC *vlc)
216
{
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    Node nodes[2*size], *tmp = &nodes[size];
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    int a, b, i;
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    /* first compute probabilities from model */
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    tmp[0].count = 256;
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    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,
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                       FF_HUFFMAN_FLAG_HNODE_FIRST);
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}
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234
static void vp6_parse_coeff_models(VP56Context *s)
235
{
236
    VP56RangeCoder *c = &s->c;
237
    VP56Model *model = s->modelp;
238
    int def_prob[11];
239
    int node, cg, ctx, pos;
240
    int ct;    /* code type */
241
    int pt;    /* plane type (0 for Y, 1 for U or V) */
242

    
243
    memset(def_prob, 0x80, sizeof(def_prob));
244

    
245
    for (pt=0; pt<2; pt++)
246
        for (node=0; node<11; node++)
247
            if (vp56_rac_get_prob(c, vp6_dccv_pct[pt][node])) {
248
                def_prob[node] = vp56_rac_gets_nn(c, 7);
249
                model->coeff_dccv[pt][node] = def_prob[node];
250
            } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
251
                model->coeff_dccv[pt][node] = def_prob[node];
252
            }
253

    
254
    if (vp56_rac_get(c)) {
255
        for (pos=1; pos<64; pos++)
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            if (vp56_rac_get_prob(c, vp6_coeff_reorder_pct[pos]))
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                model->coeff_reorder[pos] = vp56_rac_gets(c, 4);
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        vp6_coeff_order_table_init(s);
259
    }
260

    
261
    for (cg=0; cg<2; cg++)
262
        for (node=0; node<14; node++)
263
            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);
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266
    for (ct=0; ct<3; ct++)
267
        for (pt=0; pt<2; pt++)
268
            for (cg=0; cg<6; cg++)
269
                for (node=0; node<11; node++)
270
                    if (vp56_rac_get_prob(c, vp6_ract_pct[ct][pt][cg][node])) {
271
                        def_prob[node] = vp56_rac_gets_nn(c, 7);
272
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
273
                    } else if (s->framep[VP56_FRAME_CURRENT]->key_frame) {
274
                        model->coeff_ract[pt][ct][cg][node] = def_prob[node];
275
                    }
276

    
277
    if (s->use_huffman) {
278
        for (pt=0; pt<2; pt++) {
279
            vp6_build_huff_tree(s, model->coeff_dccv[pt],
280
                                vp6_huff_coeff_map, 12, &s->dccv_vlc[pt]);
281
            vp6_build_huff_tree(s, model->coeff_runv[pt],
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                                vp6_huff_run_map, 9, &s->runv_vlc[pt]);
283
            for (ct=0; ct<3; ct++)
284
                for (cg = 0; cg < 6; cg++)
285
                    vp6_build_huff_tree(s, model->coeff_ract[pt][ct][cg],
286
                                        vp6_huff_coeff_map, 12,
287
                                        &s->ract_vlc[pt][ct][cg]);
288
        }
289
        memset(s->nb_null, 0, sizeof(s->nb_null));
290
    } else {
291
    /* coeff_dcct is a linear combination of coeff_dccv */
292
    for (pt=0; pt<2; pt++)
293
        for (ctx=0; ctx<3; ctx++)
294
            for (node=0; node<5; node++)
295
                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);
296
    }
297
}
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299
static void vp6_parse_vector_adjustment(VP56Context *s, VP56mv *vect)
300
{
301
    VP56RangeCoder *c = &s->c;
302
    VP56Model *model = s->modelp;
303
    int comp;
304

    
305
    *vect = (VP56mv) {0,0};
306
    if (s->vector_candidate_pos < 2)
307
        *vect = s->vector_candidate[0];
308

    
309
    for (comp=0; comp<2; comp++) {
310
        int i, delta = 0;
311

    
312
        if (vp56_rac_get_prob(c, model->vector_dct[comp])) {
313
            static const uint8_t prob_order[] = {0, 1, 2, 7, 6, 5, 4};
314
            for (i=0; i<sizeof(prob_order); i++) {
315
                int j = prob_order[i];
316
                delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][j])<<j;
317
            }
318
            if (delta & 0xF0)
319
                delta |= vp56_rac_get_prob(c, model->vector_fdv[comp][3])<<3;
320
            else
321
                delta |= 8;
322
        } else {
323
            delta = vp56_rac_get_tree(c, vp56_pva_tree,
324
                                      model->vector_pdv[comp]);
325
        }
326

    
327
        if (delta && vp56_rac_get_prob(c, model->vector_sig[comp]))
328
            delta = -delta;
329

    
330
        if (!comp)
331
            vect->x += delta;
332
        else
333
            vect->y += delta;
334
    }
335
}
336

    
337
/**
338
 * Read number of consecutive blocks with null DC or AC.
339
 * This value is < 74.
340
 */
341
static unsigned vp6_get_nb_null(VP56Context *s)
342
{
343
    unsigned val = get_bits(&s->gb, 2);
344
    if (val == 2)
345
        val += get_bits(&s->gb, 2);
346
    else if (val == 3) {
347
        val = get_bits1(&s->gb) << 2;
348
        val = 6+val + get_bits(&s->gb, 2+val);
349
    }
350
    return val;
351
}
352

    
353
static void vp6_parse_coeff_huffman(VP56Context *s)
354
{
355
    VP56Model *model = s->modelp;
356
    uint8_t *permute = s->scantable.permutated;
357
    VLC *vlc_coeff;
358
    int coeff, sign, coeff_idx;
359
    int b, cg, idx;
360
    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
361

    
362
    for (b=0; b<6; b++) {
363
        int ct = 0;    /* code type */
364
        if (b > 3) pt = 1;
365
        vlc_coeff = &s->dccv_vlc[pt];
366

    
367
        for (coeff_idx=0; coeff_idx<64; ) {
368
            int run = 1;
369
            if (coeff_idx<2 && s->nb_null[coeff_idx][pt]) {
370
                s->nb_null[coeff_idx][pt]--;
371
                if (coeff_idx)
372
                    break;
373
            } else {
374
                coeff = get_vlc2(&s->gb, vlc_coeff->table, 9, 3);
375
                if (coeff == 0) {
376
                    if (coeff_idx) {
377
                        int pt = (coeff_idx >= 6);
378
                        run += get_vlc2(&s->gb, s->runv_vlc[pt].table, 9, 3);
379
                        if (run >= 9)
380
                            run += get_bits(&s->gb, 6);
381
                    } else
382
                        s->nb_null[0][pt] = vp6_get_nb_null(s);
383
                    ct = 0;
384
                } else if (coeff == 11) {  /* end of block */
385
                    if (coeff_idx == 1)    /* first AC coeff ? */
386
                        s->nb_null[1][pt] = vp6_get_nb_null(s);
387
                    break;
388
                } else {
389
                    int coeff2 = vp56_coeff_bias[coeff];
390
                    if (coeff > 4)
391
                        coeff2 += get_bits(&s->gb, coeff <= 9 ? coeff - 4 : 11);
392
                    ct = 1 + (coeff2 > 1);
393
                    sign = get_bits1(&s->gb);
394
                    coeff2 = (coeff2 ^ -sign) + sign;
395
                    if (coeff_idx)
396
                        coeff2 *= s->dequant_ac;
397
                    idx = model->coeff_index_to_pos[coeff_idx];
398
                    s->block_coeff[b][permute[idx]] = coeff2;
399
                }
400
            }
401
            coeff_idx+=run;
402
            cg = FFMIN(vp6_coeff_groups[coeff_idx], 3);
403
            vlc_coeff = &s->ract_vlc[pt][ct][cg];
404
        }
405
    }
406
}
407

    
408
static void vp6_parse_coeff(VP56Context *s)
409
{
410
    VP56RangeCoder *c = s->ccp;
411
    VP56Model *model = s->modelp;
412
    uint8_t *permute = s->scantable.permutated;
413
    uint8_t *model1, *model2, *model3;
414
    int coeff, sign, coeff_idx;
415
    int b, i, cg, idx, ctx;
416
    int pt = 0;    /* plane type (0 for Y, 1 for U or V) */
417

    
418
    for (b=0; b<6; b++) {
419
        int ct = 1;    /* code type */
420
        int run = 1;
421

    
422
        if (b > 3) pt = 1;
423

    
424
        ctx = s->left_block[vp56_b6to4[b]].not_null_dc
425
              + s->above_blocks[s->above_block_idx[b]].not_null_dc;
426
        model1 = model->coeff_dccv[pt];
427
        model2 = model->coeff_dcct[pt][ctx];
428

    
429
        for (coeff_idx=0; coeff_idx<64; ) {
430
            if ((coeff_idx>1 && ct==0) || vp56_rac_get_prob(c, model2[0])) {
431
                /* parse a coeff */
432
                if (vp56_rac_get_prob(c, model2[2])) {
433
                    if (vp56_rac_get_prob(c, model2[3])) {
434
                        idx = vp56_rac_get_tree(c, vp56_pc_tree, model1);
435
                        coeff = vp56_coeff_bias[idx+5];
436
                        for (i=vp56_coeff_bit_length[idx]; i>=0; i--)
437
                            coeff += vp56_rac_get_prob(c, vp56_coeff_parse_table[idx][i]) << i;
438
                    } else {
439
                        if (vp56_rac_get_prob(c, model2[4]))
440
                            coeff = 3 + vp56_rac_get_prob(c, model1[5]);
441
                        else
442
                            coeff = 2;
443
                    }
444
                    ct = 2;
445
                } else {
446
                    ct = 1;
447
                    coeff = 1;
448
                }
449
                sign = vp56_rac_get(c);
450
                coeff = (coeff ^ -sign) + sign;
451
                if (coeff_idx)
452
                    coeff *= s->dequant_ac;
453
                idx = model->coeff_index_to_pos[coeff_idx];
454
                s->block_coeff[b][permute[idx]] = coeff;
455
                run = 1;
456
            } else {
457
                /* parse a run */
458
                ct = 0;
459
                if (coeff_idx > 0) {
460
                    if (!vp56_rac_get_prob(c, model2[1]))
461
                        break;
462

    
463
                    model3 = model->coeff_runv[coeff_idx >= 6];
464
                    run = vp56_rac_get_tree(c, vp6_pcr_tree, model3);
465
                    if (!run)
466
                        for (run=9, i=0; i<6; i++)
467
                            run += vp56_rac_get_prob(c, model3[i+8]) << i;
468
                }
469
            }
470

    
471
            cg = vp6_coeff_groups[coeff_idx+=run];
472
            model1 = model2 = model->coeff_ract[pt][ct][cg];
473
        }
474

    
475
        s->left_block[vp56_b6to4[b]].not_null_dc =
476
        s->above_blocks[s->above_block_idx[b]].not_null_dc = !!s->block_coeff[b][0];
477
    }
478
}
479

    
480
static int vp6_adjust(int v, int t)
481
{
482
    int V = v, s = v >> 31;
483
    V ^= s;
484
    V -= s;
485
    if (V-t-1 >= (unsigned)(t-1))
486
        return v;
487
    V = 2*t - V;
488
    V += s;
489
    V ^= s;
490
    return V;
491
}
492

    
493
static int vp6_block_variance(uint8_t *src, int stride)
494
{
495
    int sum = 0, square_sum = 0;
496
    int y, x;
497

    
498
    for (y=0; y<8; y+=2) {
499
        for (x=0; x<8; x+=2) {
500
            sum += src[x];
501
            square_sum += src[x]*src[x];
502
        }
503
        src += 2*stride;
504
    }
505
    return (16*square_sum - sum*sum) >> 8;
506
}
507

    
508
static void vp6_filter_hv4(uint8_t *dst, uint8_t *src, int stride,
509
                           int delta, const int16_t *weights)
510
{
511
    int x, y;
512

    
513
    for (y=0; y<8; y++) {
514
        for (x=0; x<8; x++) {
515
            dst[x] = av_clip_uint8((  src[x-delta  ] * weights[0]
516
                                 + src[x        ] * weights[1]
517
                                 + src[x+delta  ] * weights[2]
518
                                 + src[x+2*delta] * weights[3] + 64) >> 7);
519
        }
520
        src += stride;
521
        dst += stride;
522
    }
523
}
524

    
525
static void vp6_filter_diag2(VP56Context *s, uint8_t *dst, uint8_t *src,
526
                             int stride, int h_weight, int v_weight)
527
{
528
    uint8_t *tmp = s->edge_emu_buffer+16;
529
    s->dsp.put_h264_chroma_pixels_tab[0](tmp, src, stride, 9, h_weight, 0);
530
    s->dsp.put_h264_chroma_pixels_tab[0](dst, tmp, stride, 8, 0, v_weight);
531
}
532

    
533
static void vp6_filter_diag4(uint8_t *dst, uint8_t *src, int stride,
534
                             const int16_t *h_weights,const int16_t *v_weights)
535
{
536
    int x, y;
537
    int tmp[8*11];
538
    int *t = tmp;
539

    
540
    src -= stride;
541

    
542
    for (y=0; y<11; y++) {
543
        for (x=0; x<8; x++) {
544
            t[x] = av_clip_uint8((  src[x-1] * h_weights[0]
545
                               + src[x  ] * h_weights[1]
546
                               + src[x+1] * h_weights[2]
547
                               + src[x+2] * h_weights[3] + 64) >> 7);
548
        }
549
        src += stride;
550
        t += 8;
551
    }
552

    
553
    t = tmp + 8;
554
    for (y=0; y<8; y++) {
555
        for (x=0; x<8; x++) {
556
            dst[x] = av_clip_uint8((  t[x-8 ] * v_weights[0]
557
                                 + t[x   ] * v_weights[1]
558
                                 + t[x+8 ] * v_weights[2]
559
                                 + t[x+16] * v_weights[3] + 64) >> 7);
560
        }
561
        dst += stride;
562
        t += 8;
563
    }
564
}
565

    
566
static void vp6_filter(VP56Context *s, uint8_t *dst, uint8_t *src,
567
                       int offset1, int offset2, int stride,
568
                       VP56mv mv, int mask, int select, int luma)
569
{
570
    int filter4 = 0;
571
    int x8 = mv.x & mask;
572
    int y8 = mv.y & mask;
573

    
574
    if (luma) {
575
        x8 *= 2;
576
        y8 *= 2;
577
        filter4 = s->filter_mode;
578
        if (filter4 == 2) {
579
            if (s->max_vector_length &&
580
                (FFABS(mv.x) > s->max_vector_length ||
581
                 FFABS(mv.y) > s->max_vector_length)) {
582
                filter4 = 0;
583
            } else if (s->sample_variance_threshold
584
                       && (vp6_block_variance(src+offset1, stride)
585
                           < s->sample_variance_threshold)) {
586
                filter4 = 0;
587
            }
588
        }
589
    }
590

    
591
    if ((y8 && (offset2-offset1)*s->flip<0) || (!y8 && offset1 > offset2)) {
592
        offset1 = offset2;
593
    }
594

    
595
    if (filter4) {
596
        if (!y8) {                      /* left or right combine */
597
            vp6_filter_hv4(dst, src+offset1, stride, 1,
598
                           vp6_block_copy_filter[select][x8]);
599
        } else if (!x8) {               /* above or below combine */
600
            vp6_filter_hv4(dst, src+offset1, stride, stride,
601
                           vp6_block_copy_filter[select][y8]);
602
        } else {
603
            vp6_filter_diag4(dst, src+offset1 + ((mv.x^mv.y)>>31), stride,
604
                             vp6_block_copy_filter[select][x8],
605
                             vp6_block_copy_filter[select][y8]);
606
        }
607
    } else {
608
        if (!x8 || !y8) {
609
            s->dsp.put_h264_chroma_pixels_tab[0](dst, src+offset1, stride, 8, x8, y8);
610
        } else {
611
            vp6_filter_diag2(s, dst, src+offset1 + ((mv.x^mv.y)>>31), stride, x8, y8);
612
        }
613
    }
614
}
615

    
616
static av_cold int vp6_decode_init(AVCodecContext *avctx)
617
{
618
    VP56Context *s = avctx->priv_data;
619

    
620
    vp56_init(avctx, avctx->codec->id == CODEC_ID_VP6,
621
                     avctx->codec->id == CODEC_ID_VP6A);
622
    s->vp56_coord_div = vp6_coord_div;
623
    s->parse_vector_adjustment = vp6_parse_vector_adjustment;
624
    s->adjust = vp6_adjust;
625
    s->filter = vp6_filter;
626
    s->default_models_init = vp6_default_models_init;
627
    s->parse_vector_models = vp6_parse_vector_models;
628
    s->parse_coeff_models = vp6_parse_coeff_models;
629
    s->parse_header = vp6_parse_header;
630

    
631
    return 0;
632
}
633

    
634
AVCodec vp6_decoder = {
635
    "vp6",
636
    CODEC_TYPE_VIDEO,
637
    CODEC_ID_VP6,
638
    sizeof(VP56Context),
639
    vp6_decode_init,
640
    NULL,
641
    vp56_free,
642
    vp56_decode_frame,
643
    CODEC_CAP_DR1,
644
    .long_name = NULL_IF_CONFIG_SMALL("On2 VP6"),
645
};
646

    
647
/* flash version, not flipped upside-down */
648
AVCodec vp6f_decoder = {
649
    "vp6f",
650
    CODEC_TYPE_VIDEO,
651
    CODEC_ID_VP6F,
652
    sizeof(VP56Context),
653
    vp6_decode_init,
654
    NULL,
655
    vp56_free,
656
    vp56_decode_frame,
657
    CODEC_CAP_DR1,
658
    .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version)"),
659
};
660

    
661
/* flash version, not flipped upside-down, with alpha channel */
662
AVCodec vp6a_decoder = {
663
    "vp6a",
664
    CODEC_TYPE_VIDEO,
665
    CODEC_ID_VP6A,
666
    sizeof(VP56Context),
667
    vp6_decode_init,
668
    NULL,
669
    vp56_free,
670
    vp56_decode_frame,
671
    CODEC_CAP_DR1,
672
    .long_name = NULL_IF_CONFIG_SMALL("On2 VP6 (Flash version, with alpha channel)"),
673
};