GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/mdec.c Lines: 108 114 94.7 %
Date: 2020-11-28 20:53:16 Branches: 30 36 83.3 %

Line Branch Exec Source
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/*
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 * Sony PlayStation MDEC (Motion DECoder)
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 * Copyright (c) 2003 Michael Niedermayer
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 *
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 * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl>
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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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/**
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 * @file
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 * Sony PlayStation MDEC (Motion DECoder)
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 * This is very similar to intra-only MPEG-1.
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 */
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#include "avcodec.h"
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#include "blockdsp.h"
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#include "bswapdsp.h"
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#include "idctdsp.h"
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#include "mpeg12.h"
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#include "thread.h"
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typedef struct MDECContext {
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    AVCodecContext *avctx;
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    BlockDSPContext bdsp;
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    BswapDSPContext bbdsp;
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    IDCTDSPContext idsp;
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    ThreadFrame frame;
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    GetBitContext gb;
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    ScanTable scantable;
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    int version;
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    int qscale;
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    int last_dc[3];
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    int mb_width;
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    int mb_height;
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    int mb_x, mb_y;
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    DECLARE_ALIGNED(32, int16_t, block)[6][64];
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    DECLARE_ALIGNED(16, uint16_t, quant_matrix)[64];
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    uint8_t *bitstream_buffer;
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    unsigned int bitstream_buffer_size;
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    int block_last_index[6];
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} MDECContext;
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//very similar to MPEG-1
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285689
static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
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{
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    int level, diff, i, j, run;
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    int component;
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285689
    RLTable *rl = &ff_rl_mpeg1;
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285689
    uint8_t * const scantable = a->scantable.permutated;
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285689
    const uint16_t *quant_matrix = a->quant_matrix;
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285689
    const int qscale = a->qscale;
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    /* DC coefficient */
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285689
    if (a->version == 2) {
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214889
        block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
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    } else {
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70800
        component = (n <= 3 ? 0 : n - 4 + 1);
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70800
        diff = decode_dc(&a->gb, component);
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70800
        a->last_dc[component] += diff;
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70800
        block[0] = a->last_dc[component] * (1 << 3);
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    }
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285689
    i = 0;
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    {
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285689
        OPEN_READER(re, &a->gb);
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        /* now quantify & encode AC coefficients */
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        for (;;) {
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2462289
            UPDATE_CACHE(re, &a->gb);
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2462289
            GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
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2462289
            if (level == 127) {
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285688
                break;
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2176601
            } else if (level != 0) {
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2133703
                i += run;
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2133703
                if (i > 63) {
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1
                    av_log(a->avctx, AV_LOG_ERROR,
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                           "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
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1
                    return AVERROR_INVALIDDATA;
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                }
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2133702
                j     = scantable[i];
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2133702
                level = (level * qscale * quant_matrix[j]) >> 3;
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2133702
                level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
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2133702
                LAST_SKIP_BITS(re, &a->gb, 1);
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            } else {
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                /* escape */
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42898
                run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
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42898
                UPDATE_CACHE(re, &a->gb);
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42898
                level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
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42898
                i += run;
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42898
                if (i > 63) {
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                    av_log(a->avctx, AV_LOG_ERROR,
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                           "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
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                    return AVERROR_INVALIDDATA;
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                }
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42898
                j = scantable[i];
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42898
                if (level < 0) {
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24818
                    level = -level;
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24818
                    level = (level * (unsigned)qscale * quant_matrix[j]) >> 3;
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24818
                    level = (level - 1) | 1;
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24818
                    level = -level;
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                } else {
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18080
                    level = (level * (unsigned)qscale * quant_matrix[j]) >> 3;
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18080
                    level = (level - 1) | 1;
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                }
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            }
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2176600
            block[j] = level;
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        }
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285688
        CLOSE_READER(re, &a->gb);
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    }
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285688
    a->block_last_index[n] = i;
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285688
    return 0;
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}
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47615
static inline int decode_mb(MDECContext *a, int16_t block[6][64])
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{
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    int i, ret;
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    static const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
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47615
    a->bdsp.clear_blocks(block[0]);
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333303
    for (i = 0; i < 6; i++) {
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285689
        if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
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                                           block_index[i])) < 0)
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1
            return ret;
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285688
        if (get_bits_left(&a->gb) < 0)
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            return AVERROR_INVALIDDATA;
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    }
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47614
    return 0;
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}
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47614
static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
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{
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47614
    int16_t (*block)[64] = a->block;
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47614
    int linesize = frame->linesize[0];
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47614
    uint8_t *dest_y  = frame->data[0] + (mb_y * 16* linesize              ) + mb_x * 16;
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47614
    uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
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47614
    uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
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47614
    a->idsp.idct_put(dest_y,                    linesize, block[0]);
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47614
    a->idsp.idct_put(dest_y + 8,                linesize, block[1]);
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47614
    a->idsp.idct_put(dest_y + 8 * linesize,     linesize, block[2]);
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47614
    a->idsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
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47614
    if (!(a->avctx->flags & AV_CODEC_FLAG_GRAY)) {
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47614
        a->idsp.idct_put(dest_cb, frame->linesize[1], block[4]);
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47614
        a->idsp.idct_put(dest_cr, frame->linesize[2], block[5]);
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    }
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47614
}
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static int decode_frame(AVCodecContext *avctx,
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                        void *data, int *got_frame,
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                        AVPacket *avpkt)
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{
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    MDECContext * const a = avctx->priv_data;
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    const uint8_t *buf    = avpkt->data;
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    int buf_size          = avpkt->size;
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    ThreadFrame frame     = { .f = data };
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    int ret;
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    if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
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        return ret;
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    frame.f->pict_type = AV_PICTURE_TYPE_I;
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    frame.f->key_frame = 1;
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    av_fast_padded_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size, buf_size);
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    if (!a->bitstream_buffer)
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        return AVERROR(ENOMEM);
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    a->bbdsp.bswap16_buf((uint16_t *)a->bitstream_buffer, (uint16_t *)buf, (buf_size + 1) / 2);
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    if ((ret = init_get_bits8(&a->gb, a->bitstream_buffer, buf_size)) < 0)
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        return ret;
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    /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
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    skip_bits(&a->gb, 32);
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    a->qscale  = get_bits(&a->gb, 16);
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    a->version = get_bits(&a->gb, 16);
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    a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
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3932
    for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
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51353
        for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
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47615
            if ((ret = decode_mb(a, a->block)) < 0)
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1
                return ret;
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47614
            idct_put(a, frame.f, a->mb_x, a->mb_y);
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        }
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    }
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    *got_frame = 1;
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    return (get_bits_count(&a->gb) + 31) / 32 * 4;
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}
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7
static av_cold int decode_init(AVCodecContext *avctx)
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{
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    MDECContext * const a = avctx->priv_data;
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    int i;
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    a->mb_width  = (avctx->coded_width  + 15) / 16;
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    a->mb_height = (avctx->coded_height + 15) / 16;
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    a->avctx           = avctx;
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    ff_blockdsp_init(&a->bdsp, avctx);
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7
    ff_bswapdsp_init(&a->bbdsp);
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    ff_idctdsp_init(&a->idsp, avctx);
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    ff_mpeg12_init_vlcs();
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7
    ff_init_scantable(a->idsp.idct_permutation, &a->scantable,
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                      ff_zigzag_direct);
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    avctx->pix_fmt  = AV_PIX_FMT_YUVJ420P;
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    avctx->color_range = AVCOL_RANGE_JPEG;
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    /* init q matrix */
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455
    for (i = 0; i < 64; i++) {
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448
        int j = a->idsp.idct_permutation[i];
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        a->quant_matrix[j] = ff_mpeg1_default_intra_matrix[i];
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    }
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    return 0;
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}
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static av_cold int decode_end(AVCodecContext *avctx)
242
{
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7
    MDECContext * const a = avctx->priv_data;
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245
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    av_freep(&a->bitstream_buffer);
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7
    a->bitstream_buffer_size = 0;
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248
7
    return 0;
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}
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AVCodec ff_mdec_decoder = {
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    .name             = "mdec",
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    .long_name        = NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
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    .type             = AVMEDIA_TYPE_VIDEO,
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    .id               = AV_CODEC_ID_MDEC,
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    .priv_data_size   = sizeof(MDECContext),
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    .init             = decode_init,
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    .close            = decode_end,
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    .decode           = decode_frame,
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    .capabilities     = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
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};