GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/mpeg4video_parser.c Lines: 67 70 95.7 %
Date: 2019-11-22 03:34:36 Branches: 38 46 82.6 %

Line Branch Exec Source
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/*
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 * MPEG-4 video frame extraction
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 * Copyright (c) 2003 Fabrice Bellard
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 * Copyright (c) 2003 Michael Niedermayer
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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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#define UNCHECKED_BITSTREAM_READER 1
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#include "internal.h"
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#include "parser.h"
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#include "mpegvideo.h"
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#include "mpeg4video.h"
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#include "mpeg4video_parser.h"
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struct Mp4vParseContext {
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    ParseContext pc;
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    Mpeg4DecContext dec_ctx;
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    int first_picture;
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};
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8238
int ff_mpeg4_find_frame_end(ParseContext *pc, const uint8_t *buf, int buf_size)
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{
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    int vop_found, i;
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    uint32_t state;
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8238
    vop_found = pc->frame_start_found;
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8238
    state     = pc->state;
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8238
    i = 0;
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8238
    if (!vop_found) {
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8438
        for (i = 0; i < buf_size; i++) {
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8436
            state = (state << 8) | buf[i];
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8436
            if (state == VOP_STARTCODE) {
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1085
                i++;
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1085
                vop_found = 1;
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1085
                break;
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            }
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        }
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    }
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8238
    if (vop_found) {
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        /* EOF considered as end of frame */
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8236
        if (buf_size == 0)
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24
            return 0;
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8516208
        for (; i < buf_size; i++) {
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8509069
            state = (state << 8) | buf[i];
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8509069
            if ((state & 0xFFFFFF00) == 0x100) {
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1073
                if (state == SLICE_STARTCODE || state == EXT_STARTCODE)
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                    continue;
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1073
                pc->frame_start_found = 0;
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1073
                pc->state             = -1;
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1073
                return i - 3;
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            }
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        }
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    }
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7141
    pc->frame_start_found = vop_found;
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7141
    pc->state             = state;
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7141
    return END_NOT_FOUND;
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}
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/* XXX: make it use less memory */
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3549
static int mpeg4_decode_header(AVCodecParserContext *s1, AVCodecContext *avctx,
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                               const uint8_t *buf, int buf_size)
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{
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3549
    struct Mp4vParseContext *pc = s1->priv_data;
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3549
    Mpeg4DecContext *dec_ctx = &pc->dec_ctx;
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3549
    MpegEncContext *s = &dec_ctx->m;
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3549
    GetBitContext gb1, *gb = &gb1;
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    int ret;
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3549
    s->avctx               = avctx;
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3549
    s->current_picture_ptr = &s->current_picture;
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3549
    if (avctx->extradata_size && pc->first_picture) {
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241
        init_get_bits(gb, avctx->extradata, avctx->extradata_size * 8);
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        ret = ff_mpeg4_decode_picture_header(dec_ctx, gb, 1);
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        if (ret < 0)
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            av_log(avctx, AV_LOG_WARNING, "Failed to parse extradata\n");
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    }
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3549
    init_get_bits(gb, buf, 8 * buf_size);
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3549
    ret = ff_mpeg4_decode_picture_header(dec_ctx, gb, 0);
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3549
    if (s->width && (!avctx->width || !avctx->height ||
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3485
                     !avctx->coded_width || !avctx->coded_height)) {
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        ret = ff_set_dimensions(avctx, s->width, s->height);
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        if (ret < 0)
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            return ret;
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    }
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3549
    if((s1->flags & PARSER_FLAG_USE_CODEC_TS) && s->avctx->time_base.den>0 && ret>=0){
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        av_assert1(s1->pts == AV_NOPTS_VALUE);
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        av_assert1(s1->dts == AV_NOPTS_VALUE);
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874
        s1->pts = av_rescale_q(s->time, (AVRational){1, s->avctx->time_base.den}, (AVRational){1, 1200000});
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    }
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3549
    s1->pict_type     = s->pict_type;
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3549
    pc->first_picture = 0;
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3549
    return ret;
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}
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static av_cold int mpeg4video_parse_init(AVCodecParserContext *s)
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{
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    struct Mp4vParseContext *pc = s->priv_data;
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    ff_mpeg4videodec_static_init();
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    pc->first_picture           = 1;
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328
    pc->dec_ctx.m.quant_precision     = 5;
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328
    pc->dec_ctx.m.slice_context_count = 1;
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    pc->dec_ctx.showed_packed_warning = 1;
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    return 0;
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}
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10690
static int mpeg4video_parse(AVCodecParserContext *s,
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                            AVCodecContext *avctx,
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                            const uint8_t **poutbuf, int *poutbuf_size,
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                            const uint8_t *buf, int buf_size)
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{
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10690
    ParseContext *pc = s->priv_data;
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    int next;
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10690
    if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
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2452
        next = buf_size;
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    } else {
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8238
        next = ff_mpeg4_find_frame_end(pc, buf, buf_size);
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8238
        if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
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7141
            *poutbuf      = NULL;
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7141
            *poutbuf_size = 0;
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7141
            return buf_size;
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        }
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    }
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3549
    mpeg4_decode_header(s, avctx, buf, buf_size);
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3549
    *poutbuf      = buf;
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3549
    *poutbuf_size = buf_size;
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3549
    return next;
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}
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AVCodecParser ff_mpeg4video_parser = {
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    .codec_ids      = { AV_CODEC_ID_MPEG4 },
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    .priv_data_size = sizeof(struct Mp4vParseContext),
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    .parser_init    = mpeg4video_parse_init,
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    .parser_parse   = mpeg4video_parse,
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    .parser_close   = ff_parse_close,
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    .split          = ff_mpeg4video_split,
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};