GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/mpegaudio_parser.c Lines: 54 61 88.5 %
Date: 2019-11-20 04:07:19 Branches: 41 44 93.2 %

Line Branch Exec Source
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/*
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 * MPEG Audio parser
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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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#include "parser.h"
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#include "mpegaudiodecheader.h"
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#include "libavutil/common.h"
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#include "libavformat/apetag.h" // for APE tag.
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#include "libavformat/id3v1.h" // for ID3v1_TAG_SIZE
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typedef struct MpegAudioParseContext {
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    ParseContext pc;
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    int frame_size;
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    uint32_t header;
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    int header_count;
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    int no_bitrate;
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} MpegAudioParseContext;
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#define MPA_HEADER_SIZE 4
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/* header + layer + freq + lsf/mpeg25 */
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#define SAME_HEADER_MASK \
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   (0xffe00000 | (3 << 17) | (3 << 10) | (3 << 19))
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19126
static int mpegaudio_parse(AVCodecParserContext *s1,
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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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19126
    MpegAudioParseContext *s = s1->priv_data;
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19126
    ParseContext *pc = &s->pc;
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19126
    uint32_t state= pc->state;
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    int i;
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19126
    int next= END_NOT_FOUND;
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19126
    int flush = !buf_size;
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38526
    for(i=0; i<buf_size; ){
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35255
        if(s->frame_size){
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18777
            int inc= FFMIN(buf_size - i, s->frame_size);
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18777
            i += inc;
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18777
            s->frame_size -= inc;
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18777
            state = 0;
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18777
            if(!s->frame_size){
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15855
                next= i;
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15855
                break;
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            }
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        }else{
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199426
            while(i<buf_size){
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                int ret, sr, channels, bit_rate, frame_size;
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199178
                enum AVCodecID codec_id = avctx->codec_id;
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199178
                state= (state<<8) + buf[i++];
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199178
                ret = ff_mpa_decode_header(state, &sr, &channels, &frame_size, &bit_rate, &codec_id);
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199178
                if (ret < 4) {
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182948
                    if (i > 4)
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134251
                        s->header_count = -2;
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                } else {
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16230
                    int header_threshold = avctx->codec_id != AV_CODEC_ID_NONE && avctx->codec_id != codec_id;
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16230
                    if((state&SAME_HEADER_MASK) != (s->header&SAME_HEADER_MASK) && s->header)
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17
                        s->header_count= -3;
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16230
                    s->header= state;
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16230
                    s->header_count++;
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16230
                    s->frame_size = ret-4;
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16230
                    if (s->header_count > header_threshold) {
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15942
                        avctx->sample_rate= sr;
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15942
                        avctx->channels   = channels;
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15942
                        s1->duration      = frame_size;
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15942
                        avctx->codec_id   = codec_id;
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15942
                        if (s->no_bitrate || !avctx->bit_rate) {
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11075
                            s->no_bitrate = 1;
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11075
                            avctx->bit_rate += (bit_rate - avctx->bit_rate) / (s->header_count - header_threshold);
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                        }
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                    }
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16230
                    if (s1->flags & PARSER_FLAG_COMPLETE_FRAMES) {
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                        s->frame_size = 0;
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                        next = buf_size;
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15979
                    } else if (codec_id == AV_CODEC_ID_MP3ADU) {
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                        avpriv_report_missing_feature(avctx,
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                            "MP3ADU full parser");
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                        *poutbuf = NULL;
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                        *poutbuf_size = 0;
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                        return buf_size; /* parsers must not return error codes */
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                    }
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16230
                    break;
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                }
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            }
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        }
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    }
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19126
    pc->state= state;
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19126
    if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
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2932
        *poutbuf = NULL;
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2932
        *poutbuf_size = 0;
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2932
        return buf_size;
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    }
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16194
    if (flush && buf_size >= ID3v1_TAG_SIZE && memcmp(buf, "TAG", 3) == 0) {
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        *poutbuf = NULL;
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        *poutbuf_size = 0;
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        return next;
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    }
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16189
    if (flush && buf_size >= APE_TAG_FOOTER_BYTES && memcmp(buf, APE_TAG_PREAMBLE, 8) == 0) {
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        *poutbuf = NULL;
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        *poutbuf_size = 0;
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        return next;
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    }
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16189
    *poutbuf = buf;
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16189
    *poutbuf_size = buf_size;
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16189
    return next;
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}
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AVCodecParser ff_mpegaudio_parser = {
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    .codec_ids      = { AV_CODEC_ID_MP1, AV_CODEC_ID_MP2, AV_CODEC_ID_MP3, AV_CODEC_ID_MP3ADU },
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    .priv_data_size = sizeof(MpegAudioParseContext),
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    .parser_parse   = mpegaudio_parse,
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    .parser_close   = ff_parse_close,
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};