LCOV - code coverage report
Current view: top level - libavformat - aacdec.c (source / functions) Hit Total Coverage
Test: coverage.info Lines: 83 96 86.5 %
Date: 2018-05-20 11:54:08 Functions: 4 4 100.0 %

          Line data    Source code
       1             : /*
       2             :  * raw ADTS AAC demuxer
       3             :  * Copyright (c) 2008 Michael Niedermayer <michaelni@gmx.at>
       4             :  * Copyright (c) 2009 Robert Swain ( rob opendot cl )
       5             :  *
       6             :  * This file is part of FFmpeg.
       7             :  *
       8             :  * FFmpeg is free software; you can redistribute it and/or
       9             :  * modify it under the terms of the GNU Lesser General Public
      10             :  * License as published by the Free Software Foundation; either
      11             :  * version 2.1 of the License, or (at your option) any later version.
      12             :  *
      13             :  * FFmpeg is distributed in the hope that it will be useful,
      14             :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
      15             :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      16             :  * Lesser General Public License for more details.
      17             :  *
      18             :  * You should have received a copy of the GNU Lesser General Public
      19             :  * License along with FFmpeg; if not, write to the Free Software
      20             :  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
      21             :  */
      22             : 
      23             : #include "libavutil/intreadwrite.h"
      24             : #include "avformat.h"
      25             : #include "avio_internal.h"
      26             : #include "internal.h"
      27             : #include "id3v1.h"
      28             : #include "id3v2.h"
      29             : #include "apetag.h"
      30             : 
      31             : #define ADTS_HEADER_SIZE 7
      32             : 
      33        6217 : static int adts_aac_probe(AVProbeData *p)
      34             : {
      35        6217 :     int max_frames = 0, first_frames = 0;
      36             :     int fsize, frames;
      37        6217 :     const uint8_t *buf0 = p->buf;
      38             :     const uint8_t *buf2;
      39             :     const uint8_t *buf;
      40        6217 :     const uint8_t *end = buf0 + p->buf_size - 7;
      41             : 
      42        6217 :     buf = buf0;
      43             : 
      44    87060526 :     for (; buf < end; buf = buf2 + 1) {
      45    87054309 :         buf2 = buf;
      46             : 
      47    87067889 :         for (frames = 0; buf2 < end; frames++) {
      48    87066139 :             uint32_t header = AV_RB16(buf2);
      49    87066139 :             if ((header & 0xFFF6) != 0xFFF0) {
      50    87052409 :                 if (buf != buf0) {
      51             :                     // Found something that isn't an ADTS header, starting
      52             :                     // from a position other than the start of the buffer.
      53             :                     // Discard the count we've accumulated so far since it
      54             :                     // probably was a false positive.
      55    87046220 :                     frames = 0;
      56             :                 }
      57    87052409 :                 break;
      58             :             }
      59       13730 :             fsize = (AV_RB32(buf2 + 3) >> 13) & 0x1FFF;
      60       13730 :             if (fsize < 7)
      61         150 :                 break;
      62       13580 :             fsize = FFMIN(fsize, end - buf2);
      63       13580 :             buf2 += fsize;
      64             :         }
      65    87054309 :         max_frames = FFMAX(max_frames, frames);
      66    87054309 :         if (buf == buf0)
      67        6217 :             first_frames = frames;
      68             :     }
      69             : 
      70        6217 :     if (first_frames >= 3)
      71          26 :         return AVPROBE_SCORE_EXTENSION + 1;
      72        6191 :     else if (max_frames > 100)
      73           0 :         return AVPROBE_SCORE_EXTENSION;
      74        6191 :     else if (max_frames >= 3)
      75           0 :         return AVPROBE_SCORE_EXTENSION / 2;
      76        6191 :     else if (first_frames >= 1)
      77           2 :         return 1;
      78             :     else
      79        6189 :         return 0;
      80             : }
      81             : 
      82          30 : static int adts_aac_read_header(AVFormatContext *s)
      83             : {
      84             :     AVStream *st;
      85             :     uint16_t state;
      86             : 
      87          30 :     st = avformat_new_stream(s, NULL);
      88          30 :     if (!st)
      89           0 :         return AVERROR(ENOMEM);
      90             : 
      91          30 :     st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
      92          30 :     st->codecpar->codec_id   = s->iformat->raw_codec_id;
      93          30 :     st->need_parsing         = AVSTREAM_PARSE_FULL_RAW;
      94             : 
      95          30 :     ff_id3v1_read(s);
      96          60 :     if ((s->pb->seekable & AVIO_SEEKABLE_NORMAL) &&
      97          30 :         !av_dict_get(s->metadata, "", NULL, AV_DICT_IGNORE_SUFFIX)) {
      98          29 :         int64_t cur = avio_tell(s->pb);
      99          29 :         ff_ape_parse_tag(s);
     100          29 :         avio_seek(s->pb, cur, SEEK_SET);
     101             :     }
     102             : 
     103             :     // skip data until the first ADTS frame is found
     104          30 :     state = avio_r8(s->pb);
     105         313 :     while (!avio_feof(s->pb) && avio_tell(s->pb) < s->probesize) {
     106         283 :         state = (state << 8) | avio_r8(s->pb);
     107         283 :         if ((state >> 4) != 0xFFF)
     108         253 :             continue;
     109          30 :         avio_seek(s->pb, -2, SEEK_CUR);
     110          30 :         break;
     111             :     }
     112          30 :     if ((state >> 4) != 0xFFF)
     113           0 :         return AVERROR_INVALIDDATA;
     114             : 
     115             :     // LCM of all possible ADTS sample rates
     116          30 :     avpriv_set_pts_info(st, 64, 1, 28224000);
     117             : 
     118          30 :     return 0;
     119             : }
     120             : 
     121           3 : static int handle_id3(AVFormatContext *s, AVPacket *pkt)
     122             : {
     123           3 :     AVDictionary *metadata = NULL;
     124             :     AVIOContext ioctx;
     125           3 :     ID3v2ExtraMeta *id3v2_extra_meta = NULL;
     126             :     int ret;
     127             : 
     128           3 :     ret = av_append_packet(s->pb, pkt, ff_id3v2_tag_len(pkt->data) - pkt->size);
     129           3 :     if (ret < 0) {
     130           0 :         av_packet_unref(pkt);
     131           0 :         return ret;
     132             :     }
     133             : 
     134           3 :     ffio_init_context(&ioctx, pkt->data, pkt->size, 0, NULL, NULL, NULL, NULL);
     135           3 :     ff_id3v2_read_dict(&ioctx, &metadata, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta);
     136           3 :     if ((ret = ff_id3v2_parse_priv_dict(&metadata, &id3v2_extra_meta)) < 0)
     137           0 :         goto error;
     138             : 
     139           3 :     if (metadata) {
     140           3 :         if ((ret = av_dict_copy(&s->metadata, metadata, 0)) < 0)
     141           0 :             goto error;
     142           3 :         s->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
     143             :     }
     144             : 
     145           3 : error:
     146           3 :     av_packet_unref(pkt);
     147           3 :     ff_id3v2_free_extra_meta(&id3v2_extra_meta);
     148           3 :     av_dict_free(&metadata);
     149             : 
     150           3 :     return ret;
     151             : }
     152             : 
     153        5818 : static int adts_aac_read_packet(AVFormatContext *s, AVPacket *pkt)
     154             : {
     155             :     int ret, fsize;
     156             : 
     157             :     // Parse all the ID3 headers between frames
     158             :     while (1) {
     159        5821 :         ret = av_get_packet(s->pb, pkt, FFMAX(ID3v2_HEADER_SIZE, ADTS_HEADER_SIZE));
     160        5818 :         if (ret >= ID3v2_HEADER_SIZE && ff_id3v2_match(pkt->data, ID3v2_DEFAULT_MAGIC)) {
     161           3 :             if ((ret = handle_id3(s, pkt)) >= 0) {
     162           3 :                 continue;
     163             :             }
     164             :         }
     165        5815 :         break;
     166             :     }
     167             : 
     168        5815 :     if (ret < 0)
     169          42 :         return ret;
     170             : 
     171        5773 :     if (ret < ADTS_HEADER_SIZE) {
     172           0 :         av_packet_unref(pkt);
     173           0 :         return AVERROR(EIO);
     174             :     }
     175             : 
     176        5773 :     if ((AV_RB16(pkt->data) >> 4) != 0xfff) {
     177           2 :         av_packet_unref(pkt);
     178           2 :         return AVERROR_INVALIDDATA;
     179             :     }
     180             : 
     181        5771 :     fsize = (AV_RB32(pkt->data + 3) >> 13) & 0x1FFF;
     182        5771 :     if (fsize < ADTS_HEADER_SIZE) {
     183           0 :         av_packet_unref(pkt);
     184           0 :         return AVERROR_INVALIDDATA;
     185             :     }
     186             : 
     187        5771 :     ret = av_append_packet(s->pb, pkt, fsize - pkt->size);
     188        5771 :     if (ret < 0)
     189           0 :         av_packet_unref(pkt);
     190             : 
     191        5771 :     return ret;
     192             : }
     193             : 
     194             : AVInputFormat ff_aac_demuxer = {
     195             :     .name         = "aac",
     196             :     .long_name    = NULL_IF_CONFIG_SMALL("raw ADTS AAC (Advanced Audio Coding)"),
     197             :     .read_probe   = adts_aac_probe,
     198             :     .read_header  = adts_aac_read_header,
     199             :     .read_packet  = adts_aac_read_packet,
     200             :     .flags        = AVFMT_GENERIC_INDEX,
     201             :     .extensions   = "aac",
     202             :     .mime_type    = "audio/aac,audio/aacp,audio/x-aac",
     203             :     .raw_codec_id = AV_CODEC_ID_AAC,
     204             : };

Generated by: LCOV version 1.13