RepoMirrors
/
ffmpeg
mirror of https://git.ffmpeg.org/ffmpeg.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

avformat/aacdec: add a custom read_packet function 

Atempt to read and propagate only full ADTS frames and not other data,
like id3v1 or APETags at the end of the file.

Fixes ticket #6437.

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
This commit is contained in:
James Almer 2017-06-02 20:34:24 -03:00
parent fab1863917
commit 3d40263253
1 changed files with 42 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
libavformat/aacdec.c
View File

@ -23,10 +23,11 @@
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#include "rawdec.h"
#include "id3v1.h"
#include "apetag.h"
#define ADTS_HEADER_SIZE 7
static int adts_aac_probe(AVProbeData *p)
{
int max_frames = 0, first_frames = 0;
@ -79,6 +80,7 @@ static int adts_aac_probe(AVProbeData *p)
static int adts_aac_read_header(AVFormatContext *s)
{
AVStream *st;
uint16_t state;
st = avformat_new_stream(s, NULL);
if (!st)
@ -96,18 +98,56 @@ static int adts_aac_read_header(AVFormatContext *s)
avio_seek(s->pb, cur, SEEK_SET);
}
// skip data until the first ADTS frame is found
state = avio_r8(s->pb);
while (!avio_feof(s->pb) && avio_tell(s->pb) < s->probesize) {
state = (state << 8) | avio_r8(s->pb);
if ((state >> 4) != 0xFFF)
continue;
avio_seek(s->pb, -2, SEEK_CUR);
break;
}
if ((state >> 4) != 0xFFF)
return AVERROR_INVALIDDATA;
// LCM of all possible ADTS sample rates
avpriv_set_pts_info(st, 64, 1, 28224000);
return 0;
}
static int adts_aac_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int ret, fsize;
ret = av_get_packet(s->pb, pkt, ADTS_HEADER_SIZE);
if (ret < 0)
return ret;
if (ret < ADTS_HEADER_SIZE) {
av_packet_unref(pkt);
return AVERROR(EIO);
}
if ((AV_RB16(pkt->data) >> 4) != 0xfff) {
av_packet_unref(pkt);
return AVERROR_INVALIDDATA;
}
fsize = (AV_RB32(pkt->data + 3) >> 13) & 0x1FFF;
if (fsize < ADTS_HEADER_SIZE) {
av_packet_unref(pkt);
return AVERROR_INVALIDDATA;
}
return av_append_packet(s->pb, pkt, fsize - ADTS_HEADER_SIZE);
}
AVInputFormat ff_aac_demuxer = {
.name = "aac",
.long_name = NULL_IF_CONFIG_SMALL("raw ADTS AAC (Advanced Audio Coding)"),
.read_probe = adts_aac_probe,
.read_header = adts_aac_read_header,
.read_packet = ff_raw_read_partial_packet,
.read_packet = adts_aac_read_packet,
.flags = AVFMT_GENERIC_INDEX,
.extensions = "aac",
.mime_type = "audio/aac,audio/aacp,audio/x-aac",