generic-library/ffmpeg
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

allow ffmpeg to read mp3s beginning with partial frames

Browse Source 
Patch by Andreas Oman andreas A olebyn P nu
Original thread:
Date: Sep 10, 2006 7:26 AM
Subject: Re: [Ffmpeg-devel] [PATCH] allow ffmpeg to read mp3s beginning with partial frames

Originally committed as revision 6225 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Andreas Öman 2006-09-10 20:31:58 +00:00 committed by Guillaume Poirier
parent 73a8ceaa17
commit abade1429e
1 changed files with 26 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
libavformat/mp3.c
View File

@ -17,6 +17,7 @@
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include "mpegaudio.h"
#define ID3_HEADER_SIZE 10
#define ID3_TAG_SIZE 128
@ -243,27 +244,38 @@ static void id3_create_tag(AVFormatContext *s, uint8_t *buf)
static int mp3_read_probe(AVProbeData *p)
{
int d;
int max_frames;
int fsize, frames;
uint32_t header;
uint8_t *buf, *buf2, *end;
AVCodecContext avctx;
if(p->buf_size < 4)
if(p->buf_size < ID3_HEADER_SIZE)
return 0;
if(p->buf[0] == 'I' && p->buf[1] == 'D' && p->buf[2] == '3' &&
p->buf[3] < 5)
if(id3_match(p->buf))
return AVPROBE_SCORE_MAX;
if(p->buf[0] != 0xff)
return 0;
max_frames = 0;
buf = p->buf;
end = buf + FFMIN(4096, p->buf_size - sizeof(uint32_t));
d = p->buf[1];
if((d & 0xe0) != 0xe0 || ((d & 0x18) == 0x08 || (d & 0x06) == 0))
return 0;
for(; buf < end; buf++) {
buf2 = buf;
d = p->buf[2];
if((d & 0xf0) == 0xf0 || (d & 0x0c) == 0x0c)
return 0;
return AVPROBE_SCORE_MAX;
for(frames = 0; buf < end; frames++) {
header = (buf2[0] << 24) | (buf2[1] << 16) | (buf2[2] << 8) | buf2[3];
fsize = mpa_decode_header(&avctx, header);
if(fsize < 0)
break;
buf2 += fsize;
}
max_frames = FFMAX(max_frames, frames);
}
if (max_frames>=3) return AVPROBE_SCORE_MAX/2+1;
else if(max_frames==2) return AVPROBE_SCORE_MAX/4;
else if(max_frames==1) return 1;
else return 0;
}
static int mp3_read_header(AVFormatContext *s,