omadec: loosen format probing constraints

Imporoves detection of some files in the wild:

- ID3v2 a.k.a. "ea3" header is optional.
- Version and flags in ID3v2 header are unspecified.

Signed-off-by: David Goldwich <david.goldwich@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
This commit is contained in:
David Goldwich 2013-10-24 15:24:26 +02:00 committed by Anton Khirnov
parent 1c736bedd9
commit 0a7fef39fc
1 changed files with 4 additions and 11 deletions

View File

@ -446,23 +446,16 @@ static int oma_read_packet(AVFormatContext *s, AVPacket *pkt)
static int oma_read_probe(AVProbeData *p)
{
const uint8_t *buf;
const uint8_t *buf = p->buf;
unsigned tag_len = 0;
buf = p->buf;
if (p->buf_size < ID3v2_HEADER_SIZE ||
!ff_id3v2_match(buf, ID3v2_EA3_MAGIC) ||
buf[3] != 3 || // version must be 3
buf[4]) // flags byte zero
return 0;
tag_len = ff_id3v2_tag_len(buf);
if (p->buf_size >= ID3v2_HEADER_SIZE && ff_id3v2_match(buf, ID3v2_EA3_MAGIC))
tag_len = ff_id3v2_tag_len(buf);
/* This check cannot overflow as tag_len has at most 28 bits */
if (p->buf_size < tag_len + 5)
/* EA3 header comes late, might be outside of the probe buffer */
return AVPROBE_SCORE_EXTENSION;
return tag_len ? AVPROBE_SCORE_EXTENSION : 0;
buf += tag_len;