avformat/mpegts: Use differential score for analyze()

This avoids high scores in random data that has a high 0x47 frequency

Fixes Ticket3844

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2014-08-16 23:07:28 +02:00
parent b7d5e016a3
commit 427bcdf035

View File

@ -506,6 +506,7 @@ static int analyze(const uint8_t *buf, int size, int packet_size, int *index)
int stat[TS_MAX_PACKET_SIZE];
int i;
int best_score = 0;
int best_score2 = 0;
memset(stat, 0, packet_size * sizeof(*stat));
@ -517,11 +518,13 @@ static int analyze(const uint8_t *buf, int size, int packet_size, int *index)
best_score = stat[x];
if (index)
*index = x;
} else if (stat[x] > best_score2) {
best_score2 = stat[x];
}
}
}
return best_score;
return best_score - best_score2;
}
/* autodetect fec presence. Must have at least 1024 bytes */