From f6765f3f04518bd0c2172733139422be49c1c82c Mon Sep 17 00:00:00 2001 From: Reimar Döffinger Date: Tue, 29 Sep 2009 10:12:18 +0000 Subject: Extend DV autodetection to also reliably detect single-frame DVs with a higher score that MAX/4. It checks that there are at least 10 DIF headers and at least one per 24000 bytes, and if so considers the file reliably detected as DV. Passes probetest, too. Originally committed as revision 20074 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/dv.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'libavformat/dv.c') diff --git a/libavformat/dv.c b/libavformat/dv.c index 1623953440..8e0a83492e 100644 --- a/libavformat/dv.c +++ b/libavformat/dv.c @@ -489,6 +489,7 @@ static int dv_probe(AVProbeData *p) unsigned state, marker_pos = 0; int i; int matches = 0; + int secondary_matches = 0; if (p->buf_size < 5) return 0; @@ -497,6 +498,10 @@ static int dv_probe(AVProbeData *p) for (i = 4; i < p->buf_size; i++) { if ((state & 0xffffff7f) == 0x1f07003f) matches++; + // any section header, also with seq/chan num != 0, + // should appear around every 12000 bytes, at least 10 per frame + if ((state & 0xff07ff7f) == 0x1f07003f) + secondary_matches++; if (state == 0x003f0700 || state == 0xff3f0700) marker_pos = i; if (state == 0xff3f0701 && i - marker_pos == 80) @@ -505,7 +510,7 @@ static int dv_probe(AVProbeData *p) } if (matches && p->buf_size / matches < 1024*1024) { - if (matches > 4) + if (matches > 4 || (secondary_matches >= 10 && p->buf_size / secondary_matches < 24000)) return AVPROBE_SCORE_MAX*3/4; // not max to avoid dv in mov to match return AVPROBE_SCORE_MAX/4; } -- cgit v1.2.3