From 05bdd33a128dea4cea31d8b77072901f29e9ffff Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Reimar=20D=C3=B6ffinger?= Date: Mon, 14 Sep 2009 20:28:10 +0000 Subject: [PATCH] Make DTS probe more robust against false positives (as e.g. probetest shows). In particular check that the detected markers clearly indicate a specific DTS format (a wild mixture of e.g. little- and big-endian markers is unlikely to be a valid DTS file) and ensure the markers appear with sufficient frequency. Originally committed as revision 19844 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/raw.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/libavformat/raw.c b/libavformat/raw.c index d88f3ee8a3..a935ce56cd 100644 --- a/libavformat/raw.c +++ b/libavformat/raw.c @@ -510,6 +510,8 @@ static int dts_probe(AVProbeData *p) { const uint8_t *buf, *bufp; uint32_t state = -1; + int markers[3] = {0}; + int sum, max; buf = p->buf; @@ -519,18 +521,24 @@ static int dts_probe(AVProbeData *p) /* regular bitstream */ if (state == DCA_MARKER_RAW_BE || state == DCA_MARKER_RAW_LE) - return AVPROBE_SCORE_MAX/2+1; + markers[0]++; /* 14 bits big-endian bitstream */ if (state == DCA_MARKER_14B_BE) if ((bytestream_get_be16(&bufp) & 0xFFF0) == 0x07F0) - return AVPROBE_SCORE_MAX/2+1; + markers[1]++; /* 14 bits little-endian bitstream */ if (state == DCA_MARKER_14B_LE) if ((bytestream_get_be16(&bufp) & 0xF0FF) == 0xF007) - return AVPROBE_SCORE_MAX/2+1; + markers[2]++; } + sum = markers[0] + markers[1] + markers[2]; + max = markers[1] > markers[0]; + max = markers[2] > markers[max] ? 2 : max; + if (markers[max] > 3 && p->buf_size / markers[max] < 32*1024 && + markers[max] * 4 > sum * 3) + return AVPROBE_SCORE_MAX/2+1; return 0; }