From 64bde8056337bb656a11f3c9e2857c10b94e2871 Mon Sep 17 00:00:00 2001 From: "Ronald S. Bultje" Date: Wed, 2 May 2012 15:45:18 -0700 Subject: mp3/ac3 probe: search for PES headers to prevent probing MPEG-PS as MP3. --- libavformat/mp3dec.c | 30 +++++++++++++++++++++++++----- 1 file changed, 25 insertions(+), 5 deletions(-) (limited to 'libavformat/mp3dec.c') diff --git a/libavformat/mp3dec.c b/libavformat/mp3dec.c index d233209f97..39875201e3 100644 --- a/libavformat/mp3dec.c +++ b/libavformat/mp3dec.c @@ -63,11 +63,31 @@ static int mp3_read_probe(AVProbeData *p) } // keep this in sync with ac3 probe, both need to avoid // issues with MPEG-files! - if (first_frames>=4) return AVPROBE_SCORE_MAX/2+1; - else if(max_frames>500)return AVPROBE_SCORE_MAX/2; - else if(max_frames>=4) return AVPROBE_SCORE_MAX/4; - else if(max_frames>=1) return 1; - else return 0; + if (first_frames >= 4) return AVPROBE_SCORE_MAX / 2 + 1; + + if (max_frames) { + int pes = 0, i; + unsigned int code = -1; + +#define VIDEO_ID 0x000001e0 +#define AUDIO_ID 0x000001c0 + /* do a search for mpegps headers to be able to properly bias + * towards mpegps if we detect this stream as both. */ + for (i = 0; ibuf_size; i++) { + code = (code << 8) + p->buf[i]; + if ((code & 0xffffff00) == 0x100) { + if ((code & 0x1f0) == VIDEO_ID) pes++; + else if((code & 0x1e0) == AUDIO_ID) pes++; + } + } + + if (pes) + max_frames = (max_frames + pes - 1) / pes; + } + if (max_frames > 500) return AVPROBE_SCORE_MAX / 2; + else if (max_frames >= 4) return AVPROBE_SCORE_MAX / 4; + else if (max_frames >= 1) return 1; + else return 0; //mpegps_mp3_unrecognized_format.mpg has max_frames=3 } -- cgit v1.2.3