From 93d3e278cd095f4a9d44513b91ce0785b2b159a2 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 2 Feb 2006 13:56:42 +0000 Subject: [PATCH] improve mpeg1/2-es detection Originally committed as revision 4923 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavformat/raw.c | 37 +++++++++++++++++-------------------- 1 file changed, 17 insertions(+), 20 deletions(-) diff --git a/libavformat/raw.c b/libavformat/raw.c index 6016c32058..c29e5f3af6 100644 --- a/libavformat/raw.c +++ b/libavformat/raw.c @@ -286,31 +286,28 @@ static int video_read_header(AVFormatContext *s, #define SEQ_START_CODE 0x000001b3 #define GOP_START_CODE 0x000001b8 #define PICTURE_START_CODE 0x00000100 +#define SLICE_START_CODE 0x00000101 +#define PACK_START_CODE 0x000001ba -/* XXX: improve that by looking at several start codes */ static int mpegvideo_probe(AVProbeData *p) { - int code; - const uint8_t *d; + uint32_t code= -1; + int pic=0, seq=0, slice=0, pspack=0; + int i; - /* we search the first start code. If it is a sequence, gop or - picture start code then we decide it is an mpeg video - stream. We do not send highest value to give a chance to mpegts */ - /* NOTE: the search range was restricted to avoid too many false - detections */ - - if (p->buf_size < 6) - return 0; - d = p->buf; - code = (d[0] << 24) | (d[1] << 16) | (d[2] << 8) | (d[3]); - if ((code & 0xffffff00) == 0x100) { - if (code == SEQ_START_CODE || - code == GOP_START_CODE || - code == PICTURE_START_CODE) - return 50 - 1; - else - return 0; + for(i=0; ibuf_size; i++){ + code = (code<<8) + p->buf[i]; + if ((code & 0xffffff00) == 0x100) { + switch(code){ + case SEQ_START_CODE: seq++; break; + case PICTURE_START_CODE: pic++; break; + case SLICE_START_CODE: slice++; break; + case PACK_START_CODE: pspack++; break; + } + } } + if(seq && pic && slice && seq