Many mp3s seem to contain padding after id3 tags that is not considered in the

tag size. Skip this to make the format probing quicker.

Originally committed as revision 22111 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/mp3.c

@@ -45,10 +45,12 @@ static int mp3_read_probe(AVProbeData *p)
     if(ff_id3v2_match(buf0)) {
         buf0 += ff_id3v2_tag_len(buf0);
     }
+    end = p->buf + p->buf_size - sizeof(uint32_t);
+    while(buf0 < end && !*buf0)
+        buf0++;
 
     max_frames = 0;
     buf = buf0;
-    end = p->buf + p->buf_size - sizeof(uint32_t);
 
     for(; buf < end; buf= buf2+1) {
         buf2 = buf;