mpegts: only calculate stat index when its needed during probe

40% faster probe
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/mpegts.c

@@ -452,22 +452,19 @@ static void mpegts_close_filter(MpegTSContext *ts, MpegTSFilter *filter)
 static int analyze(const uint8_t *buf, int size, int packet_size, int *index){
     int stat[TS_MAX_PACKET_SIZE];
     int i;
-    int x=0;
     int best_score=0;
 
     memset(stat, 0, packet_size*sizeof(*stat));
 
-    for(x=i=0; i<size-3; i++){
+    for(i=0; i<size-3; i++){
         if(buf[i] == 0x47 && !(buf[i+1] & 0x80) && buf[i+3] != 0x47){
+            int x = i % packet_size;
             stat[x]++;
             if(stat[x] > best_score){
                 best_score= stat[x];
                 if(index) *index= x;
             }
         }
-
-        x++;
-        if(x == packet_size) x= 0;
     }
 
     return best_score;