diff --git a/libavformat/mpegvideodec.c b/libavformat/mpegvideodec.c
index 1b057bdf990c82c3a0fd872a17957e558e13f274..1b724bc2b97001e88bfa523917ca8e35df82bd52 100644
--- a/libavformat/mpegvideodec.c
+++ b/libavformat/mpegvideodec.c
@@ -43,9 +43,9 @@ static int mpegvideo_probe(AVProbeData *p)
             switch(code){
             case     SEQ_START_CODE:   seq++; break;
             case PICTURE_START_CODE:   pic++; break;
-            case   SLICE_START_CODE...0x1af: slice++; break;
             case    PACK_START_CODE: pspack++; break;
             }
+            if (code >= SLICE_START_CODE && code <= 0x1af) slice++;
             if     ((code & 0x1f0) == VIDEO_ID)   vpes++;
             else if((code & 0x1e0) == AUDIO_ID)   apes++;
         }