diff --git a/libavformat/format.c b/libavformat/format.c
index 7df06b70fc..d9b8989b03 100644
--- a/libavformat/format.c
+++ b/libavformat/format.c
@@ -261,8 +261,13 @@ int av_probe_input_buffer2(AVIOContext *pb, AVInputFormat **fmt,
 
     if (pb->av_class) {
         uint8_t *mime_type_opt = NULL;
+        char* semi;
         av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type_opt);
         pd.mime_type = (const char *)mime_type_opt;
+        semi = pd.mime_type?strchr(pd.mime_type, ';'):NULL;
+        if (semi) {
+            *semi='\0';
+        }
     }
 #if 0
     if (!*fmt && pb->av_class && av_opt_get(pb, "mime_type", AV_OPT_SEARCH_CHILDREN, &mime_type) >= 0 && mime_type) {