diff --git a/libavcodec/asv1.c b/libavcodec/asv1.c
index 1cb15d812d..3cfb76e65e 100644
--- a/libavcodec/asv1.c
+++ b/libavcodec/asv1.c
@@ -289,6 +289,7 @@ static inline void asv2_encode_block(ASV1Context *a, DCTELEM block[64]){
         if( (block[index + 1] = (block[index + 1]*a->q_intra_matrix[index + 1] + (1<<15))>>16) ) ccp |= 2;
         if( (block[index + 9] = (block[index + 9]*a->q_intra_matrix[index + 9] + (1<<15))>>16) ) ccp |= 1;
 
+        assert(i || ccp<8);
         if(i) put_bits(&a->pb, ac_ccp_tab[ccp][1], ac_ccp_tab[ccp][0]);
         else  put_bits(&a->pb, dc_ccp_tab[ccp][1], dc_ccp_tab[ccp][0]);