diff --git a/libavcodec/jpeg2000dec.c b/libavcodec/jpeg2000dec.c
index 1a8ba3877b..de9aa6dbc6 100644
--- a/libavcodec/jpeg2000dec.c
+++ b/libavcodec/jpeg2000dec.c
@@ -1392,6 +1392,11 @@ static int decode_cblk(Jpeg2000DecoderContext *s, Jpeg2000CodingStyle *codsty,
         }
         pass_cnt ++;
     }
+
+    if (cblk->data + cblk->length != t1->mqc.bp) {
+        av_log(s->avctx, AV_LOG_WARNING, "End mismatch %"PTRDIFF_SPECIFIER"\n", cblk->data + cblk->length - t1->mqc.bp);
+    }
+
     return 0;
 }