diff --git a/libavcodec/svq1dec.c b/libavcodec/svq1dec.c
index 187522c3bf..573568374a 100644
--- a/libavcodec/svq1dec.c
+++ b/libavcodec/svq1dec.c
@@ -692,7 +692,7 @@ static int svq1_decode_frame(AVCodecContext *avctx, void *data,
         } else {
             /* delta frame */
             uint8_t *previous = s->prev->data[i];
-            if (!previous) {
+            if (!previous || s->prev->width != s->cur->width || s->prev->height != s->cur->height) {
                 av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n");
                 result = AVERROR_INVALIDDATA;
                 goto err;