diff --git a/libavcodec/roqvideodec.c b/libavcodec/roqvideodec.c
index c9daec729f..8949b92144 100644
--- a/libavcodec/roqvideodec.c
+++ b/libavcodec/roqvideodec.c
@@ -158,6 +158,12 @@ static av_cold int roq_decode_init(AVCodecContext *avctx)
     RoqContext *s = avctx->priv_data;
 
     s->avctx = avctx;
+
+    if (avctx->width%16 || avctx->height%16) {
+         av_log(avctx, AV_LOG_ERROR, "dimensions not being a multiple of 16 are unsupported\n");
+         return AVERROR_PATCHWELCOME;
+    }
+
     s->width = avctx->width;
     s->height = avctx->height;
     s->last_frame    = &s->frames[0];