diff --git a/libavcodec/ffv1.c b/libavcodec/ffv1.c
index 6d036685b9..540dfdb51f 100644
--- a/libavcodec/ffv1.c
+++ b/libavcodec/ffv1.c
@@ -1100,7 +1100,7 @@ static av_cold int encode_init(AVCodecContext *avctx)
                     goto slices_ok;
             }
         }
-        av_log(avctx, AV_LOG_ERROR, "Unsupported number %d of slices requested, please specify a supported number with -slices\n", avctx->slices);
+        av_log(avctx, AV_LOG_ERROR, "Unsupported number %d of slices requested, please specify a supported number with -slices (ex:4,6,9,12,16, ...)\n", avctx->slices);
         return -1;
         slices_ok:
         write_extra_header(s);