diff --git a/libavcodec/rawdec.c b/libavcodec/rawdec.c
index a92168e6e7..746840a31b 100644
--- a/libavcodec/rawdec.c
+++ b/libavcodec/rawdec.c
@@ -96,7 +96,7 @@ static void flip(AVCodecContext *avctx, AVPicture * picture){
 
 static int raw_decode(AVCodecContext *avctx,
                             void *data, int *data_size,
-                            uint8_t *buf, int buf_size)
+                            const uint8_t *buf, int buf_size)
 {
     RawVideoContext *context = avctx->priv_data;