diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 9f630fed69e563621b23598c22a1542c3ec69b43..a9f3164dee260c5cde0ad6624446509e16dbf362 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -266,11 +266,14 @@ enum PixelFormat {
 };
 
 /* currently unused, may be used if 24/32 bits samples ever supported */
+/* all in native endian */
 enum SampleFormat {
-    SAMPLE_FMT_S16 = 0,         ///< signed 16 bits
+    SAMPLT_FMT_NONE = -1,
+    SAMPLE_FMT_U8,              ///< unsigned 8 bits
+    SAMPLE_FMT_S16,             ///< signed 16 bits
+    SAMPLE_FMT_S24,             ///< signed 24 bits
     SAMPLE_FMT_S32,             ///< signed 32 bits
     SAMPLE_FMT_FLT,             ///< float
-    SAMPLE_FMT_DBL,             ///< double
 };
 
 /* in bytes */
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index 04d5081c7d306ca25fe81fc08e2fdc0ea35bbcab..235c0676d7806eb6bc04f47d59199bc824a2fdf7 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -788,6 +788,7 @@ void avcodec_get_context_defaults(AVCodecContext *s){
     s->pix_fmt= PIX_FMT_NONE;
     s->frame_skip_cmp= FF_CMP_DCTMAX;
     s->nsse_weight= 8;
+    s->sample_fmt= SAMPLE_FMT_S16; // FIXME: set to NONE
 
     s->intra_quant_bias= FF_DEFAULT_QUANT_BIAS;
     s->inter_quant_bias= FF_DEFAULT_QUANT_BIAS;