@@ -27,6 +27,9 @@

 #define ALT_BITSTREAM_READER_LE

 #include "get_bits.h"

+#define BINK_FLAG_ALPHA 0x00100000

+#define BINK_FLAG_GRAY  0x00020000

+

 static VLC bink_trees[16];

 /**

@@ -930,13 +933,19 @@ static av_cold int decode_init(AVCodecContext *avctx)

     BinkContext * const c = avctx->priv_data;

     static VLC_TYPE table[16 * 128][2];

     int i;

+    int flags;

     c->version = avctx->codec_tag >> 24;

     if (c->version < 'c') {

         av_log(avctx, AV_LOG_ERROR, "Too old version '%c'\n", c->version);

         return -1;

     }

-    c->has_alpha = 0; //TODO: demuxer should supply decoder with flags

+    if (avctx->extradata_size < 4) {

+        av_log(avctx, AV_LOG_ERROR, "Extradata missing or too short\n");

+        return -1;

+    }

+    flags = AV_RL32(avctx->extradata);

+    c->has_alpha = flags & BINK_FLAG_ALPHA;

     c->swap_planes = c->version >= 'i';

     if (!bink_trees[15].table) {

         for (i = 0; i < 16; i++) {