ptx image decoder uses get_buffer, set CODEC_CAP_DR1

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@19101 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/ptx.c

@@ -114,7 +114,7 @@ AVCodec ptx_decoder = {
     NULL,
     ptx_end,
     ptx_decode_frame,
-    0,
+    CODEC_CAP_DR1,
     NULL,
     .long_name = NULL_IF_CONFIG_SMALL("V.Flash PTX image"),
 };