h264: add avpriv_h264_has_num_reorder_frames()

This function exports the exact sps.num_reorder_frames value
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/h264.c

@@ -70,6 +70,12 @@ static const enum PixelFormat hwaccel_pixfmt_list_h264_jpeg_420[] = {
     PIX_FMT_NONE
 };
 
+int avpriv_h264_has_num_reorder_frames(AVCodecContext *avctx)
+{
+    H264Context *h = avctx->priv_data;
+    return h ? h->sps.num_reorder_frames : 0;
+}
+
 /**
  * Check if the top & left blocks are available if needed and
  * change the dc mode so it only uses the available blocks.

libavcodec/internal.h

@@ -171,4 +171,6 @@ int ff_thread_can_start_frame(AVCodecContext *avctx);
 
 int ff_get_logical_cpus(AVCodecContext *avctx);
 
+int avpriv_h264_has_num_reorder_frames(AVCodecContext *avctx);
+
 #endif /* AVCODEC_INTERNAL_H */