From 462800e9c632fe28bcce2d5523e3b05090052057 Mon Sep 17 00:00:00 2001
From: Nicolas Dufresne <nicolas.dufresne@collabora.com>
Date: Tue, 7 Jun 2016 16:42:09 -0400
Subject: [PATCH] v4l2videodec: Keep part of the input buffer

Instead of completely getting rid of the input buffer, copy
the metadata, the flags and the timestamp into an empty buffer.
This way the decoder base class can copy that information again
to the output buffer.

https://bugzilla.gnome.org/show_bug.cgi?id=758424
---
 sys/v4l2/gstv4l2videodec.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/sys/v4l2/gstv4l2videodec.c b/sys/v4l2/gstv4l2videodec.c
index 0a2eace32f..d148b66ad5 100644
--- a/sys/v4l2/gstv4l2videodec.c
+++ b/sys/v4l2/gstv4l2videodec.c
@@ -522,6 +522,8 @@ gst_v4l2_video_dec_handle_frame (GstVideoDecoder * decoder,
   GstV4l2Error error = GST_V4L2_ERROR_INIT;
   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
   GstFlowReturn ret = GST_FLOW_OK;
+  gboolean processed = FALSE;
+  GstBuffer *tmp;
 
   GST_DEBUG_OBJECT (self, "Handling frame %d", frame->system_frame_number);
 
@@ -555,8 +557,8 @@ gst_v4l2_video_dec_handle_frame (GstVideoDecoder * decoder,
     if (codec_data) {
       gst_buffer_ref (codec_data);
     } else {
-      codec_data = frame->input_buffer;
-      frame->input_buffer = NULL;
+      codec_data = gst_buffer_ref (frame->input_buffer);
+      processed = TRUE;
     }
 
     /* Ensure input internal pool is active */
@@ -666,7 +668,7 @@ gst_v4l2_video_dec_handle_frame (GstVideoDecoder * decoder,
       goto start_task_failed;
   }
 
-  if (frame->input_buffer) {
+  if (!processed) {
     GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
     ret =
         gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->v4l2output->
@@ -680,11 +682,16 @@ gst_v4l2_video_dec_handle_frame (GstVideoDecoder * decoder,
     } else if (ret != GST_FLOW_OK) {
       goto process_failed;
     }
-
-    /* No need to keep input arround */
-    gst_buffer_replace (&frame->input_buffer, NULL);
   }
 
+  /* No need to keep input arround */
+  tmp = frame->input_buffer;
+  frame->input_buffer = gst_buffer_new ();
+  gst_buffer_copy_into (frame->input_buffer, tmp,
+      GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS |
+      GST_BUFFER_COPY_META, 0, 0);
+  gst_buffer_unref (tmp);
+
   gst_video_codec_frame_unref (frame);
   return ret;