From e1f3214c6ce91d3c34366d30636d4df74a4fe4c7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebastian=20Dr=C3=B6ge?= <sebastian@centricular.com>
Date: Tue, 13 Jan 2015 14:54:26 +0100
Subject: [PATCH] compositor: Don't do any conversions if the pad is completely
 transparent anyway

---
 gst/compositor/compositor.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/gst/compositor/compositor.c b/gst/compositor/compositor.c
index ba08556590..d3fa3f07b8 100644
--- a/gst/compositor/compositor.c
+++ b/gst/compositor/compositor.c
@@ -390,7 +390,12 @@ gst_compositor_pad_prepare_frame (GstVideoAggregatorPad * pad,
     g_free (wanted_colorimetry);
   }
 
-  if (cpad->convert) {
+  if (cpad->alpha == 0.0) {
+    GST_DEBUG_OBJECT (vagg, "Pad has alpha 0.0, not converting frame");
+    converted_frame = NULL;
+    gst_video_frame_unmap (frame);
+    g_slice_free (GstVideoFrame, frame);
+  } else if (cpad->convert) {
     gint converted_size;
 
     converted_frame = g_slice_new0 (GstVideoFrame);