From f7ea6d9b64282bb11a220f3ffe8c9e94baf83221 Mon Sep 17 00:00:00 2001
From: He Junyan <junyan.he@intel.com>
Date: Fri, 6 Nov 2020 16:18:14 +0800
Subject: [PATCH] glcolorconver: Return empty caps in transform_caps if fails.

We should not return a NULL in transform_caps() function. The NULL
will generate a assert of:
  "transform_caps returned caps which are not a real subset of the
   filter caps"
in transform base class.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/922>
---
 ext/gl/gstglcolorconvertelement.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ext/gl/gstglcolorconvertelement.c b/ext/gl/gstglcolorconvertelement.c
index 256e5ef..f9f0ad7 100644
--- a/ext/gl/gstglcolorconvertelement.c
+++ b/ext/gl/gstglcolorconvertelement.c
@@ -149,7 +149,7 @@ gst_gl_color_convert_element_transform_caps (GstBaseTransform * bt,
   GstCaps *ret;
 
   if (base_filter->display && !gst_gl_base_filter_find_gl_context (base_filter))
-    return NULL;
+    return gst_caps_new_empty ();
 
   context = gst_gl_base_filter_get_gl_context (base_filter);
 
-- 
2.7.4