Fix typos and missing videoconvert element to demonstrate the alphacombine element. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1494>
Fix typos and missing videoconvert element to demonstrate the alphacombine element. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1494>