glvideomixer leaks memory when feeding into a capsfilter, or when feeding into a non-gl based sink. Pipeline eats up most of system memory eventually (as reported by e.g. vmstat / free).

gst-launch-1.0 uridecodebin  uri=file:///opt/Videos/test.avi ! glvideomixer ! video/x-raw, width=1280, height=720 ! glimagesink

GST_DEBUG=4 log: http://pastebin.com/yy2yTT1Q
valgrind:  http://pastebin.com/Cyg6DU1y


or: 
gst-launch-1.0 uridecodebin  uri=file:///opt/Videos/test.avi ! glvideomixer ! video/x-raw, width=1280, height=720 ! autovideosink
where autovideosink defaults to xvimagesink on this platform (i.e. not glimagesink).

GST_DEBUG=4 log: http://pastebin.com/mUKMXxXk
valgrind: http://pastebin.com/cxXkcQnW


Leak also happens without a caps element, as long as glvideomixer feeds into non-gl sink (autovideosink): 

gst-launch-1.0 uridecodebin  uri=file:///opt/Videos/test.avi !  glvideomixer   ! autovideosink

GST_DEBUG=4 log: http://pastebin.com/kP1irDRt
in this case memory usage increases at a slower rate than previous pipelines, but is still visible.

Pipeline "gst-launch-1.0 uridecodebin  uri=file:///opt/Videos/test.avi ! glvideomixer ! glimagesink" does not appear to leak memory. Identical pipelines with compositor instead of glviodemixer element also do not leak.

There are a lot of the following debug messages in the leaking cases:
"glmixer gstglmixer.c:1148:gst_gl_mixer_process_textures: Output Buffer does not contain correct memory, attempting to wrap for download"
Perhaps the leaks and extra memory allocations happen only when downloading / uploading some pbo or other object due to inappropriate memory type?


Tested with master repos from 22/2/2015