videomixer

IMPORTANT: videomixer is deprecated in favor of compositor, please do not use this element in newly-written code!

Videomixer can accept AYUV, ARGB and BGRA video streams. For each of the requested sink pads it will compare the incoming geometry and framerate to define the output parameters. Indeed output video frames will have the geometry of the biggest incoming video stream and the framerate of the fastest incoming one.

Videomixer will do colorspace conversion.

Individual parameters for each input stream can be configured on the videomixer pads.

Sample pipelines

 gst-launch-1.0 \
   videotestsrc pattern=1 ! \
   video/x-raw,format=AYUV,framerate=\(fraction\)10/1,width=100,height=100 ! \
   videobox border-alpha=0 top=-70 bottom=-70 right=-220 ! \
   videomixer name=mix sink_0::alpha=0.7 sink_1::alpha=0.5 ! \
   videoconvert ! xvimagesink \
   videotestsrc ! \
   video/x-raw,format=AYUV,framerate=\(fraction\)5/1,width=320,height=240 ! mix.

A pipeline to demonstrate videomixer used together with videobox. This should show a 320x240 pixels video test source with some transparency showing the background checker pattern. Another video test source with just the snow pattern of 100x100 pixels is overlaid on top of the first one on the left vertically centered with a small transparency showing the first video test source behind and the checker pattern under it. Note that the framerate of the output video is 10 frames per second.

 gst-launch-1.0 videotestsrc pattern=1 ! \
   video/x-raw, framerate=\(fraction\)10/1, width=100, height=100 ! \
   videomixer name=mix ! videoconvert ! ximagesink \
   videotestsrc !  \
   video/x-raw, framerate=\(fraction\)5/1, width=320, height=240 ! mix.

A pipeline to demonstrate bgra mixing. (This does not demonstrate alpha blending).

 gst-launch-1.0 videotestsrc pattern=1 ! \
   video/x-raw,format =I420, framerate=\(fraction\)10/1, width=100, height=100 ! \
   videomixer name=mix ! videoconvert ! ximagesink \
   videotestsrc ! \
   video/x-raw,format=I420, framerate=\(fraction\)5/1, width=320, height=240 ! mix.

A pipeline to test I420

 gst-launch-1.0 videomixer name=mixer sink_1::alpha=0.5 sink_1::xpos=50 sink_1::ypos=50 ! \
   videoconvert ! ximagesink \
   videotestsrc pattern=snow timestamp-offset=3000000000 ! \
   "video/x-raw,format=AYUV,width=640,height=480,framerate=(fraction)30/1" ! \
   timeoverlay ! queue2 ! mixer. \
   videotestsrc pattern=smpte ! \
   "video/x-raw,format=AYUV,width=800,height=600,framerate=(fraction)10/1" ! \
   timeoverlay ! queue2 ! mixer.

A pipeline to demonstrate synchronized mixing (the second stream starts after 3 seconds)