videomixer: GStreamer Good Plugins 1.0 Plugins Reference Manual

videomixer

Description

Videomixer2 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 GstVideoMixer2Pad.

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 overlayed 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 demostrate 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)

Synopsis

Element Information

plugin	videomixer
author	Wim Taymans <wim@fluendo.com>, Sebastian Dröge <sebastian.droege@collabora.co.uk>
class	Filter/Editor/Video/Compositor

Element Pads

name	sink_%u
direction	sink
presence	request
details	video/x-raw, format=(string){ AYUV, BGRA, ARGB, RGBA, ABGR, Y444, Y42B, YUY2, UYVY, YVYU, I420, YV12, NV12, NV21, Y41B, RGB, BGR, xRGB, xBGR, RGBx, BGRx }, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]

name	src
direction	source
presence	always
details	video/x-raw, format=(string){ AYUV, BGRA, ARGB, RGBA, ABGR, Y444, Y42B, YUY2, UYVY, YVYU, I420, YV12, NV12, NV21, Y41B, RGB, BGR, xRGB, xBGR, RGBx, BGRx }, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]