compositor

Using GStreamer framework compositor element for merging many video displays into single view

The GStreamer framework compositor element allows to merge multiple displays into one.

Add compositor element along with its name e.g. name=comp and the sink pad x,y coordinates position e.g. sink_0::xpos=0 sink_0::ypos=0 to GStreamer framework pipeline. Each output display requires a separate sink pad definition. The last component is autovideosink sync=false.

compositor name=comp sink_0::xpos=0 sink_0::ypos=0 sink_1::xpos=720 sink_1::ypos=0 ... ! autovideosink sync=false

The below example presents usage of the GStreamer framework compositor element for merging 4 output videos into a single display.

gst-launch-1.0 compositor name=comp sink_0::xpos=0 sink_0::ypos=0 sink_1::xpos=720 sink_1::ypos=0 sink_2::xpos=0 sink_2::ypos=400 sink_3::xpos=720 sink_3::ypos=400 ! autovideosink sync=false \
filesrc location=${VIDEO_FILE_1} ! parsebin ! vah264dec ! "video/x-raw(memory:VAMemory)" ! \
gvadetect model=${MODEL_FILE} device=GPU pre-process-backend=va model-instance-id=inf0 batch-size=4 ! queue ! gvawatermark ! videoconvert ! gvafpscounter ! comp.sink_0  \
filesrc location=${VIDEO_FILE_2} ! parsebin ! vah264dec ! "video/x-raw(memory:VAMemory)" ! \
gvadetect model=${MODEL_FILE} device=GPU pre-process-backend=va model-instance-id=inf0 batch-size=4 ! queue ! gvawatermark ! videoconvert ! gvafpscounter ! comp.sink_1 \
filesrc location=${VIDEO_FILE_3} ! parsebin ! vah264dec ! "video/x-raw(memory:VAMemory)" ! \
gvadetect model=${MODEL_FILE} device=GPU pre-process-backend=va model-instance-id=inf0 batch-size=4 ! queue ! gvawatermark ! videoconvert ! gvafpscounter ! comp.sink_2 \
filesrc location=${VIDEO_FILE_4} ! parsebin ! vah264dec ! "video/x-raw(memory:VAMemory)" ! \
gvadetect model=${MODEL_FILE} device=GPU pre-process-backend=va model-instance-id=inf0 batch-size=4 ! queue ! gvawatermark ! videoconvert ! gvafpscounter ! comp.sink_3