nvivafilter may work as alpha plugin works, but nvcompositor would not be able to process it.
Attached a nvivafilter:
nviva-alpha-test.tgz (4.4 KB)
just doing thresholding from hue to alpha.
tar zxvf nviva-alpha-test.tgz
cd alpha-test
# You would edit Makefile and tune for your case (opencv install path...)
make
# in my case I used opencv-4.6.0 installed into /usr/local/opencv-4.6.0, so I first added (this may not be required for your case if you have a standard opencv intall, just for reference):
export LD_LIBRARY_PATH=/usr/local/cuda-11.4/lib64:/usr/local/opencv-4.6.0/lib:
It works with compositor:
gst-launch-1.0 videotestsrc pattern=snow ! video/x-raw,width=1280,height=720,framerate=30/1 ! queue ! comp.sink_0 videotestsrc ! video/x-raw,width=640,height=480,framerate=30/1 ! nvvidconv ! 'video/x-raw(memory:NVMM)' ! nvivafilter cuda-process=1 customer-lib-name=./lib-gst-custom-opencv_cudaprocess.so ! 'video/x-raw(memory:NVMM),format=RGBA' ! nvvidconv ! queue ! comp.sink_1 compositor name=comp sink_0::xpos=0 sink_0::ypos=0 sink_0::zorder=1 sink_1::xpos=0 sink_1::ypos=0 sink_1::zorder=2 ! videoconvert ! xvimagesink
but doesn’t work with nvcompositor:
gst-launch-1.0 videotestsrc pattern=snow ! video/x-raw,width=1280,height=720,framerate=30/1 ! nvvidconv ! 'video/x-raw(memory:NVMM),format=RGBA' ! queue ! comp.sink_0 videotestsrc ! video/x-raw,width=640,height=480,framerate=30/1 ! nvvidconv ! 'video/x-raw(memory:NVMM)' ! nvivafilter cuda-process=1 customer-lib-name=./lib-gst-custom-opencv_cudaprocess.so ! 'video/x-raw(memory:NVMM),format=RGBA' ! nvvidconv ! 'video/x-raw(memory:NVMM),format=RGBA' ! queue ! comp.sink_1 nvcompositor name=comp sink_0::xpos=0 sink_0::ypos=0 sink_0::zorder=1 sink_1::xpos=0 sink_1::ypos=0 sink_1::zorder=2 ! nvvidconv ! xvimagesink
