Hi,all.
Since it was recommended to make another question from the following questions, I made another question.
https://community.nxp.com/t5/i-MX-Processors/Gstreamer-i-MX8MMini-pipeline/m-p/1650686#M205902
I am developing an application that controls the screen display on a board that uses the i.MX8MMini.
What I'm trying to do now is display a video with coordinates and dimensions on top of weston's default screen. I expect weston's default screen to be transparent, except for the video playback area.
Display a transparent image (R, G, B = 0, 0, 0) called invisible.png at 1920x1080, display (x, y) = (640, 0) to 1280x952 videotestsrc on it, and display (R, G,B=0,0,0) can be set as a transparent color, so I built the following pipeline.
gst-launch-1.0 imxcompositor_g2d name=comp \
sink_0::xpos=0 sink_0::ypos=0 sink_0::width=1920 sink_0::height=1080 \
sink_1::xpos=640 sink_1::ypos=0 sink_1::width=1280 sink_1::height=952 ! \
video/x-raw,format=RGB16 ! waylandsink window-width=1920 window-height=1080 \
filesrc location=invisible.png ! pngdec ! alpha method=custom target-r=0 target-b=0 target-g=0 ! imagefreeze ! video/x-raw,width=1920,height=1080,framerate=10/1 ! comp.sink_0 \
videotestsrc ! video/x-raw,width=1280,height=952 ! comp.sink_1
However, I was expecting the default image displayed by weston to be transparent, like the attached image, but it is not transparent and shows a black screen.
Is there anything we can do from here?
could you explain these pics stand for?
Sorry, my explanation was lacking.
"gstreamer_test.png" is an image diagram of what you want to display.
"RIMG7765.JPG" is weston's default screen actually shown on the display.
"invisible.png" is the 1980x1080 transparent image you are displaying in the pipeline.
it seems this is exist bug
https://gstreamer-devel.narkive.com/Tp62Zghb/gstreamer-alpha-channel-on-black