libVLC alpha channel support

[dm-helper]

Hi,

I'm looking to play videos overlayed on top of one another or on top of other content in the background. The sample webm videos I am using (e.g. here: https://simpl.info/videoalpha/) definitely include an alpha channel which is played correctly in various browsers, but seems not to be processed by libvlc. I have been using v3.0.8, but also tested this using a recent 4.x nightly. I've tried RV32 or RGBA and confirmed that if I manually edit the pixel data to set the alpha component, the rest of my graphics pipeline blends the images properly.

I found this post from the beginning of the year: https://forum.videolan.org/viewtopic.ph ... el#p485306
Unfortunately, I haven't been able to find a bug, which was suggested by Jean-Baptiste at the bottom and haven't had any success myself so far.

Is this functionality something that I can realistically expect to be improved in the near future? That would be helpful for me to know to be able to prioritize my own backlog. I would even be willing to look into it myself, although my knowledge of the libvlc architecture is so limited that I'm not sure that would be wise for anybody.

Thanks in advance!

[mfkl]

Have you tried

Code: Select all

Alpha mask video filter (alphamask) Use an image's alpha channel as a transparency mask. --alphamask-mask=<string> Transparency mask Alpha blending transparency mask. Uses a png alpha channel.