I have made the same topic months ago, but left the project and now trying to redo it again.
Problem: I have a panel with a BackgroundImage. I want to make a color (lets say white) transparent, thus that color not to be painted at all.
I googled I tried and failed. The only thing that seemed to work is when you use the Graphics.DrawImage() method and use the ColorMatrix and ImageAttribute classes to give some transparency on the image. But you cannot choose a specific color to make transparent, you can only work on the RGBA channels, which isn't helpful in my situation.
So what can I do here?