On February 25, 2020 at 22:20, Fancypants said...
You can just literally change the file or convert the file into png. Maybe you mean how to actually create a png file?
Hes asking about taking television logos and superimposing them over a button graphic to use as a favorite channel button.
.png is only important because many button graphics have edges that aren't simple/sharp so you need transparency to see the graphic behind it.
This example shows source logos on white buttons with rounded edges.