How to make background of an animated gif transparent using PHP?

I use this library https://github.com/lunakid/AnimGif to compose a animated GIF from single frames. But when I have an alpha channel the result GIF will always have a black or another coloured background.

I tried all GIF libraries for PHP I found. Is there something I'm missing?

Thanks in advance!

Best, intxcc

Solution

You probably are using GIFs with transparent background as INPUT frames. Use PNGs (!) with a transparent background as INPUT frames and most php gif libraries should generate a GIF with transparent background.