How do I save WriteableBitmap as png image with transparency

Question

I crop the circular area from the image for the avatar. I need to get pixels byte[] of the image and upload to the server in base64 format. Unfortunately method SaveJpeg() does not support transparency pixels outside the selected circle. I tried ImageTools library, but no other platform except WindowsPhone unable to create png image from the resulting byte[]. Is there a way to do this?

Answer 1

There is no platform API to do this. The ToolStack PNG library presents a lightweight solution.

http://toolstack.com/libraries/pngwriter