Post img to friend's wallpaper using facebook api

[rafirm12]

I'm using a html5 canvas on my site to paint a image.Objective, now: [*]create a album "paints"+"date" and insert the converted png per onclick-event[*]possibility to select a friend of mine in fb[*]post the png for to the wall of my friend[*]do i have to save the png on my server first?Is there any smart way to this using fb-api?Actually, i use the fb javascript sdk.Thank you so much for your help!Regards Martin