javascript - Convert Canvas DataURL to image for posting to Facebook -

i have canvas saving dataurl, , right click , save image files, how convert image either on client-side or server-side(rails) purpose of posting facebook (with koala gem)

if try putting dataurl straight facebook, error:

invalid arguments initialize uploadableio 

i getting dataurl server-side doing this:

  stage.todataurl({ callback: function(dataurl) {     $("#hidden").html('<input id="image" name="image" type="hidden" value="' + dataurl + '">') } }); 

anyway, seems facebook's api not accept dataurl, how go making image file , sending off?

what you've done seems opposite of this:

https://stackoverflow.com/a/4776378/637283

so perhaps using technique turn dataurl image() first work?

i haven't tried let know how goes.