I'm trying to do an image conversion in a rails app from SVG to PNG. ImageMagick didn't work out for me, due to Heroku not able / wanting to upgrade IM at this time. I'm testing out some ideas of using RSVG2 / Cairo in dev but running into a roadblock.
I can easily convert and save the SVG to PNG like this:
#svg_test.rb
require 'debugger'
require 'rubygems'
require 'rsvg2'
SRC = 'test.svg'
DST = 'test.png'
svg = RSVG::Handle.new_from_file(SRC)
surface = Cairo::ImageSurface.new(Cairo::FORMAT_ARGB32, 800, 800)
context = Cairo::Context.new(surface)
context.render_rsvg_handle(svg)
surface.write_to_png(DST)
But this only lets me write PNG files out. In the app, I need to be able to generate these on the fly, then send them down to the client browser as data. And I can't figure out how to do this, or even if its supported. I know I can call surface.data to get the raw data at least, but I don't know enough about image formats to know how to get this as a PNG.
Thanks