Yeah, I know. Thing is I thought that PNG compression would fail horribly at this but somehow through dark magics it compresses it to one one-thousandth of the PPM file. That's fucking insane. MAGICS I tells you.
So, necro and suchlike. Did I really sound like that? On the *internets*? Ah well. The point is to link to this: http://allrgb.com/. Very cool, does what I was trying to do, but intelligently. So I might try again, what with my increased programming knowledge over the past year (longer?).