Thousands of people criticized the Obama Campaign and Factcheck for failing to do the above. A digital photo is also not the same thing as a digital scan, so that argument is moot.
If Obama had a real, paper COLB as I do, then he would have made better scans. Or, at least one more scan. I've got over 60, front and back.
bottom line: Obama does not have anything that looks like what was posted.
Or his minions might have either de-noised the scanned image, or shrunk it, or reduced the color saturation, or all three, or otherwise processed it in such a way that the image would compress to a reasonably-sized jpg in order to ease web traffic. Maybe they just wanted to make it look pretty. Who knows what they were thinking?
If the image started as a decent high-resolution scan, and any of these things were done, would that in your mind constitute forgery? What if they did enough of these things to the raw scan such that the result would make it impossible for anyone to draw any conclusions at all? Where, on the scale of perfect to useless, does the quality of their published image fall? Where, on the scale of certainty to conjecture, do your conclusions fall with regard to the "scan"?