I've been trying to clean up this scan of an obscure book of sheet music for a while now, and it's been driving me nuts.
The initial scan was made (somewhat hastily) with one of those overhead book-cameras. The main problems are that some of the images are lightly distorted due to the curve of the page, and the colors aren't right - every page is black-on-grey.
I've Googled around and found ScanTailor Advanced, but from the looks of things, while it can fix the distortion, it has to be manually, laboriously applied to each individual page. I guess I can just live with it.
The colors are what frustrate me. Messing about with Irfanview, I've tried to find combinations of successively adjusting the colors and shifting the contrast to bring back the original look of the page, and while I've had some success, some of the pages are just a little darker than others and still turn out looking grey while other pages look okay. Things are complicated by the fact that some pages have greyscale images that I also want to preserve.
Is there some obvious solution I'm overlooking here? It feels like this is a simple problem that someone, somewhere would have solved by now, but I can't seem to find the answer.