Image manipulation expert - Crop the image

Thousands of children are drawing in sheets of paper like these I'm attaching to the project. After each child make their drawings in these papers, each paper is scanned. We're looking for somebody to create a system to crop the images, so that we can have just the drawings - to convert that into a book. What should this app do: - read the QR code - each sheet has its own QR. That's how we identify the page - align the image - some images, after scanned, are bent. It may not be bent after aligning - crop just the image (like the "Cropped Drawing" file) - discard the "trash" below and beside - the gray part that eventually shows up after scanning. - we may not bleed more than 1mm of each side of the drawing after cropping - we should be warned by the system if an image is so bent that is may not be fixed (like the image 009 attached) - it should be able to process images with different dimensions (sometimes it will have 1.000 pixels, sometimes 1.500 pixels etc; and sometimes the sheet will be a little distorted), but always in the same pattern of these sheets. - this system should be able to process more than 5.000 images per day We are expecting for a clear and well commented source code. Later. Pedro