1. A computer-implemented method for restoring appearances of scans of damaged physical documents, the computer-implemented method comprising: receiving a scanned image of a physical document that includes ink writing; determining an ink bleed model by analyzing colors of pixels in the scanned image of the physical document, the ink bleed model comprising a gradient of colors from ink colors having bleed at different rates on the physical document; and restoring an appearance of the scanned image of the physical document by changing colors of pixels of the scanned image of the physical document to reduce ink bleed based on the ink bleed model.