Add Image Type Checks

[HaleySchuhl]

Start a discussion about anything you would like We've ran into issues with the methods we use to check input image type (e.g. we look for exactly two unique values to determine an image as binary). This can cause problems when input images are incorrectly rejected or accepted as input. The suggested solution to this would be a handful of image type (and other quality control?) checks that can determine "is binary?", "is grayscale?" or otherwise. Also, could potentially handle data mismatches automatically?