From Ingo Schmoekel:
ImageCategorizer - the very special search-app for your images. A gui-application for all 32- and 64-bit-windows-systems. Searching directly or in batch mode. Insert it with a mouseklick into the explorer context menu. Searching for images with special formats or special colour distributions or bw/grey/coloured or pixel dimensions or imagetypes or aspect ratios or ImageCategorizer comes along with an easy install-/uninstall-set and a user guide and it's easy to use. ImageCategorizer - to keep control.