CompreFace - CompreFace is a free face recognition service from Exadel that can be easily integrated into any system using simple REST API.
facedetect - facedetect is a simple face detector for batch processing.
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
Batch Image Splitter - Split multiple pictures into specified number of slices by rows and columns or into tiles of desired size. 130+ Actions and Filters: resize, watermark...
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!