XnConvert - XnConvert is an easy image converter for graphic files, photos and images available on Windows...
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
BatchPhoto - BatchPhoto is a batch photo editing software for Win and Mac that can convert, resize, annotate and watermark hundreds of photos in one go. Learn more and try it for Free!
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
GraphicConverter - Graphic Converter for Mac and Windows, can converts image formats BMP, JPG, GIF, ICO, PNG, TIF...
Phatch - Phatch = Photo & Batch!