ImageMagick is a software suite to create, edit, and compose bitmap images. It can read, convert and write images in a variety of formats (about 100) including GIF, JPEG, JPEG-2000, PNG, PDF, PhotoCD, TIFF, and DPX.
XnConvert is an easy image converter for graphic files, photos and images available on Windows, MacOSX and Linux.
Convert and Rename images in batch mode
Support JPEG, BMP, GIF, PNG, TIFF and JPEG2000
Resize, crop, change color depth, apply color effects, add text, watermark and border effects
Rename images with sequential number
Search and replace texts in the file names
GraphicsMagick is the swiss army knife of image processing. Comprised of 282K physical lines (according to David A. Wheelers SLOCCount) of source code in the base package (or 952K including 3rd party libraries) it provides a robust and efficient collection of tools and libraries...
Image Tuner is a free software for batch resizing, converting, watermarking and renaming your digital photos and images from more than 20 image formats to JPEG, BMP, PNG, TIFF and GIF formats. The program will help you to prepare your digital photos to upload and publish them in...
Phatch is an user friendly, cross-platform Photo Batch Processor and Exif Renamer with a nice graphical user interface. Phatch handles all popular image formats and can duplicate (sub)folder hierarchies.
Last code commit in 2010, latest release from 2014.
Converseen is a free cross-platform batch image processor for Windows and Linux that allows you to convert, resize, rotate and flip an infinite number of images with a mouse click.Warning
Installation without activation key works showing different dangerous 3rd party softwares (bloatware, spyware, etc.). Avast Antivirus detected at least 3 different kind of viruses (or potentially viruses/dangerous software).
ImBatch is a batch image processor with a nice graphical user interface. It will allow you to edit multiple image files at the click of a button by using scripts. The script will be created by combining Tasks.
With BIMP you can apply a set of manipulations to an entire group of images! It provides an easy to use interface and a lot of batch functions: