ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
Smallpdf - PDF document management and conversion suite
Ralpha Image Resizer - High-speed image batch conversion tool
iLovePDF - Free online PDF tool set
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
Kingshiper Image Compressor - With Kingshiper Image Compressor, you can easily compress, optimize and reduce jpg, jpeg, png, svg and gif file to a smaller size in seconds.