dmMediaConverter - FFmpeg GUI
Ralpha Image Resizer - High-speed image batch conversion tool
AppleMacSoft DRM Video Converter - Convert iTunes M4V to MP4 on Mac
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
321Soft Video Converter for Mac - 321Soft Mac Video Converter allows you to easily download, convert and edit video, HD video, 4K video, audio on Mac OS X.
Caesium Image Compressor - Compress your pictures up to 90% without visible quality loss.