ImageMagick - ImageMagick is a software suite to create, edit, and compose bitmap images.
Sketch - Professional digital design for Mac.
OpenCV - OpenCV is the world's biggest computer vision library
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Cloudinary - Cloudinary is a cloud-based service for hosting videos and images designed specifically with the needs of web and mobile developers in mind.
Affinity Designer - Professional creative software, exclusively for Mac.