PHP Graphics Magick

High-performance Node.js image processing module built on the libvips library for fast transformations

Open-source smart imaging service which allows on-demand cropping, resizing and flipping of images

The industry-standard open-source software suite for creating, editing, and converting bitmap images

Fast and secure standalone server for resizing and converting remote images on-the-fly

Extremely fast, low-memory image processing library with bindings for many languages

Open-source JPEG encoder that improves compression while maintaining full compatibility