Open Source C Image Converters for Apple iPhone

libjpeg-turbo is a JPEG image codec that uses SIMD instructions (MMX, SSE2, NEON, AltiVec) to accelerate baseline JPEG compression and decompression on x86, x86-64, ARM, and PowerPC systems. On such systems, libjpeg-turbo is generally 2-6x as fast as libjpeg, all else being equal. On other types of systems, libjpeg-turbo can still outperform libjpeg by a significant amount, by virtue of its highly-optimized Huffman coding routines. In many cases, the performance of libjpeg-turbo rivals that of proprietary high-speed JPEG codecs. libjpeg-turbo implements both the traditional libjpeg API as well as the less powerful but more straightforward TurboJPEG API. libjpeg-turbo also features colorspace extensions that allow it to compress from/decompress to 32-bit and big-endian pixel buffers (RGBX, XBGR, etc.), as well as a full-featured Java interface.

ImageMagick® is a free and open-source software suite for displaying, converting, and editing raster image and vector image files. It can read and write over 200 image file formats, and can support a wide range of image manipulation operations, such as resizing, cropping, and color correction. ImageMagick is written in C and is available for a wide range of operating systems, including Linux, macOS, and Windows. It can be used as a standalone application, or as a library that can be integrated into other software programs. Overall, ImageMagick is a powerful and versatile software suite for displaying, converting, and editing image files. Its support for scripting and automation, along with its other features, make it a valuable tool for a wide range of image-related tasks.