leptonica-progs

Well-tested C library for some basic image processing operations, along with a description of the functions and some design methods. A full set of affine transformations (translation, shear, rotation, scaling) on images of all depths is included, with the exception that some of the scaling methods do not work at all depths. There are also implementations of binary morphology, grayscale morphology, convolution and rank order filters, and applications such as jbig2 image processing and color quantization. You will also find basic utilities for the safe and efficient handling of arrays (of strings, numbers, number pairs and image-related geometrical objects), byte queues, generic stacks, generic lists, and endian-independent indexing into 32-bit arrays.

leptonica

* Document images * Natural images Fundamental image processing and image analysis operations * Rasterop (aka bitblt) * Affine transforms (scaling, translation, rotation, shear) on images of arbitrary pixel depth * Projective and bi-linear transforms * Binary and gray scale morphology, rank order filters, and convolution * Seed-fill and connected components * Image transformations with changes in pixel depth, both at the same scale and with scale change * Pixelwise masking, blending, enhancement, arithmetic ops, etc.