See also:

FreeImage - Open Source library project for developers who would like to support popular graphics image formats like PNG, BMP, JPEG, TIFF.
Imebra - C++ multiplatform GPL library for handling DICOM files (medical images) and JPEG files.
libwmf - A library to convert microsoft WMF file format to something useful, currently bindings exist to convert them to onscreen X graphics, to the GIF and to FIG.
MNG - Is the animation extension to the popular PNG image-format. It brings the ease of GIF animations, WITHOUT the patent licensing issues. Libmng is the MNG library (free software by Gerard Juyn).
paintlib - Portable library of image file decoders. Supports PNG, TGA, TIFF, JPEG/JFIF, BMP, and Mac PICT formats. Full C++ source provided.
Victor Image Processing Library - Image toolkit for DOS, Win16, and Win32 supporting TIFF, LZW, PackBits, GIF, JPEG, lossy, PCX, PNG, TGA, Targa, BMP, DIB, BIF, raw data, bitmap, TWAIN, scanning, image processing, and printing. (Source code is available, but this is a commercial library.)

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