BRL-CAD is a powerful constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing support for rendering and geometric analysis, path-tracing for realistic image synthesis, network distributed framebuffer support, and image and signal-processing tools.
FreeImage is an Open Source library project for developers who would like to support popular graphics image formats in their software. The libraries are available in both binary and source distributions. FreeImage supports BMP, CUT, ICO, IFF, JBIG, JNG, JPEG, JFIF, KOALA, LBM, PCD, PBM, PGM, PNG, PPM, PSD, RAS, TARGA, TIFF, and WBMP.
The Geospatial Data Abstraction Library (GDAL) is a unifying C/C++ API for accessing raster geospatial data, and currently includes formats like GeoTIFF, Erdas Imagine, Arc/Info Binary, CEOS, DTED, GXF, and SDTS. It is intended to provide efficient access, suitable for use in viewer applications, and also attempts to preserve coordinate systems and metadata. Python, C, and C++ interfaces are available.
GraphicsMagick is a robust collection of tools and libraries which support reading, writing, and manipulating an image in over 90 major formats including popular formats like DPX, DICOM, BMP, GIF, JPEG, JPEG-2000, PDF, PNG, PNM, SVG, and TIFF. A high-quality 2D renderer is included, which provides a subset of SVG capabilities. C, C++, Perl, Tcl, and Ruby are supported. Originally based on ImageMagick, GraphicsMagick focuses on performance, minimizing bugs, and providing stable APIs and ABIs. It runs on all modern variants of Unix, Windows, and Mac OS X.
Noptec Vector is an implementation of a bitmap vectorizing algorithm, specifically for creating background picture resources for the Sierra AGI interpreter. The program reads an image in BMP, PCX, or TGA format, converts it to 160 x 168 x 16 colors and writes the result in AGI readable format, optionally showing the result onscreen.
PLIB is a set of libraries to write games and other realtime interactive applications that are 100% portable across a wide range of hardware and operating systems. It's used by Majik3D, FlightGear, and others, and includes libraries for GUI widgets, sound replay, geometry, scene graph, joystick, and fonts/text.