pHash is an implementation of various perceptual hashing algorithms. A perceptual hash is a fingerprint of a multimedia file derived from various features from its content. Unlike cryptographic hash functions that rely on the avalanche effect of small changes in input leading to drastic changes in the output, perceptual hashes are "close" to one another if the features are similar. Potential applications include copyright protection, similarity searches for media files, or even digital forensics.
FidoCadJ is a very easy-to-use editor, with a library of electrical symbols and footprints (through hole and SMD). Drawings can be exported in several graphic formats (PDF, EPS, PGF for LaTeX, SVG, PNG, and JPEG). Although very simple and not relying on any netlist concept, FidoCadJ can be considered a basic electronic design automation program. FidoCadJ uses a file format containing only UTF-8 text, which is very compact and suited for copying and pasting with newsgroups and forum messages. This determined its success, as it is quite versatile for simple mechanical drawings as well as for electronics.
GSL shell offers an interactive user interface that gives access to the GSL collection of mathematical functions. It is based on the powerful and elegant scripting language Lua. GSL shell is not just a wrapper over the C API of GSL, but offers a much more simple and expressive way to use GSL. The objective is to give the user the power to easily access GSL functions without having to write a complete C application. It also has a powerful module to produce plots or almost any kind of graphics based on data or functions.
Ghostscript is a processor for PostScript and PDF files. It can rasterize these files to a wide variety of printers, devices for screen preview, and image file formats. Since applications tend to prepare pages for printing in a high-level format such as PostScript, most Unix users with low-level bitmap printers, such as inkjets, use GhostScript as part of the printing process. In addition, Ghostscript is capable of converting PostScript files, functionality comparable to Adobe Acrobat Distiller, but on the command line. In addition, Ghostscript is used for file import and viewing by a great many other applications, including xv, ImageMagick, gimp, and xdvi. Several GUI wrappers for viewing PostScript and PDF files exist, including GSview, ghostview, gv, ggv, and kghostview. This is far from a comprehensive list.
OpenVRML is a VRML and X3D browser plug-in and C++ toolkit for incorporating VRML/X3D support into applications. It provides VRML97 and Classic VRML X3D parsers, a runtime, and an OpenGL renderer as C++ libraries. The renderer is fully separate from the runtime library so that users can also provide their own renderer. The OpenVRML browser is provided as a D-Bus service, and is embeddable in host applications using XEmbed. The distribution provides both a stand-alone host and a host that runs as a Mozilla plug-in.
mtPaint is a simple GTK+1/2 painting program designed for creating icons and pixel-based artwork. It can edit indexed palette or 24 bit RGB images and offers basic painting and palette manipulation tools. Its main file format is PNG, although it can also handle JPEG, GIF, TIFF, BMP, TGA, XPM, and XBM files.