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.
album is a free HTML/XHTML photo album and gallery generator that supports themes/skins. You can choose different themes or write your own to get different layouts and styles. It creates all your thumbnails (including directory thumbnails) and descends into directories so you can organize your photos. See the home page for more examples. album is also multi-lingual, with many languages being added all the time. N.B.: The purchase link is provided for donations; the software does not cost anything.
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.
KVEC is a command line tool that allows you to convert raster graphics to vector graphics. KVEC is designed for 32 bit operating systems and runs on Win32, OS/2, HP-UX, NEXTSTEP, Linux, IRIX, AIX 4.x, Macintosh and BeOS. Docs are available in English and German. The shareware version is available for 30 day trial.
QCad is a powerful but easy to use 2D CAD program for Linux, Windows, and Mac OS X. It uses DXF as its standard file format. While other CAD packages are often rather complicated to use, QCad tries to stay comfortable, and even an absolute beginner can create professional drawings with a minimum of effort.
makethumbs is a Bourne shell script which creates static HTML image galleries suitable for web or CDROM presentations. It is designed for portability and depends on the fewest possible helper programs. You can simply run makethumbs in a directory of JPEGs and get a usable set of web pages. If you have the time, you can add captions, descriptions, and create a dotrc file to completely change the look and feel of the generated gallery. A small helper script, rotate.sh, is also available to easily fix rotated images.
Jpgtn generates smaller JPEGs from larger ones. It can work in batches and create new files with names based on the names of the source files. It can dump a single thumbnail to stdout for use with pipelines or CGI programs. Thumbnail size and quality can be controlled by switches on the command line. There is no maximum "thumbnail" size, so it can be useful for creating images suitable for web publishing from very large images such as those taken with a good digicam.
LinPHA is an easy-to-use, multilingual, flexible photo/image archive/album/gallery written in PHP. It uses an SQL database (MySQL/PostgreSQL/SQLite) to store information about your pictures. It comes with an HTML-based installer, so you don't need experience in setting up SQL databases. Thumbnails are created as needed and stored in the SQL DB. It features complete user management, top ten statistics, hidden albums, different themes, slideshow, filemanager, uploader, watermarks, benchmark, printing, and more.