Xvid is an open-source research project focusing on video compression and is a collaborative development effort. All code is released under the terms of the GNU GPL license.
The Xvid video codec implements MPEG-4 Simple Profile and Advanced Simple Profile standards. It permits compressing and decompressing digital video in order to reduce the required bandwidth of video data for transmission over computer networks or efficient storage on CDs or DVDs. Due to its unrivalled quality Xvid has gained great popularity and is used in many other GPLed applications, like e.g. Transcode, MEncoder, MPlayer, Xine and many more.
YACAS is an easy to use, general purpose Computer Algebra System, a program for symbolic manipulation of mathematical expressions. It uses its own programming language designed for symbolic as well as arbitrary-precision numerical computations. The system has a library of scripts that implement many of the symbolic algebra operations; new algorithms can be easily added to the library. YACAS comes with extensive documentation (320+ pages) covering the scripting language, the functionality that is already implemented in the system, and the algorithms we used.
Large-Scale Open-Source Web Search YaCy is a scalable personal web crawler and web search engine. One YaCy installation can store more than 10 million documents, but in a community of search peers YaCy can provide a search index of unlimited size.
Yukon is a set of libraries and applications that are designed to capture realtime videos of OpenGL applications (games). The original design idea is based on Anandtech's FrameGetter, but was extended to suit todays high-performance computers.
E. Raymond. O'Reilly Media, Beijing; Cambridge; Farnham; Köln; Paris; Sebastopol; Taip, 2., überarb. und erw. A. Edition, (2001)With a foreword by Bob Young.