Compressed with Cinepak, quality 40%

Cinepak is a video codec, developed by Radius Inc to accommodate 1x (150 kbyte/s) CD-ROM transfer rates. Image File history File links Cinepak. ... Image File history File links Cinepak. ... A video codec is a device or software module that enables the use of data compression for digital video. ... Radius was a computer hardware firm founded by Burrell Smith, Andy Hertzfeld, Mike Boich, Matt Carter, Alain Rossman and other members of the original Mac team specialising in Macintosh equipment. ... The CD-ROM (an abbreviation for Compact Disc Read-Only Memory (ROM)) is a non-volatile optical data storage medium using the same physical format as audio compact discs, readable by a computer with a CD-ROM drive. ...

It was the primary video codec of early versions of QuickTime and Microsoft Video for Windows, but was later superseded by Sorenson Video, Intel Indeo, and most recently MPEG-4 and h.264. However, movies compressed with Cinepak are generally still playable in most media players. QuickTime is a multimedia technology developed by Apple Computer, capable of handling various formats of digital video, sound, text, animation, music, and immersive panoramic (and sphere panoramic) images. ... Video for Windows was a multimedia technology developed by Microsoft that allowed Microsoft Windows to play digital video. ... The Sorenson codec (also known as Sorenson Video Codec, Sorenson Video Quantizer or SVQ) is a digital video codec devised by the company Sorenson Media and used by Apples QuickTime and the newest version of Macromedia Flash, a special version called Sorenson Spark. ... Indeo is a video codec originally developed by Intel and now owned by Ligos. ... MPEG-4, introduced in late 1998, is the designation for a group of audio and video coding standards and related technology agreed upon by the ISO/IEC Moving Picture Experts Group (MPEG). ... H.264 is a high compression digital video codec standard written by the ITU-T Video Coding Experts Group (VCEG) together with the ISO/IEC Moving Picture Experts Group (MPEG) as the product of a collective partnership effort known as the Joint Video Team (JVT). ...

Cinepak is based on vector quantization, which is a significantly different algorithm from the discrete cosine transform (DCT) algorithm used by most current codecs (in particular the MPEG family, as well as JPEG). This permitted implementation on relatively slow CPUs, but tended to result in blocky artifacting at low bitrates. In data compression, vector quantization is a quantization technique often used in lossy data compression in which the basic idea is to code or replace with a key, values from a multidimensional vector space into values from a discrete subspace of lower dimension. ... 2-D DCT compared to the DFT The discrete cosine transform (DCT) is a Fourier-related transform similar to the discrete Fourier transform (DFT), but using only real numbers. ... The Moving Picture Experts Group or MPEG is a working group of ISO/IEC charged with the development of video and audio encoding standards. ... A photo of a flower compressed with successively lossier compression ratios from left to right. ... In telecommunications and computing, bit rate (sometimes written bitrate) is the frequency at which bits are passing a given (physical or metaphorical) point. It is quantified using the bit per second (bit/s) unit. ...

Cinpepak divides a movie into key images and intra-coded images. Each image is divided into a number of horizontal bands which have individual 256-color palettes transferred in the key images. Each band is subdivided into 4x4 pixel blocks. The compressor uses vector quantization to determine the one or two band palette colors which best match each block and encodes runs of blocks as either one color byte or two color bytes plus a 16-bit vector which determines which pixel gets which color. The data rate can be controlled within a narrow range by adjusting the rate of key versus intra-coded frames and by adjusting the permitted error in each block and the block run-length. In data compression, vector quantization is a quantization technique often used in lossy data compression in which the basic idea is to code or replace with a key, values from a multidimensional vector space into values from a discrete subspace of lower dimension. ...

External links

• Compression Technologies, Inc. - current developers of Cinepak