Lagarith is an
open source lossless
Lossless compression is a class of data compression that allows the original data to be perfectly reconstructed from the compressed data with no loss of information. Lossless compression is possible because most real-world data exhibits statistic ...
video codec
A video codec is software or hardware that compresses and decompresses digital video. In the context of video compression, ''codec'' is a portmanteau of ''encoder'' and ''decoder'', while a device that only compresses is typically called an '' ...
written by Ben Greenwood. It is a
fork
In cutlery or kitchenware, a fork (from la, furca 'pitchfork') is a utensil, now usually made of metal, whose long handle terminates in a head that branches into several narrow and often slightly curved tine (structural), tines with which one ...
of the code of
HuffYUV and offers better compression at the cost of greatly reduced speed on uniprocessor systems. Lagarith was designed and written with a few aims in mind:
;Speed: while not as fast as HuffYUV, it still outperforms most other lossless video codecs when it comes to encoding times,
although decoding speed may be slower. Recent versions also support parallelizing on multi-processor systems.
;
Color-space support: color-space conversions can cause rounding errors, introducing data loss, contrary to the ideal of lossless video compression. Lagarith attempts to avoid this problem by supporting
YV12
YUV is a color model typically used as part of a color image pipeline. It encodes a color image or video taking human perception into account, allowing reduced bandwidth for chrominance components, compared to a "direct" RGB-representation. ...
,
YUY2
YUV is a color model typically used as part of a color image pipeline. It encodes a color image or video taking human perception into account, allowing reduced bandwidth for chrominance components, compared to a "direct" RGB-representation. ...
,
RGB
The RGB color model is an additive color model in which the red, green and blue primary colors of light are added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three addi ...
, and
RGBA
RGBA stands for red green blue alpha. While it is sometimes described as a color space, it is actually a three-channel RGB color model supplemented with a fourth ''alpha channel''. Alpha indicates how opaque each pixel is and allows an image to ...
colorspaces.
;
Keyframes: disallowing inter-prediction means that each frame can be separately decoded. This makes cutting, joining and seeking much easier.
These three things, as well as being more efficient at compression than HuffYUV, make it a codec useful for the video editing stage.
References
External links
Official Website
{{Compression Software Implementations
Free video codecs
Lossless compression algorithms
Video codecs