mail at christophersmart.com
Fri Jan 8 22:25:45 UTC 2010
2010/1/9 Tony Nelson <tonynelson at georgeanelson.com>:
> According to that reference, Dirac is a typical lossy encoding method.
> The loss is introduced by the Quantization step, while the compression
> comes from entropy-coding the quantized (decimated) data with
> Arithmetic Coding.
Yes, that's with lossy compression on top of wavelets, as opposed to
discrete cosine transformations, according to Wikipedia.
However the website (and BBC site) say that it can employ lossless compression:
"Dirac has the capability of compressing high resolution files for
production, compression for broadcast content, and compression for web
2.0 applications. Compression can be either lossless or visually
When I played with it a while back, I'm pretty sure there was an
option for lossless.
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