Wednesday, June 08, 2005

Wavelets Seen Everywhere

As most will know by now, CineForm uses a variation of wavelet compression. What that means is not so important for this discussion, but it is good to know that most compression is either wavelet or DCT (discrete cosine transform) based. Both wavelet and DCT have been around for a very long time, but for historical reasons DCT has been more prevalent (it was easier to put in silicon); DCT is used at the core of many common compressors like DV, DVCPRO, MPEG, and WM9. Despite the historical adoption of DCT, wavelet is considered a better compressor for image data but unfortunately it is not used widely (yet -- we are helping change this.) So it is very amusing to me when I read on several HD forums that CineForm's compression competitors, AVID DNxHD and Canopos HQ, are also attributed to being wavelet compressors -- which they're not. Why would this be, as neither company makes this claim? It seems the CineForm marketing message (with zero advertising dollars from us) has lead people to equate wavelet with high quality (nice, thank you, we totally agree.) So I guess some users assume the solutions of AVID or Canopus are also using wavelets to achieve their own quality claims. They might very well be nice codecs but they are not wavelet based.

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