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- Path: sparky!uunet!ogicse!das-news.harvard.edu!cantaloupe.srv.cs.cmu.edu!news
- From: rwb@kurn.VI.RI.CMU.EDU (Robert Berger)
- Newsgroups: comp.sys.mac.misc
- Subject: Re: semi-technical QuickTime info required...
- Message-ID: <BxG1LA.7tG.2@cs.cmu.edu>
- Date: 9 Nov 92 10:10:21 GMT
- Article-I.D.: cs.BxG1LA.7tG.2
- References: <BxF8nt.5zw@world.std.com>
- Sender: news@cs.cmu.edu (Usenet News System)
- Organization: School of Computer Science, Carnegie Mellon
- Lines: 13
- Nntp-Posting-Host: kurn.vi.ri.cmu.edu
-
- In article <BxF8nt.5zw@world.std.com> ivanski@world.std.com (Ivan M
- CaveroBelaunde) writes:
- > It's a VQ (Vector Quantization) scheme, which is similar to finding an
- > optimum CLUT for an image. You basically have a color map (called a
- > codebook) and you map each pixel to the closest color in the codebook.
-
- Not exactly. In VQ, you map blocks of MULTIPLE pixels to codebook entries.
-
- For example, each codebook entry might be a 3x2 group of pixels.
-
- VQ has the property that the compression is many times slower than the
- decompression. Finding a codebook that works well for a set of images
- requires lots of computation.
-