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From: Bob Friesenhahn <bfriesen@simple.dallas.tx.us>
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To: Joris <joris.at.lebbeke@skynet.be>
Subject: Re: [Tiff] 16-Bit-Per-Channel Lossless Compression
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Status:   

On Wed, 4 Jul 2007, Joris wrote:
>
> Thing is, for photographic data the only real compression that works and make 
> sense both, is lossy compression, is JPEG. Therefore, part of the answer to 
> this problem ought to be more widespread and easier building of a 
> 12bit/channel JPEG compression.
>
> That's doesn't cover the really lossy needs (though on photographic data 
> there is not much such need), and it doesn't cover the really 16bit/channel 
> need, so it's only part of the answer. But a vital part nonetheless.

Your 12bit/channel is sufficient to represent what today's high-end 
image sensors are able to accomplish in the typical ambient 
environment.  The popularity of 16/bit/channel is primarily due to the 
way the samples nicely fit a native CPU data type so they may be 
handled quickly with the minimum of code.  HDR, linear-light, and 
exotic scientific/sensing applications may need many more bits.

Bob
======================================
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/

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