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<title>sane-devel: Re: 16 bit per sample support</title>
<h1>Re: 16 bit per sample support</h1>
<b>Jonathan A. Buzzard</b> (<a href="mailto:jab@hex.prestel.co.uk"><i>jab@hex.prestel.co.uk</i></a>)<br>
<i>Mon, 05 Apr 1999 23:02:56 +0000</i>
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<li> <b>Next message:</b> <a href="0090.html">David Mosberger-Tang: "Re: 16 bit per sample support"</a>
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<a href="mailto:adilger@enel.ucalgary.ca">adilger@enel.ucalgary.ca</a> said:<br>
<i>&gt; If you are doing things like adding images together, just assuming</i><br>
<i>&gt; that 12 bits is better than the stored 16 bits is pointless, because</i><br>
<i>&gt; if you are adding more than 16 images or doing other mathematical</i><br>
<i>&gt; operations you will overflow anyways, and you are probably better off</i><br>
<i>&gt; using a 32-bit fixed point representation anyways. The important</i><br>
<i>&gt; thing is that you know what bit-depth the original data was in, and</i><br>
<i>&gt; the back-end will know this, and the front-end should save it. PNG</i><br>
<i>&gt; does this, and it is being used for medical image storage. </i><br>
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In a world where everyone is using PNG and the front end stores the<br>
bit depth of the original image this is fine. Not everyone lives in<br>
a perfect world.<br>
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Fixed point representation in image processing is a last resort, and adding<br>
images is only an example, intended to be simplistic so everyone could<br>
grasp the concept.<br>
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<p>
JAB.<br>
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--
Jonathan A. Buzzard Email: <a href="mailto:jab@hex.prestel.co.uk">jab@hex.prestel.co.uk</a>
Northumberland, United Kingdom. Tel: +44(0)1661-832195
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<li> <b>Next message:</b> <a href="0090.html">David Mosberger-Tang: "Re: 16 bit per sample support"</a>
<li> <b>Previous message:</b> <a href="0088.html">Jonathan A. Buzzard: "Re: 16 bit per sample support"</a>
<li> <b>In reply to:</b> <a href="0082.html">Andreas Dilger: "Re: 16 bit per sample support"</a>
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<li> <b>Next in thread:</b> <a href="0085.html">Nick Lamb: "Re: 16 bit per sample support"</a>
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