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From: lucio@proxima.alt.za
To: 9fans@cse.psu.edu
Cc: eugene@dynagen.co.za
Subject: Re: [9fans] PNG and APE (cntd)
Date: Thu, 27 Apr 2006 19:51:33 +0200	[thread overview]
Message-ID: <f61a32e00d89b34c170983d55c3873e6@proxima.alt.za> (raw)
In-Reply-To: <44506363.3070407@gmail.com>

> I don't know if I understood correctly your question, but although GIF
> uses LZW instead of zlib (LZ77 iirc), it can stand only for 256
> different colors - hence it my be smaller than PNG, as PNG allows 32bit
> colors fine (being 8 for alpha).

The question was poorly phrased.  But yes, the comparison is between
PNG and GIF, specifically, because if baffled me when somebody showed
me figures that suggested the same image in PNG was larger than in
GIF.

I can only presume that PNG encoders increase the pixel depth, for
whatever reason.

And, BTW, PNG allows 16-bit per colour, a 48-bit depth per pixel.
Thanks to libpng, my "npng" can render these as 24-bit images.

++L



  reply	other threads:[~2006-04-27 17:51 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-04-27  4:47 lucio
2006-04-27  6:23 ` Lluís Batlle i Rossell
2006-04-27 17:51   ` lucio [this message]
2006-04-27 18:24     ` Lluís Batlle i Rossell
2006-04-27 18:28     ` Charles Forsyth
2006-04-27 19:26       ` Jack Johnson
2006-04-27 19:58         ` Steve Simon
2006-04-27 21:13           ` Lluís Batlle i Rossell
2006-04-27 22:05             ` Charles Forsyth
2006-04-28  5:00               ` lucio
2006-04-28 18:31                 ` jmk
2006-04-27 20:02         ` Bruce Ellis
2006-04-27 19:59       ` lucio
2006-04-27  6:36 ` andrey mirtchovski
2006-04-27  6:39   ` andrey mirtchovski
2006-04-27 11:43   ` Lluís Batlle
2006-04-27 11:53     ` Harri Haataja
2006-04-27 12:25 ` Russ Cox
2006-04-27 18:18   ` lucio
2006-04-27 18:27     ` andrey mirtchovski
2006-04-27 19:56       ` lucio
2006-04-27 12:25 ` Russ Cox

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