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Message-ID: <3B585339.651C9C7C@cp10.es.xerox.com>
Date: Fri, 20 Jul 2001 08:50:17 -0700
From: Terry Wells <twells@cp10.es.xerox.com>
Organization: Xerox Corporation, El Segundo CA
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To: Bruno LEDOUX <bruno_ledoux@binuscan.com>
CC: Sean Finn <sean@mediacy.com>, "tiff@olympiakos.com" <tiff@olympiakos.com>
Subject: Re: LZW TIFFReadScanline woes
References: <B77DB9F7.659B%bruno_ledoux@binuscan.com>
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The optimizer in VC++ 5 had quite a few bugs in it.  VC++ 6 seems much better.

Back to the original problem...

Sean: You said that you were subsampling the image by skipping scanlines when
reading.  Perhaps something to try would be to read all the scanlines into your
buffer even though you ignore some of them.  If the lzw decompressor had a bug
where it failed to properly decode lines out of order, this would workaround it.

Terry


Bruno LEDOUX wrote:

> On 19/07/01 23:29, "Sean Finn" <sean@mediacy.com> wrote:
>
> Hi,
>
> I remember that I had problems with LZW compression/decompression
> When compiling in release mode ie with all optimizations on.  When I turned
> them off for the tiff_lzw.c  file everything worked. I don't know what
> compiler you are using but for me it occurred with VC++ 5.
>
> Hth,
>
> bruno

