From: warmerdam@pobox.com (Frank Warmerdam)
Date: Mon, 29 Sep 2003 10:17:11 -0400
Subject: [Tiff] performance on windows platform
In-Reply-To: <001701c3866b$e05cd9f0$240310ac@Zuse>
References: <001701c3866b$e05cd9f0$240310ac@Zuse>
Message-ID: <3F783EE7.10401@pobox.com>

Bernd Stahlbock wrote:
> Dear list,
> 
> 
> tifflib is a multi platform solution, so I'm wondering how good the
> performance on windows 2000 systems is. Is there a possibility to change
> it myself to windows memory mapped files or something? Did somebody
> things like this? What do you think will the performance improvement be?

Bernd,

The default IO implementation for libtiff on Win32 platforms includes
support for memory mapped IO.  I am not sure whether memory mapped IO
is ever used by defaut, but you can force it to be used by including the
"m" flag in the access string to TIFFOpen().

eg.

   TIFF *tiff;

   tiff = TIFFOpen( "abc.tif", "rm" );

Best regards,

-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam@pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent



