[Gdal-dev] caching of the blocks

[Stephane Routelous]

Hi Frank,

I've done a performance test for comparing RasterIO vs ReadBlock

I'm reading a big geotiff image (8100x7200)

the results are : RasterIO=8752ms ReadBlock=6776ms

Stephane

-----Original Message-----
From: Frank Warmerdam [mailto:warmerdam at pobox.com]
Sent: Friday, August 27, 2004 1:39 PM
To: Stephane Routelous
Cc: 'gdal-dev at remotesensing.org'
Subject: Re: [Gdal-dev] caching of the blocks


Stephane Routelous wrote:
> Hi Frank,
> 
> Thanks a lot for your quick answer.
> I need to use the ReadBlock to have the best performances, and also
because
> of the resampling.
> I will continue to use it and implement my own cache mecanism.
> 

Stephane,

Note, you can call RasterIO() at 1:1 resolution on exact block boundaries
and you will have essentially the same performance but with GDAL block
caching kicking in.

Best regards,
-- 
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