[gdal-dev] RasterIO in paralel

[Stefano Moratto]

Thanks for the suggestion,

I have to read png from openstreetmap. I'm trying to render an A4 paper size
sheet so I have a lot of data to move.
It may be better to divide the area to be read in blocks and to give to each
thread a block. Foreach  block a thread should read all the bands.
Probabilly I should allign the block to the tile's boundary

Stefano

-- 
Dr.Eng. Stefano Moratto
stefano.moratto at gmail.com
stefano.moratto at csiat.it
http://www.csiat.it - Traffic Optimization Software

On Tue, Feb 8, 2011 at 10:48 PM, Even Rouault
<even.rouault at mines-paris.org>wrote:

> Le mardi 08 février 2011 22:41:50, Stefano Moratto a écrit :
> > Hello,
> >           given an opened GDAL dataset, is it possibile to perform
> > gdalrasterio calls for each band in a dedicated thread per band in a
> > thead-safe way?
> > E.g. I have a raster image with 3 band (r,g,b). Since I have 4 core I
> would
> > like to I run a thread for a band r, one for band g and one for band g.
>
> This has been discussed recently. See
> http://lists.osgeo.org/pipermail/gdal-
> dev/2011-January/027567.html and the following messages.
>
> (I'd note that if you process a pixel interleaved image, there are
> optimizations in the GTiff driver to make the fetching of other bands
> almost
> 'free' if you read block by block, so there's probably little to gain, but
> the
> results of your experiments are welcome)
>
> >
> >
> > Regards,
> > Stefano
>
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