[gdal-dev] Re: CUDA PyCUDA and GDAL

[Hisaji ONO]

Hello.

 Is there no gap or noises in image data generated by this
method? 


 Regards.

--- Doug_Newcomb at fws.gov wrote:

> 
> 
> 
> 
> >Hi Doug,
> 
> >I finally tried your parameters and they did work
> fine for me also.  I
> >had something like  hundred geotiffs, 400 MB each,
> and I was pushing
> >them to bigtiff mosaic. I tried first with your
> *.tif selection and then
> >again by using a virtual raster file as source,
> created from Mapserver
> >tileindex shapefile with gdalbuildvrt. My Windows
> computer was handling
> >about 20 GB/hour with cubic resampling (-rc) this
> time.  Parameters
> ?-wo "SKIP_NOSOURCE"  --config "GDAL_CACHEMAX=500"
> -wm=5000
> >seem to have a big influence on efficiency.  I
> wonder if there are some
> >rules of thumb for selecting values of
> GDAL_CACHEMAX and -wm.  You said
> >cachemax is good to be close to the maximum input
> file size, how about
> >-wm?
> 
> >-Jukka Rahkonen-
> 
> Jukka,
>       I remember seeing someone mention on the
> mailing list ( Can't recall
> who at the moment) that setting GDAL_CACHEMAX close
> to the maximum size of
> the input files gave the best performance.  I did
> try bumping GDAL_CACHEMAX
> up to 2000 to see what would happen ( while dropping
> -wm down to 3000, only
> 6GB of RAM on that computer) , but none of the input
> files I was processing
> were larger than 500MB and I saw no increase in
> performance.  For the -wm
> parameter, I just gave it the rest of the RAM
> available on the computer,
> and I did not benchmark while varying that number.
> 
> Doug
> 
> 
> Doug Newcomb
> USFWS
> Raleigh, NC
> 919-856-4520 ext. 14 doug_newcomb at fws.gov
>
---------------------------------------------------------------------------------------------------------
> 
> The opinions I express are my own and are not
> representative of the
> official policy of the U.S.Fish and Wildlife Service
> or Dept. of the
> Interior.   Life is too short for undocumented,
> proprietary data formats.
> 
> 
>                                                     
>                   
>              "Rahkonen Jukka"                       
>                   
>              <Jukka.Rahkonen at m                      
>                   
>              mmtike.fi>                             
>                    To
>                                       
> <gdal-dev at lists.osgeo.org>,     
>              12/07/2009 05:06         
> <Doug_Newcomb at fws.gov>          
>              AM                                     
>                    cc
>                                                     
>                   
>                                                     
>               Subject
>                                        Re: CUDA
> PyCUDA and GDAL        
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> 
> 
> 
> >  <Doug_Newcomb <at> fws.gov> writes:
> >
> > Hi Folks,Here's the gdal command (gdal 1.6.2) I
> used to merge ~3500 1
> meter NAIP
> > quarter quads (uncompressed geotiff TIFF) in 3 UTM
> projections into
> one Bigtiff Image
> > in the USGS Albers projection.  It took about 15
> hours ( on a 3 year
> old Intel Core2
> > Duo 64 bit Centos 5.3 Linux box with 6GB RAM) and
> created an
> uncompressed, tiled,
> > bigtiff file of 485 GB. About 32 GB/hr.
> > gdalwarp -t_srs "+proj=aea +lat_1=29.5+lat_2=45.5
> +lat_0=23.0
> +lon_0=-96
> > +x_0=0 +y_0=0 +ellps=GRS80 +datum=NAD83 +units=m
> no_defs <>"
> > -wo "SKIP_NOSOURCE"  --config "GDAL_CACHEMAX=500"
> -wm=5000
> > -co "TILED=YES" */*.tif
> /biggis/albers/nc_naip2008.tif
> >
> > In the above command, -t_srs "+proj=aea
> +lat_1=29.5 +lat_2=45.5
> +lat_0=23.0
> > +lon_0=-96 +x_0=0 +y_0=0 +ellps=GRS80 +datum=NAD83
> +units=m no_defs
> <>"
> > indicates the target projection, -wo
> "SKIP_NOSOURCE" don't write
> > in areas for which there is no data for the
> current file,
> > --config "GDAL_CACHEMAX=500" set the cache memory
> at 500MB ( set this
> close
> > to the maximum input file size), -wm=5000 set the
> warp memory to
> 5000MB ,
> > -co "TILED=YES" create a tiled tiff as output,
> */*.tif, use all of the
> tiffs
> > in all of the subdirectories as input files ( in
> this case there was
> one
> > directory for each of the 3 utm zones) ,
> /biggis/albers/nc_naip2008.tif,
> > the output file name and location.
> >
> 
> Hi Doug,
> 
> I finally tried your parameters and they did work
> fine for me also.  I
> had something like  hundred geotiffs, 400 MB each,
> and I was pushing
> them to bigtiff mosaic. I tried first with your
> *.tif selection and then
> again by using a virtual raster file as source,
> created from Mapserver
> tileindex shapefile with gdalbuildvrt. My Windows
> computer was handling
> about 20 GB/hour with cubic resampling (-rc) this
> time.  Parameters
> -wo "SKIP_NOSOURCE"  --config "GDAL_CACHEMAX=500"
> -wm=5000
> seem to have a big influence on efficiency.  I
> wonder if there are some
> rules of thumb for selecting values of GDAL_CACHEMAX
> and -wm.  You said
> cachemax is good to be close to the maximum input
> file size, how about
> -wm?
> 
> -Jukka Rahkonen-
> > _______________________________________________
> gdal-dev mailing list
> gdal-dev at lists.osgeo.org
> http://lists.osgeo.org/mailman/listinfo/gdal-dev