[gdal-dev] warp taking time

[Chaitanya kumar CH]

Adiba,

I noticed that your source and target projections are same. Why not use
gdalbuildvrt and gdal_translate and skip the warping process? You create a
virtual mosaic (and assign the projection if needed) with buildvrt. You can
create a tiff file from the vrt file using gdal_translate.


On Mon, Jul 14, 2014 at 11:12 AM, adiba nizami <adiba.nizami at gmail.com>
wrote:

> Sorry for the late reply. Here is the command i  gave :
>
> gdalwarp --config GDAL_CACHEMAX 512 -s_srs "+proj=aea +lat_1=28 +lat_2=12
> +lat_0=20 +lon_0=87 +x_0=2000000 +y_0=2000000 +ellps=WGS84 +datum=WGS84
> +units=m +no_defs" -t_srs "+proj=aea +lat_1=28 +lat_2=12 +lat_0=20
> +lon_0=87 +x_0=2000000 +y_0=2000000 +ellps=WGS84 +datum=WGS84 +units=m
> +no_defs" -te -138559.10 571316.50 3010515.63 4012751.95 -tr 18 18 -wm 512
> -co "BIGTIFF=YES" -srcnodata 255 -dstnodata 255  file1.tif file2.tif .....
> file28.tif output.tif
>
>
>
> On Thu, Jul 10, 2014 at 7:23 PM, Thornton, Michele M. <thorntonmm at ornl.gov
> > wrote:
>
>>  Hello,
>>
>>
>>
>> I’m interested in this thread.  One comment I can add about gdal_merge.py
>> is that it does not properly handle nodata values from the full (padded)
>> extent of the input files.  gdalwarp, which can be VERY slow, does handle
>> the nodata values correctly.
>>
>>
>>
>> Michele Thornton
>>
>>
>>
>> *From:* gdal-dev-bounces at lists.osgeo.org [mailto:
>> gdal-dev-bounces at lists.osgeo.org] *On Behalf Of *bas smit
>> *Sent:* Thursday, July 10, 2014 7:52 AM
>> *To:* Chaitanya kumar CH
>> *Cc:* gdal dev
>> *Subject:* Re: [gdal-dev] warp taking time
>>
>>
>>
>> I am wondering why you are using gdalwarp for mosaicing images having same
>> projection instead of gdal_merge.py?
>>
>>
>>
>> Bas Smit
>>
>>
>>
>> On Thu, Jul 10, 2014 at 7:14 PM, Chaitanya kumar CH <
>> chaitanya.ch at gmail.com> wrote:
>>
>> garfy,
>>
>>
>>
>> Please provide the gdalwarp command you used. Did you modify
>> GDAL_CACHEMAX?
>>
>>
>>
>> On Thu, Jul 10, 2014 at 3:26 PM, garfy <adiba.nizami at gmail.com> wrote:
>>
>> Dear All,
>>
>> I am trying to generate mosaic of 28 input images using *gdalwarp*.
>> All are in same projection. It has taken 5 days to generate the final
>> output.
>> Please find the gdalinfo of input and output attached. The input files are
>> passed to warp in the order in which the gdalinfo is present in the
>> attachement.
>>
>> Any input on improving the time would be really helpful.
>>
>>
>> Thanks
>> input_files_gdalinfo.txt
>> <
>> http://osgeo-org.1560.x6.nabble.com/file/n5150453/input_files_gdalinfo.txt
>> >
>> final_output_gdalinfo.txt
>> <
>> http://osgeo-org.1560.x6.nabble.com/file/n5150453/final_output_gdalinfo.txt
>> >
>>
>>
>>
>>
>>
>> --
>> View this message in context:
>> http://osgeo-org.1560.x6.nabble.com/warp-taking-time-tp5150453.html
>> Sent from the GDAL - Dev mailing list archive at Nabble.com.
>> _______________________________________________
>> gdal-dev mailing list
>> gdal-dev at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>>
>>
>>
>>
>>
>> --
>> Best regards,
>> Chaitanya kumar CH.
>>
>> +91-9494447584
>> 17.2416N 80.1426E
>>
>>
>> _______________________________________________
>> gdal-dev mailing list
>> gdal-dev at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>>
>>
>>
>> _______________________________________________
>> gdal-dev mailing list
>> gdal-dev at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/gdal-dev
>>
>
>
>
> --
> Regards,
> Adiba Khan
>



-- 
Best regards,
Chaitanya kumar CH.

+91-9494447584
17.2416N 80.1426E
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/gdal-dev/attachments/20140714/55d1de53/attachment-0001.html>