[gdal-dev] gdal_contour stuck in processing?

[Chaitanya kumar CH]

Graeme,

"gdalinfo -stats dtm.tif" shows "Min=1093360681.000 Max=3351465984.000" for
the pixel values. That would mean you are asking for 225810530 levels; lots
of tightly placed contours. I don't think Shapefile format can accommodate a
vector datasource of that size. Based on the histogram, it's better to use
the -fl option with gdal_contour.

On Mon, Oct 24, 2011 at 11:27 AM, Graeme Merrall <graeme at inetix.com.au>wrote:

> You can download it from http://dl.dropbox.com/u/5657619/dtm.tif  Only
> 9.6Mb
>
> Cheers,
>  Graeme
>
>
> On Mon, Oct 24, 2011 at 3:02 PM, Chaitanya kumar CH <
> chaitanya.ch at gmail.com> wrote:
>
>> Graeme,
>>
>> Can you provide a small sample image for testing?
>>
>>
>> On Mon, Oct 24, 2011 at 9:20 AM, Graeme Merrall <graeme at inetix.com.au>wrote:
>>
>>> Correction, the cmdline was "gdal_contour -a ELEL -i 10.0 dtm.tif
>>> dtm-10m.shp"
>>>
>>>
>>>
>>> On Mon, Oct 24, 2011 at 1:58 PM, Graeme Merrall <graeme at inetix.com.au>wrote:
>>>
>>>> Apologies for the delay in replying.
>>>>
>>>> I ran the same command with 10m spacing "gdal_contour -a ELEL -i 1.0
>>>> dtm.tif dtm-10m.shp" and the same issue occurred.   I also ran the DTM
>>>> through gdal_translate to add projection info just in case. Note this is
>>>> gdal_1.8.1 running on Ubuntu Lucid not from deb's but a custom compile
>>>>
>>>> The same symptoms occur, it gets to around 7% or so then hangs. Load
>>>> goes through the roof.
>>>>
>>>> Ran it through strace and seems to get stuck in massive loop with
>>>> calling brk()
>>>>
>>>> Cheers,
>>>>  Graeme
>>>>
>>>> On Thu, Oct 13, 2011 at 4:03 PM, Chaitanya kumar CH <
>>>> chaitanya.ch at gmail.com> wrote:
>>>>
>>>>> Graeme,
>>>>>
>>>>> Can you try again with a much larger interval?
>>>>>
>>>>>  On Thu, Oct 13, 2011 at 6:32 AM, Graeme Merrall <graeme at inetix.com.au
>>>>> > wrote:
>>>>>
>>>>>> I'm trying out gdal_contour just to see what falls out of it as an
>>>>>> experiment.  I've noticed it seems to get to "0.."  e.g. 7% or so, and
>>>>>> then seems to hang.  I'm trying it on a relatively small DTM
>>>>>>
>>>>>> The cmdline is pretty simple "gdal_contour -a ELEL -i 1.0
>>>>>> dtm_11072101.tif dtm-1m.shp"
>>>>>>
>>>>>> and gdalinfo gives the following info  about the image
>>>>>> Driver: GTiff/GeoTIFF
>>>>>> Files: dtm_11072101.tif
>>>>>>      dtm_11072101.tfw
>>>>>> Size is 1000, 2500
>>>>>> Coordinate System is `'
>>>>>> Origin = (488000.000000000000000,7198000.000000000000000)
>>>>>> Pixel Size = (2.000000000000000,-2.000000000000000)
>>>>>> Metadata:
>>>>>>  TIFFTAG_XRESOLUTION=200
>>>>>>  TIFFTAG_YRESOLUTION=200
>>>>>>  TIFFTAG_RESOLUTIONUNIT=3 (pixels/cm)
>>>>>> Image Structure Metadata:
>>>>>>  INTERLEAVE=BAND
>>>>>> Corner Coordinates:
>>>>>> Upper Left  (  488000.000, 7198000.000)
>>>>>> Lower Left  (  488000.000, 7193000.000)
>>>>>> Upper Right (  490000.000, 7198000.000)
>>>>>> Lower Right (  490000.000, 7193000.000)
>>>>>> Center      (  489000.000, 7195500.000)
>>>>>> Band 1 Block=1000x2 Type=UInt32, ColorInterp=Gray
>>>>>>
>>>>>> I admit I'm at a loss as to how to proceed/troubleshoot so any
>>>>>> pointers gratefully received. I tried popping it through
>>>>>> gdal_translate to add a projection but it seems to have the same issue
>>>>>>
>>>>>> Cheers,
>>>>>>  Graeme
>>>>>> _______________________________________________
>>>>>> 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
>>>>>
>>>>
>>>>
>>>
>>
>>
>> --
>> Best regards,
>> Chaitanya kumar CH.
>>
>> +91-9494447584
>> 17.2416N 80.1426E
>>
>
>


-- 
Best regards,
Chaitanya kumar CH.

+91-9494447584
17.2416N 80.1426E
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