[gdal-dev] oblique cuts on a raster using python GDAL

[Javier Jimenez Shaw]

This is working for me (and also in gdal 3.8.0):

gdalwarp 3635_rasters_agreges.jp2 salida.tif -cutline
geometry_extraction.shp -crop_to_cutline -dstnodata 0 -cl
geometry_extraction -overwrite -of GTiff

About the "white" pixels inside the image, it could be that a single band
has a value of 0 (not that strange). Then it is transparent, and you see
the background color. (to avoid those "color misunderstandings" I have a
pink background color, that is not white).

On Mon, 6 Nov 2023 at 12:35, Naima Dambrine <naima.etienne at gmail.com> wrote:

> Hi Javier,
>
> Thank you, good news ...
>
> I'm on Ubuntu 20.04 with gdal 3.6.2. Yes, the original raster format is
> JP2, but my output format is GTiff. Here is exactly what I do :
>
> cut_ds = gdal.Warp(outfile, jp2_ds, format='GTiff',
> cutlineDCName=shape_file_path,
> cropToCutline=True,
> copyMetadat=True,
> dstNodata=0)
>
> What I see is that there are still black pixels around the image, as well
> as white pixels inside the image.
> Another point to consider is that, despite the use of compression, the
> output file is 75.3 MB, compared with around 14 MB with a JP2 format. Why
> is this?
>
> my output :
>
>
>
>
> Le lun. 6 nov. 2023 à 11:33, Javier Jimenez Shaw <j1 at jimenezshaw.com> a
> écrit :
>
>> Hi Naima
>>
>> I have been testing with your dataset. To me, using the GDAL in Ubuntu
>> 22.04 (3.4.1) seems to be a problem with the JP2 output format. If you
>> output as geotiff it works fine.
>>
>> On Sun, 5 Nov 2023 at 19:43, Rahkonen Jukka via gdal-dev <
>> gdal-dev at lists.osgeo.org> wrote:
>>
>>> Hi,
>>>
>>>
>>>
>>> Please add gdalinfo of the source image. Even better if you can share
>>> the image.
>>>
>>>
>>>
>>> -Jukka Rahkonen-
>>>
>>>
>>>
>>> *Lähettäjä:* gdal-dev <gdal-dev-bounces at lists.osgeo.org> *Puolesta *Naima
>>> Dambrine via gdal-dev
>>> *Lähetetty:* sunnuntai 5. marraskuuta 2023 17.35
>>> *Vastaanottaja:* gdal-dev at lists.osgeo.org
>>> *Aihe:* [gdal-dev] oblique cuts on a raster using python GDAL
>>>
>>>
>>>
>>> Hi ,
>>>
>>>
>>>
>>> I have problems with oblique cuts on a raster using python GDAL (3.6.2)
>>>
>>>
>>>
>>> - with this line i obtain black borders around :
>>>
>>> gdal.warp('raster-dst' , raster-src',
>>> cutLineDSName='geometry-extraction.shp', cropToCutline=True)
>>>
>>>
>>>
>>> - with this one, the crop is not clean on closer inspection: residual
>>> black pixels around image and white pixels appear in the image.
>>>
>>> gdal. warp( 'raster-dst' , raster-src',
>>> cutLineDSName='geometry-extraction.shp', cropToCutline=True,
>>> copyMetaData=True, dstNodata=0)
>>>
>>>
>>> I tried, without success, to refine with outputBounds=[minX, maxX, minY,
>>> maxY], under QGIS directly ….
>>> I've run out of ideas :/
>>> A (naive) question comes to mind: Is it possible to make oblique cuts
>>> with gdal.warp() & co?
>>>
>>> Naïma
>>> _______________________________________________
>>> gdal-dev mailing list
>>> gdal-dev at lists.osgeo.org
>>> https://lists.osgeo.org/mailman/listinfo/gdal-dev
>>>
>>
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