[GRASS-user] Importing USGS' wrs2_descending Shapefile

[Markus Metz]

On Tue, Feb 24, 2015 at 3:28 PM, Nikos Alexandris
<nik at nikosalexandris.net> wrote:
> Flash-backing on this one:
>
> [..]
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> Markus M:
>
>> Yes, overlapping areas can be represented as a topological model
>> through M:N mapping: each area can belong to several categories,
>> several areas can have the same category. If you want to get the
>> coverage for a particular Landsat scene, just select the path and row
>> with where="PATH = x and row = y". See also the manual of v.buffer for
>> a similar example.
>
>
> So, I guess I'll forget the idea to fully automatise the process of Landsat
> border trimming? Can't we just have all of the Path-Row tiles ready in a
> compressed GRASS format? Some sort of packed ASCII file which can be easily
> imported?  No other ideas?

I think you can trim the borders using the Landsat raster data
themselves: according to the metadata, valid numbers are > 0. If the
sum of all bands is zero, the pixel is outside.

Markus M
>
> Nikos
>
>
> Markus N:
>
>>>> Hence, you need to maintain them (AFAIK it is the -c option in
>>>> v.in.ogr).
>>>> Please correct me if I am wrong.
>
>
>> For this shapefile, original polygons can not be maintained (incorrect
>> boundaries, centroids exceeding number of areas).
>
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> [..]
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