[postgis-devel] [WKTRaster] Setting properties on a raster

[David Zwarg]

Another thing about properties:

There is no ST_GeoReference method (currently), which is in the 0.1.6d
spec.  However, there is an ST_gdalgeotransform and an
ST_esriworldfile method.  Are these alternate/vendor specific
implementations, and ST_GeoReference is just eerily similar, or should
one of them be renamed?  I was also thinking about writing the setter,
but wanted to make sure I wasn't stepping on ML's toes -- the task is
assigned to him on the planning page.

Thanks,
Zwarg

On Sun, Feb 21, 2010 at 2:37 PM, David Zwarg <dzwarg at avencia.com> wrote:
> Sounds good to me, I'll change the spec.
>
> z
>
> On Sun, Feb 21, 2010 at 2:26 PM, Pierre Racine
> <Pierre.Racine at sbf.ulaval.ca> wrote:
>>>I'm looking at setting the properties of a raster.  I managed to
>>>figure out how to set the SRID pretty easily:
>>>http://trac.osgeo.org/postgis/ticket/423
>>
>> This is very great Zwarg!
>>
>>>I'm thinking about ST_SetPixelType now, and I'm wondering how you want
>>>to handle the data conversions.  It seems like when the pixel type is
>>>changed, the raster data will need to be processed and either
>>>truncated or re-allocated, as the pixel type is changed.  Is that
>>>correct?
>>
>>>A also noticed that ST_SetWidth and ST_SetHeight are not in the spec,
>>>is that intentional?  Would it ever make sense to set the height and
>>>the width?  In one sense, ST_SetPixelType is performing the same kind
>>>of truncation/expansion on the bit depth as ST_SetWidth/ST_SetHeight
>>>would perform the truncation/expansion in the spatial dimension.
>>>Should ST_SetPixelType be dropped if ST_SetWidth and ST_SetHeight are
>>>not implemented?  Or should ST_SetHeight and ST_SetWidth be
>>>implemented as well?
>>
>> I agree that ST_SetPixelType does not really make sence... If I want to change the pixel type I would probably instead want to do something like:
>>
>> ST_MapAlgebra(raster, 'int(A)') on a float raster or ST_MapAlgebra(raster, 'float(A)') on a integer raster...
>>
>> Pierre
>> _______________________________________________
>> postgis-devel mailing list
>> postgis-devel at postgis.refractions.net
>> http://postgis.refractions.net/mailman/listinfo/postgis-devel
>>
>