ST_Resize to resize raster tiles

[robe]

Bborie,

I'm ticketing what we discussed. As mentioned, it would be nice to have a resize function that provides the similar functionality to gdal_translate that can take a percentage reduction or max pixel dimensions.

e.g.

what gdal_translate:

gdal_translate -of png -outsize 25% 25% original.png final.png
gdal_translate -of png -outsize 500 500 original.png final.png

}

Currently have to use ST_Resample for this which requires a lot more arguments, not to mention it doesn't seem to work for rasters with no srid information.

I'm envisioning the signature would look something like


{{{
ST_Resize(rast raster, width text, height text)
}}}


where width can be a numeric like '500'  or can be a percentage like '50%' which is why I made it text.

This will make postgis raster useful for both GIS folks and non-GIS folks as having an easy function to resize a raster will speed up all kinds of analysis.  Like I mentioned, my selfish need is that most of my raster projects do not involve objects that fit in a nice spatial reference landscape but the analysis functions we've got so far I'm finding very useful for those (e.g. image recognition, and just plotting and vectorizing non-GIS like things like anatomic parts, or construction objects)