[GRASS-dev] Re: [grass-code I][329] r.out.gdal: COMPRESS=JPEG yields "ERROR 1: JPEGSetupEncode:PhotometricInterpretation 3 not allowed for JPEG"

[Glynn Clements]

Maciej Sieczka wrote:

> >> r.out.gdal creates paletted images (i.e. the map data is saved as a
> >> single band; it isn't expanded to RGB).
> >>
> >> Note that the argument to creatopt= is passed directly to GDAL. 
> >> r.out.gdal has no knowledge of which options are allowed or
> >> meaningful, so it's up to the user not to pass options which won't work.
> 
> I guess I comply.
> 
> In spearfish:
> 
> $ g.region rast=vegcover
> $ r.out.gdal in=vegcover format=GTiff type=Byte
> out=tmp/vegcover_jpg.tif createopt=COMPRESS=JPEG
> 
> 
> Is there something wrong with: "format=GTiff type=Byte
> createopt=COMPRESS=JPEG" when exporting an integer raster, value range 1-6:

Yes; the use of createopt=COMPRESS=JPEG.

> In spearfish:
> 
> $ r.info -t vegcover
> datatype=CELL
> 
> $ r.info -r vegcover
> min=1
> max=6
> 
> in the context of what GDAL's GeoTIFF spec says: "JPEG should only be
> used with Byte data"?
> 
> [1]http://www.gdal.org/frmt_gtiff.html

r.out.gdal creates paletted images, to which JPEG compression cannot
be applied.

IOW, regardless of which other options you use,
createopt=COMPRESS=JPEG will always result in an error.

-- 
Glynn Clements <glynn at gclements.plus.com>