[Gdal-dev] GTiff / gdal_translate / CMYK - problem

[Frank Warmerdam]

Maksim Sestic wrote:
> Hi all,
> 
> I'm having troubles with gdal_translate while creating uncompressed 3-band
> GTiff with CMYK photometric representation. Well, at least CMYK
> representation recognized by Photoshop, which is
> PhotometricInterpretation=5. If I use recommended gdal_translate -co
> 'PHOTOMETRIC=CMYK' switch I keep getting "grayscale" (!) result, again,
> that's what Photoshop says (PhotometricInterpretation=1).
> 
> What other -co parameters should I set to make it work? I'm using
> gdal_translate from FWTools 2.2.3 
> 
> 
> Here's the gdalinfo reports:
> 
> 1) For RGB raster parsed with gdal_translate -co 'PHOTOMETRIC=CMYK'
>  switch:
> 
> Size is 945, 945
> Coordinate System is `'
> Metadata:
>   AREA_OR_POINT=Area
>   TIFFTAG_SOFTWARE=MyApp
>   TIFFTAG_DATETIME=20.08.2008 02:51:37
>   TIFFTAG_XRESOLUTION=240
>   TIFFTAG_YRESOLUTION=240
>   TIFFTAG_RESOLUTIONUNIT=2 (pixels/inch)
> Image Structure Metadata:
>   INTERLEAVE=PIXEL
> Corner Coordinates:
> Upper Left  (    0.0,    0.0)
> Lower Left  (    0.0,  945.0)
> Upper Right (  945.0,    0.0)
> Lower Right (  945.0,  945.0)
> Center      (  472.5,  472.5)
> Band 1 Block=945x2 Type=Byte, ColorInterp=Gray
> Band 2 Block=945x2 Type=Byte, ColorInterp=Undefined
> Band 3 Block=945x2 Type=Byte, ColorInterp=Undefined
> 
> Side note: I also tried using -co 'PHOTOMETRIC=YCBCR' and
> 'PHOTOMETRIC=CIELAB'switches but then gdal_translate crashes.

Maksim,

I would note that CMYK photometric interpretation requires 4 bands.
Furthermore, GDAL does *not* manage the conversion to CMYK color space.
You would need to do that ahead of time by some means.

I've never tried to create CMYK files so I don't have any further advice.

Best regards,


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