2005.12.23 22:01 "[Tiff] problem reading Photoshop CS2 JPEG-in-TIFF", by Dwight Kelly

2006.01.04 21:59 "Re: [Tiff] Re: Reading TIFF(CMYK)", by Kai-Uwe Behrmann

Am 04.01.06, 14:44 -0500 schrieb Dwight Kelly:

Arkadiusz Malka asked:

> it's possible to read only one color chanel from tiff(CMYK) let say cyan > and save it as greyscale?

All CMYK TIFF files should been PHOTOMETRIC_SEPARATED & SAMPLESPERPIXEL == 4.

I would not rely on the later. There are Cmyk images out with 1-bit, indexed 8-bit, 8-8-8-8 (as suggested in the spec) and 16-bit per sample, makes a variance of 4 to 64 bit per pixel. Sometimes colour planes are allready in separate files, which is what I expect will be the target of Arkadiusz.

Photoshop for instance writes 16-bit per sample Cmyk tiffs.

regards
Kai-Uwe Behrmann

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