2006.01.04 21:57 "Re: [Tiff] Re: Reading TIFF(CMYK)", by Dwight Kelly

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.

Hello, I'd be happy to write a C routine with a demo application for you to split CMYK TIFF (all types) into 4 grayscale TIFF. It shouldn't take more than a couple of hours.

Sincerely,
--

Dwight Kelly
Apago, Inc. 4080 McGinnis Ferry Rd Suite 601 Alpharetta, GA 30005
voice:(770) 619-1884 fax:(770) 619-1885
email: dkelly@apago.com web: http://www.apago.com