2008.06.19 19:05 "Re: [Tiff] Re: Conversion from CYMK Tiff to RGB Tiff", by Bob Friesenhahn

On Thu, 19 Jun 2008, Mitesh wrote:

>

> Is there a way to know if it is a CYMK Tiff file or an RGB Tiff file?

Yes. CYMK Tiffs use a planar configuration of "separated".

> Also, can we convert from CYMK Tiff to RGB Tiff through "libtiff"?

Not directly. I suggest taking a look at Little CMS ("lcms") at

http://www.littlecms.com/. There is a provided utility which supports

using CMS profiles with libtiff so you can use a profile describing

your variant of CMYK and use it to convert to a desired RGB.

Also, there are several image processing packages (e.g.

GraphicsMagick) which use lcms to do this work but with more power and

more convenient interfaces.

Here is tiffinfo output for a CMYK TIFF:

% tiffinfo crap.tiff
TIFF Directory at offset 0x5f4068 (6242408)
   Image Width: 1530 Image Length: 1020
   Resolution: 255, 255 pixels/inch

    Bits/Sample: 8
   Sample Format: unsigned integer

Compression Scheme: None
Photometric Interpretation: separated
Samples/Pixel: 4
Rows/Strip: 1

    Planar Configuration: single image plane

Page Number: 0-1
DocumentName: crap.tiff
Software: GraphicsMagick 1.3 unreleased Q16 http://www.GraphicsMagick.org/
Ink Set: CMYK
Photoshop Data: <present>, 6594 bytes
ICC Profile: <present>, 3144 bytes

Bob
======================================
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer, http://www.GraphicsMagick.org/