MATLAB: CIELAB values from TIFF image

cielab tiff image color space

hello,

I'm trying to read CIELAB values from TIFF image in Matlab with:

A_lab= imread ('A', 'tiff');

what I get is A_lab<1x33x3 unit8> with values [0,255] which are not CIELAB values that I want (positive & negative integer and non-integer).

Have any idea?

thanks

Best Answer

http://www.mathworks.com/help/techdoc/ref/imread.html says,

"If a file contains CIELAB color data, imread converts it to ICCLAB before bringing it into the MATLAB workspace because 8- or 16-bit TIFF CIELAB-encoded values use a mixture of signed and unsigned data types that cannot be represented as a single MATLAB array."

See http://www.mathworks.com/help/techdoc/ref/imwrite.html for a description of ICCLAB encoding

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