Color Checker Chart

Synthesize a perfect version of the X-Rite Color Checker chart.

Description

The X-Rite Color Checker Chart is a very common standard used for standardizing different images and imaging systems. (This chart has been known in the past as the Gretag Macbeth ColorChecker Chart,
and the Munsell ColorChecker Chart.) You can take a photo of one chart and a different photo at a different time or on a different system, and then develop a transformation to match the two images based on the colors of the chart's chips.

This script makes (synthesizes) a perfect X-Rite Color Checker Chart from the X-Rite supplied sRGB values. (Note: This script just creates a nice perfect image (which you can save) so it can't be used for standardizing two different images or imaging systems. It's just for looks, for example to put in a publication.) You have options on the size of the image, whether you want informational text (chip name & color) in the overlay, and whether you want to save the image.

Acknowledgements

Export Fig inspired this file.

• Required Products: Image Processing Toolbox
• MATLAB release: MATLAB 8.0 (R2012b)
• Other requirements: export_fig() may be used to save the image, but it is not necessary. It will run without it. It will use saveas() if you don't have export_fig().

[Tim Zaman]

No, no, no, NO. You cannot state R,G,B values for such targets, "Image Analyst". The RGB colorspace is HIGHLY non-perceptually-uniform. Conversion to LAB would make it as perceptually uniform and standardized as you can get these days. And yes, you state that you use the sRGB values, but which sRGB whitepoint do you use? What observer degree? And so on. Convert your image to the appropriate LAB values and take the color space into consideration. Then compare LAB values.

[Malini]

 

[Malini]

I'm really impressed with your contribution . gr8. Thanks for sharing.