Low, Medium and High Contrast calculation

[alwittta]

Dear friends,

Anyone kindly tell me, using the class DicomImage, how can I calculate the low contrast, medium contrast and high contrast (WW/WL) for a CR DICOM image?

Following are the information about the CR image that I am using:

Bits Allocated – 16
Bits Stored - 10
High Bit - 9
Photmetric - MONOCHROME1
Sample per Pixel – 1

Using the function getMinMaxValues of DicomImage class, minimum and maximum pixel values from the CR file as follows:
Min = -240
Max = 2640

Please provide a solution
Thanks and Regards
Alvin

[Marco Eichelberg]

I don't think that there is any standard definition for "low, medium and high contrast". A low contrast window would probably cover the complete range of used pixel values (in your example width = 2640+240, center = (2640+240)/2-240). Medium and high contrast would define smaller window sizes based on whatever criterion. The histogram based windowing options in DicomImage might be a reasonable choice.

[alwittta]

Dear Marco

Thanks for the reply.
I am trying to figure out the calculation of medium and high contrast, but I don't get any solution.

Could you please provide here a criterion on the calculation of medium and high contrast using the class DicomImage?


Thanks and Regards
Alvin