Question on function graythresh

I want to use the function graythresh to find a global threshold of a gray scale image. The output level I know is normalized to be between 0 and 1. I want to know how is it normalized? I want to get back the actual intensity value I should use as a global threshold.

Also, does having lots of zeros in my image throw off graythresh?

Thanks

Answer 1

[Image Analyst]

You can multiply that 0-1 value by the max for the integer type:

maxValue = intmax('uint8') % or...
maxValue = intmax('uint16')

grayLevelThreshold = maxValue * grayThreshValue;