OpenCV, To create Histogram and Draw example source code

Example source code to make histogram and drawing.
Show the 'mareHistogram' function.
Input is Mat. The property is CV_8U and binary image.
Output is also Mat. The output Mat is image of histogram.
If you want to get histogram value array, you should get mhist Mat instead of histo in the function.

Thank you.

histogram, countNonZero, vertical, horizontal