"Provide ToZero Thresholding"
"img_ret"=cv_thresh_tozero("image","threshold","maxVal")
"Input Image it should be grayscale image if not it will convert it internally"
"It is the threshold value which is used to classify the pixel values. It should be Integer"
"It represents the value to be given if pixel value is more than (sometimes less than) the threshold value.It should be integer"
"Output image"
"ToZero Thresholding"
"ToZero Thresholding is a process where If pixel value is greater than a arbitrary value, it is assigned one value (may be white or black), else it is not changed"