Bad design or lack of good API of JavaCV

Why the design of the JavaCV API is not as convenient as the user can use the APIs easily. For example the following APIs no available:

Scalar(255, 255, 255) // no constructor for three value
add(Mat mat, Scalar scalar, Mat mask) // not convinent add method a mat and a scalar
mat.setTo(new Scalar()); // not such method to set all the value to the given scalar
mat.get(x, y, data[]); // get data 
mat.put(x, y, data[]); // put data

I think there are a lot of things need to redesign, improve ...etc. I have tested the converters which have written by me and written by JavaCV, the speed of one which was written by me was much faster than the JavaCV. So it seems that there are things needs deeply care of.

And also The are a lot of deprecated objects still present in the API, it makes the users very very headache, it is good the API to be cleared from the deprecated code. And also the are no good classified of modules, classes, ...