# Revision history [back]

### What exactly is Normalization of a matrix/image?

I was taking a look at the histogram equalizing function in this tutorial code ..> http://docs.opencv.org/doc/tutorials/imgproc/histograms/histogram_calculation/histogram_calculation.html#code

At the end of the program, they have used a function normalize( ). My question is, what does normalization do exactly? and what is it's specific purpose in this example?

### What exactly is Normalization of a matrix/image?

I was taking a look at the histogram equalizing calculation function in this tutorial code ..> http://docs.opencv.org/doc/tutorials/imgproc/histograms/histogram_calculation/histogram_calculation.html#code

At the end of the program, they have used a function normalize( ). My question is, what does normalization do exactly? and what is it's specific purpose in this example?