Non-maximum suppression is used in CV in object detection where multiple probabilities that are above the given threshold are detected(classification result).
Thus non-maximum suppression can help to suppress all the gradient values (by setting them to 0) except the local maxima classification result.
If the strength of the current pixel/elemnt is the largest compared to the other pixels/elements classified it will be picked as the output object and all the rest of the neighboring pixels/elements that where detected that have an IOU with the current pixel will be suppressed.
