<title>Optimized algorithm for adaptive histogram equalization</title>

Adaptive histogram equalization (AHE) is a useful technique for expanding local contrast in medical images. The method is based on histogram equalization of each pixel based on a local NXN image region. If the number of pixels in the NXN local region is equal to the number of grayshades in the image, the equalized histogram can be directly constructed from the distribution histogram. This optimization may permit AHE to be performed on standard medical image display workstations.