Contrast measurement for MRI images using histogram of second-order derivatives

The proposed method is a contrast measurement technique which makes use of the second-order derivatives of the pixels in MRI images. The technique utilizes the changes in the histogram of second-order derivatives for the image, specifically the region under a Laplacian curve which approximates the distribution of the pixel frequencies in the histogram. As gain is introduced, the region of the histogram under the curve changes. The standard deviation of the frequency differences between the histogram and the curve in the region is used as a measurement score. The objective of this method is to provide a way to include small details, such as small blood vessels, in the contrast measurement, compared to local average contrast and RMS contrast measurements which do not. The outcome is a scoring method which not only provides a measurement of contrast, but also indicates the loss of small details in MRI images.