Enhancement of images is applied over all the mammographic images before their diagnosis. The contrast of mammograms is always required to be good so that further investigation of breast cancer images is accurate. Here HE (histogram equalization), HS (histogram specification) and LE (local enhancement) methods are discussed for enhancing and improving the quality of mammographic images and their result and performance are compared with statistical parameter SNR (signal to noise ratio) and RMSE (root mean square error). In histogram techniques, the flexibility of this image processing approach is emphasized to enhance the images. The experimental result indicates that the algorithm can not only enhance image information effectively but also keep the original image luminance well enough fine structure of the image.

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Contrast Enhancement Mammographic Images Histogram Snr (signal To Noise Ratio)