Algorithm of image enhancement based on order morphology filtering and image entropy difference

According to correlative conception and properties of order morphology transformation, a non-linear weighted mean value filter is constructed to remove high frequence noise such Gaussian and impulse noise. Then an approximated midpoint value filter, which can reject uniform distribution noise is given by improving the weighted mean value filter. Based on the above, a new image enhancement algorithm is proposed. In this algorithm, weighted mean value of the image about structuring elements of different directions is calculated and used to identify the edge of the image; local average value and image entropy difference is applied to control enhancement coefficients. So the target and edge of the image are elevated while high frequency noise of the image is restrained. A comparison of average value, standard deviation and image entropy between the enhanced image and its original illustrates that contrast of the image is also improved.