Enhancement of radiography based multiscale Retinex

An enhancement algorithm of radiography based on multiscale Retinex was presented.The three different Gaussian filter coefficients under three different deviations were calculated,and the convolution operation was implemented between the image distribution and Gaussian filters,a weighted average of multiscale was gained and mapped to gray range of display device.With this method,image contrast enhancement,sharpening and dynamic range compression were achieved at the same time.The information of hidden area of digital radiograph was obviously enhanced.The enhancement technique was compared with other techniques such as histogram equalization,homomorphic filter.The results of experiment show that MSR can more observably improve entropy of digital X-rays than other techniques,and also show that the algorithm can overcome the lack of enhancement of traditional digital X-rays methods and satisfy the clinic demand.