The Study Of Medical Image Enhancement Based On Dyadic Wavelet Theory

In recent years, with the practical application of the wavelet analysis theory field is more and more widely, and you can more and more of attention. Especially for medical image processing, due to the limitation of actual medical level and the body and the external environment condition, such as temperature, light, makes the medical images obtained in the process of medical tend to have different levels of noise pollution. This if before the doctor in clinical diagnosis of medical image enhancement processing, improve the original details, the fuzzy definition, the quality of the low contrast image, can effectively reduce the probability of misdiagnosis, thus greatly improve the accuracy of medical diagnosis.Wavelet image analysis, as a new type of effective image analysis and processing technology, play an important role in medical image enhancement. The biorthogonal wavelet and dyadic wavelet is most widely applied in medical image. Because of the dyadic wavelet transform for image doesn’t do the sampling process, its itself have a combination of translational invariance, therefore, after processing precision of image shows excellent features; But biorthogonal wavelet transform doesn’t have translation invariance, and sampling, leading to the processed image precision less than dyadic wavelet transform. Therefore, this article embarks from the Mallat proposed Sweldens lifting scheme, raises the dyadic lifting scheme of T.Abdukirim proposed, and respectively using T.Abdukirim(r=2) and Mallat(r=1) structure of spline dyadic wavelet filter for initial wavelet filter, dyadic lifting and dual lifting scheme, get new higher order moment of dyadic wavelet filter.Throughout the existing medical image enhancement method, based on dyadic wavelet theory research isn’t deep enough, this article based on the inherent enhancement method. Through a large number of Matlab experiment, compared to improve ago after initial dyadic wavelet filter and promote new disappear of higher order moment of dyadic wavelet filter on the effectiveness of medical image enhancement performance, prove improved dyadic wavelet filter has the certain progress than the initial dyadic wavelet filter, it is superior to direct use the initial dyadic wavelet filter of medical image processing, is an effective enhancement method of medical image.