X-ray Image Enhancement Based on Wavelet Transform

Based on a combination of non-linear grad-contrast operator and multi-resolution wavelet analysis, a kind of image enhancement processing algorithm for useful tiny characters is presented. The algorithm can enhance the tiny characters while confine amplifying the noise. Low-contrast structure can be found in many kinds of digital images, which makes the images vague and uncertainly, especially in X-ray images. The analysis of the results shows that local regions of the image are enhanced by using the concept of the grad contrast to make image clearer adaptively. Experiments were conducted on real pictures, and the results show that the algorithm is flexible and convenient.