Research Of Post-processing For Medical Image And The Application In X-ray Image Optimization

Modern Clinical Medicine needs the supporting by medical images. A hundred years since the discovery of X-ray by Wilhelm Conrad Rontgen,the medical image equipment is innovated continuously with the development of computer, automatization, electronic technique and other techniques. From 2-D X-ray image to 3-D CT reconstructed image, from CT and MRI which can reflect human anatomy and configuration to SPECT and PET which can reveal the organization or the function and metabolism of organs of human body. All the imaging modalities make the medical images and image information playing a more and more important role in the field of clinical diagnosis and medicine research. The object of the medical image post-processing technique is how to make full use of the image information to improve the diagnostic efficiency and quality. The research on medical image post-processing began from the evening of 70 years. With the development of the image equipment, the research of this field has been changing and improving. As a result of the development of computer science, CT, PET, MRI, especially the multi-media technique and Internet progress, of late years, the requirement is upsurging and going deeply. Now the medical image post-processing includes image enhancement, image segmentation, image registration and fusion, image compression and image visualization, ect. The first task of the medical image post-processing is image enhancement, that is to enhance the Signal-to-Noise ratio, filtrate the noise, stand out the range of interests or edge and to lay a foundation for analysis and calculation. Contrast enhancement, smoothing, sharpening, pseudo-color processing are the methods in common. Image segmentation is absolutely necessary step for object separating, quantitative analyzing, 3-D reconstructing and image fusion, and so on. The methods used widely are threshold value segmentation, edge detection and region-based segmentation. Image registration and fusion developed in recent years. The medical image having been fused possesses the information from different physiology, pathology and anatomy, which are very valuable for clinical diagnosis. Image visualization can express the information of human body getting by CT, MRI into 3-D form, and remedy the shortcoming of imaging equipment. The technology plays an important role in diagnosis, surgery emulating and inducting treatment. Image compression is one of the key technologies for remote diagnosis and PACS. Its main goal is to decrease the storage room, reduce network transmission burden, improve the compressed image quality and looking for the high efficient compression code. At present, in various medical images, the different kinds of X-ray images are widely used in clinical diagnosis. But influenced by the complexity of body tissues and some factors such as X-ray scatter and noise, the X-ray images display as the specialties of wide gray scale, high-degree overlap, high noises, large numbers of datum and low contrast. How to develop the applicable medical image post-processing system according the features of X-ray to extract the useful information, is the key point to improve the clinical diagnosis level. From the point of application, this paper takes the living example of X-ray images used widely in most hospital, makes deep research on the base of the analysis and application of theory and technology of image enhancement, image segmentation and image registration and fusion, and develops the medical image post-processing system tentatively. The research combines medical image informatics with digital image processing, and the main studies as follow: 1. The basic conception and the application study of medical image post-processing; 2. Analyzing the factors of X-ray medical image based on the research of X-ray imaging equipment and theory; 3. In-depth research on the basic theory and the correlative algorithms...