A Study On Pixel-Level Image Fusion Technology

Image fusion is an integrated information processing technology, which mainly aims to improve the reliability of images by processing the redundant information and the definition of images by processing complementary information among several images. In recent years, image fusion has became into a new important and useful technology in the field of image analysis and computer vision. This paper is mainly to discuss pixel-level image fusion technology.After introducing the background of research, basic concepts, development, internal and external application and researches of image fusion technology, the paper elaborates the fundamental principles and methods employed in pixel-level image fusion technology and puts forth a combination of the subjective and objective evaluation criteria for image fusion performance and the effect of the fused images, which is proved to be reasonable and effective by a great number of experiments mentioned later in the paper.In the discussion of image fusion methods based on spatial domain, the paper introduces the simple image fusion method and then suggests, on the basis of fusion with weighted average, to figure out the weighted average coefficient by using PCA transform, which helps to form images of better fusion effect. And then describes the domainal properties-based method of which the overall performance is superior to that of simple fusion methods.The fourth chapter of the paper focuses on the wavelet-transform-based image fusion method of which the basic theories, multi-resolution analysis and Mallat fast arithmetic are discussed. Then the level-based and region-based fusion rules and implement of these are discussed and a novel fusion rule is raised. Through a series of experiments, what can be done to fusion performance by wavelet radix, the number of decomposition levels, different fusion of rules, the size of region for measure or threshold is studied according to valuation methods proposed in the paper.At the end of the paper, the paper brings forward a new fusion method on the basis of image segments. Experiments show that it can sustain useful information, realize the complementation of information and therefore have such advantages as simple arithmetic, fast runtime and better effect. Image fusion technology can be applied in many fields, and its application in medicine is also explored, which further support the methods advanced in the paper.