Author(s): Ashok Kumar Meena, Kalpana Rai

In the environment various type of noise is found which degrades the quality of images. To get the better quality of image or information a process is used which is called image fusion. This process fuses/ combines two or more image of same kind which produces the resultant image of better quality than the input image. Fusion process extremely utilizes more completely and superfluous information. Images counterfeit sometimes during accomplishment or transmission or due to error in memory locations in the hardware. Image fusion can be done at different levels such as pixel level, feature level and decision level. The image fusion techniques are classified into two category spatial domain and frequency domain techniques. In this paper, present literature study about the earlier work done in the field of image fusion to get better quality of image. We also describe the various image fusion techniques with their merits and demerits. Keywords: Image Fusion, Spatial Domain, Frequency Domain, Noise