Performance Evaluation of Image Fusion Based on Discrete Cosine Transform

Discrete cosine transform (DCT) is used for fusion of two different images and for image compression. Image fusion deals with creating an image by combining portions from other images to obtain an image in which all of the objects are in focus. Two multi focus images are used for image fusion. Different fusion algorithms are used and their performance is evaluated using evaluation metrics such as PSNR, SSIM, Spatial Frequency, Quality Index, Structural Content, Mean Absolute Error. Fusion performance is not good while using the algorithms with block size less than 64x64 and also the block size of 512x512. Contrast, amplitude and energy based image fusion algorithms performed well. The fused images are comparable with the reference image. Only the image size is considered but blurring percentage is not considered. These algorithms are very simple and might be suitable for real time applications.