Image fusion algorithms using discrete cosine transform

Abstract

An image fusion algorithm based on discrete cosine transform(DCT) and an image fusion scheme using wavelet transform combined with DCT were proposed.The former based on DCT fused the corresponding areas of the original images according to the DCT coefficient high frequency energy and the latter using wavelet transform and DCT fused the low frequency submaps by use of DCT coefficient high frequency energy.The wavelet high frequency coefficients of the highest wavelet decomposition level were decided by the wavelet low frequency coefficients.The wavelet high frequency coefficients of the other wavelet decomposition levels were selected with the greater local deviation.The fused images of the algorithms purposed were evaluated by some parameters such as average error,peak signal noise rate,and root mean square error,compared with other conventional image fusion methods based on wavelet transform or DCT.The experimental results show that the new algorithm based on wavelet transform combined with DCT provides the best performance with 40.8% to 69.5% reduction in average error,9.9% to 15.6% improvement of peak signal noise rate and 34.8% to(47.5%) reduction in root mean square error.It is superior to the conventional methods using wavelet transform.This algorithm improves the quality of the fused image effectively,the evaluation results coincide with the visual effect very well.The algorithm based on DCT needs less computational burden and is more suitable for the real-time processing.