Pyramid-based image empirical mode decomposition for the fusion of multispectral and panchromatic images

Image fusion is a fundamental technique for integrating high-resolution panchromatic images and low-resolution multispectral (MS) images. Fused images may enhance image interpretation. Empirical mode decomposition (EMD) is an effective method of decomposing non-stationary signals into a set of intrinsic mode functions (IMFs). Hence, the characteristics of EMD may apply to image fusion techniques. This study proposes a novel image fusion method using a pyramid-based EMD. To improve computational time, the pyramid-based EMD extracts the IMF from the reduced layer. Next, EMD-based image fusion decomposes the panchromatic and MS images into IMFs. The high-frequency IMF of the MS image is subsequently replaced by the high-frequency IMF of the panchromatic image. Finally, the fused image is reconstructed from the mixed IMFs. Two experiments with different sensors were conducted to validate the fused results of the proposed method. The experimental results indicate that the proposed method is effective and promising regarding both visual effects and quantitative analysis.