一种基于 DCT 域局部能量的多聚焦图像融合算法

摘要

为了在无线视觉传感器网络等资源受限的应用中实现图像信息融合，提出一种基于离散余弦变换域 DCT（Discrete Co-sine Transform）中局部能量的多聚焦图像融合算法。该算法没有采用当前常用的基于对比度和方差的融合准则，而是通过计算图像在 DCT 域的局部能量，选择局部能量较大的分块实现融合。实验结果表明，该算法能获得良好的主观视觉融合效果，且在互信息、峰值信噪比和空间频率等客观指标上优于常用的基于小波变换的融合算法，计算量与基于 DCT 域方差的融合算法相比降低约41％～49％，该算法适用于诸如无线视觉传感器网络等资源受限或实时性要求高的应用场合。%In order to apply image information fusion to resource-constrained applications such as wireless visual sensor networks,we presented a multi-focus image fusion algorithm,which is based on local energy in discrete cosine transform (DCT)domain.The proposed algorithm doesn’t employ commonly used rule of image fusion based on contrast and variance,but realises fusion by calculating the local energy of image in DCT domain and selecting the blocks with bigger local energy.Experimental results showed that the proposed algorithm could get good subjective visual effect of fusion,and outperformed those usual algorithms based on discrete wavelet transform in objective evaluation indexes such as mutual information,peak signal to noise ratio,space frequency and so on.Moreover,since the calculation decreases by around 41 percent to 49 percent in comparison with the fusion algorithm based on variance in DCT domain,the presented algorithm is suitable for the applications with resource-constrained or high real-time property like visual sensor networks.