Abstract: In order to display dual X-ray images with high dynamic range from a security inspection system without losing details， a self-adaptive tone mapping algorithm based on the multiscale local edge-preserving filter was proposed. The input image was decomposed into one base layer and three detail layers by using the LEP filter. An adaptive logarithmic transformation was carried out in the base layer to compress the dynamic range and the three detail layers were enhanced by an adaptive Sigmoid function. Every detail layer image was fused with the base layer image and histogram equalization was taken considering noise and increasing contrast. The proposed algorithm was used to dispose the high and low energy X-ray images at the same time and both of them were combined according to their own merits， which could get a low dynamic range dual X-ray image with rich details. Experimental results showed that the proposed algorithm highly improves images information entropy， contrast improvement index and peak signal to noise ratio， which indicates that the image quality is successfully optimized.

Key words: dual X-ray; security inspection image; high dynamic range; self-adaptation; multiscale filter; fusion image