Infrared image enhancement is a crucial technique for improving the quality of infrared images. And, the

clear image details are important information for infrared image analysis. To effectively enhance infrared

image and make image details clear, a multi-scale sequential toggle operator based algorithm is proposed

in this paper. Firstly, the sequential toggle operator, which uses opening and closing as primitives, is con-

structed and discussed. Secondly, the feature extraction in infrared image through the sequential toggle

operator is given, and the multi-scale extension of the feature extraction is discussed in details. Finally,

the extracted final