New image fusion method based on shift invariance shearlet transformation

The invention discloses a new image fusion method based on shift invariance shearlet transformation (SIST). The method includes the implementation steps of firstly, conducting multi-scale multi-direction decomposition on a source image through SIST to obtain low-frequency sub-band coefficients and high-frequency sub-band coefficients; secondly, reflecting the outline information of the image through low-frequency sub-bands, obtaining local structure descriptors for identifying the image resolution through a local structure tensor singular value decomposition method, making the local structure descriptors serve as movement measure functions in the fusion strategy, and adopting large strategy fusion. High-frequency sub-bands display detail information of the image. The invention provides a new edge strength measurement method, and a multi-strategy fusion rule based on the sigmoid function and edge strength measurement is made and used for high-frequency sub-band fusion. Finally, reverse SIST is conducted on the obtained fusion coefficients to obtain a final fusion image. The method overcomes the defect that edge distortion is easily caused by a traditional image fusion method, and more edge and detail information is reserved through the fused image.