导航

Acta Aeronautica et Astronautica Sinica ›› 2024, Vol. 45 ›› Issue (10): 329162-329162.doi: 10.7527/S1000-6893.2023.29162

• Electronics and Electrical Engineering and Control • Previous Articles     Next Articles

Optical⁃SAR image matching based on MatchNet and multi⁃point matching constraint

Yibin YE, Xichao TENG, Qifeng YU, Zhang LI()   

  1. College of Aerospace Science and Engineering,National University of Defence Technology,Changsha 410073,China
  • Received:2023-06-13 Revised:2023-07-17 Accepted:2023-08-11 Online:2024-05-25 Published:2023-09-01
  • Contact: Zhang LI E-mail:zhangli_nudt@163.com
  • Supported by:
    National Natural Science Foundation of China(61801491)

Abstract:

Multimodal image matching between optical and SAR images is critical for visual navigation of the aircraft flying over complex areas. Due to different imaging mechanisms, accurate optical-SAR image matching faces several challenges, such as imaging geometry differences between optical and SAR, nonlinear radiation distortion of SAR, and noise interference. Although deep learning-based image matching methods have shown better adaptability than traditional methods, they still cannot fully solve the above-mentioned challenges and their matching accuracy may be not enough for visual navigation tasks. This paper proposes a new image matching method called Multi-point Matching Constraint MatchNet (MMC-MatchNet) based on the typical MatchNet framework, so as to improve the matching accuracy of the single template matching using MatchNet. The method consists of two main steps: sub-templates sampling and matching using MatchNet, and mismatched sub-templates removal based on multi-point geometric constraint. The original input image size of the MatchNet is maintained, while the matching accuracy for optical-SAR image matching is improved. This paper also proposes a multi-level training dataset generation method to train the MMC-MatchNet. Compared to the random sampling method, our method focuses on the difficult samples in image matching, and can be seen as a special data augmentation method for image matching. MMC-MatchNet is tested on two multi-modal image matching datasets, outperforming NCC, NMI, HOPC and the single-template MatchNet. With similar matching accuracy to that of HOPC, MMC-MatchNet can improve the Correctly Matching Rate (CMR). The method based on multi-point matching constraint and multi-level dataset generation can be easily extend to other patch-based image matching models.

Key words: image matching, template matching, optical image, SAR image, MatchNet

CLC Number: