*Article* **An Adaptive Denoising and Detection Approach for Underwater Sonar Image**

**Xingmei Wang 1,\*, Qiming Li 1, Jingwei Yin 2,3,4, Xiao Han 2,3,4 and Wenqian Hao <sup>5</sup>**


Received: 14 January 2019; Accepted: 12 February 2019; Published: 15 February 2019

**Abstract:** An adaptive approach is proposed to denoise and detect the underwater sonar image in this paper. Firstly, to improve the denoising performance of non-local spatial information in the underwater sonar image, an adaptive non-local spatial information denoising method based on the golden ratio is proposed. Then, a new adaptive cultural algorithm (NACA) is proposed to accurately and quickly complete the underwater sonar image detection in this paper. Concretely, NACA has two improvements. In the first place, to obtain better initial clustering centres, an adaptive initialization algorithm based on data field (AIA-DF) is proposed in this paper. Secondly, in the belief space of NACA, a new update strategy is adopted to update cultural individuals in terms of the quantum-inspired shuffled frog leaping algorithm (QSFLA). The experimental results show that the proposed denoising method in this paper can effectively remove relatively large and small filtering degree parameters and improve the denoising performance to some extent. Compared with other comparison algorithms, the proposed NACA can converge to the global optimal solution within small epochs and accurately complete the object detection, having better effectiveness and adaptability.

**Keywords:** underwater sonar image; adaptive denoising; detection; adaptive initialization
