In order to comprehensively and objectively study the degenerate factors of underwater turbulent imaging and optimize the corresponding image restoration algorithms, a reusable submarine imaging experiment system with a controllable turbulent flow condition is established. The circulating water pump is used to control the intensity of turbulence in the laboratory tank.The bubble generator is used to generate micro bubbles. The image sensor is used to obtain the images of sinusoidal stripe target plates under different conditions. The effect of turbulent flow field, path radiation and fluid media on submarine imaging in turbulent flow were studied, and the differences and applicability of modulation transfer functions (MTFs) of three degradation factors are compared by combining image restoration and super-resolution reconstruction. The experimental results show that the turbulent flow field causes MTF declines of the low spatial frequency, and the path radiation and fluid media lead to the decrease of modulation contrast of the high spatial frequency. In the restoration of the underwater turbulent degraded image, the MTF of the turbulent flow field is suitable for image restoration, and the MTFs of the path radiation and fluid media are suitable for image reconstruction.
Degradation and optimal recovery of underwater turbulent imaging
First published at:Dec 01, 2018
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Supported by Research Project of Hubei Provincial Department of Education in China (Q20171010)
Get Citation: Chen Yuzhang, Ye Ting, Cheng Chaojie, et al. Degradation and optimal recovery of underwater turbulent imaging[J]. Opto-Electronic Engineering, 2018, 45(12): 180233.