Frequency domain correction method for pneumatic thermal radiation effect

Abstract

The invention discloses a frequency domain correction method for the pneumatic thermal radiation effect. The method comprises the steps that approximation of thermal radiation noise is performed through a Gaussian curve, Fourier transform is performed and an amplitude spectrum is obtained, then normalization and segmentation are performed on the amplitude spectrum to acquire a filter binary template BW, and a filter function H is constructed through the acquired filter binary template BW; and Fourier transform is performed on a pneumatic thermal radiation degeneration image f to obtain a centralized frequency spectrum F, the F and H points are multiplied and then a filtered real-time image frequency spectrum G is obtained, and finally inverse Fourier transform is performed on G and modular operation is performed so that an image g after thermal radiation correction is obtained. With application of the method, background noise generated by pneumatic thermal radiation can be effectively removed and a clear image can be recovered so that the image quality and the image signal-to-noise ratio can be greatly enhanced. Besides, algorithm complexity is further reduced and operation time is reduced, and thus the method is more suitable for real-time processing.

Description

technical field [0001] The invention belongs to the field of interdisciplinary science and technology combining aerospace technology and image processing, and more specifically relates to a frequency-domain correction method for aerodynamic thermal radiation effects. Background technique [0002] Hypersonic vehicles have become an important development direction of the world's aerospace technology, and will have extremely high strategic significance in the political, military and economic fields. The high-speed flight of the aircraft leads to a series of aero-optical effect problems such as the deterioration of the image quality of the imaging sensor and the significant decrease in the signal-to-noise ratio, which hinder the development of hypersonic aircraft and need to be resolved. [0003] The aerothermal radiation effect usually refers to the complex flow field formed by the interaction between the optical window and the incoming flow when a high-speed aircraft with an o...

AI Technical Summary

Problems solved by technology

The high-temperature airflow will continuously transfer heat to the low-temperature wall surface, causing strong aerodynamic heating, which will cause radiation interference to the imager, increase the background brightness of the infrared image, degrade the quality of infrared imaging, and seriously affect the navigation, positioning and detection capabilities of hypersonic vehicles

[0004] At present, there are related literatures or patents to report the correction method of aerothermal radiation effect, but these methods all have the problems of complex calculation, time-consuming or only provide a modeling method, etc.

are not suitable for real-time processing, therefore, a new correction method for real-time processing is urgently needed in this field

Images