关键词: 高动态红外图像, 细节增强, 去噪, 导向滤波, 参数优化

Abstract: Focusing on the noise amplification, insufficient enhancement of small details and excessive enhancement of edge in the process of high dynamic range infrared image compression and detail enhancement, a novel detail enhancement and denoising method based on double guided image filtering is proposed in the present study. We first applied GIF to obtain two groups of base images and detail images. The base image with low ε is used as an estimate of denoised base component and correspondingly the detail image as the noise estimation. Thus, the difference between the two detail images can be logically used to estimate the denoised detail. After the two estimated components are processed and compressed into the display range by our modified automatic gain control method respectively, we recombine the two parts and obtain the enhanced and denoised image. An optimization model based on classification statistics of gray value convergency in detail pixels is also presented, which provides reasonable numerical range of the critical parameter ε in GIF. The experimental evaluation shows that the algorithm can accurately choose key parameters and improve the slight details and enhance edges while highlighting details and reducing noises. Furthermore, our proposed method is characteristic of being real-time, requiring simpler models and fewer parameters.

Key words: high dynamic range infrared image, detail enhancement, noise reduction, guided image filtering, parameter optimization