Infrared image enhancement algorithm based on IWGIF and WTD

Aiming at the problems of detail loss, edge blurring and noise amplification in traditional infrared image enhancement methods, an algorithm based on improved weighted guided image filtering (IWGIF) and wavelet thresholding denoising (WTD) is proposed. The algorithm first uses IWGIF to filter and layer the input image to obtain the base layer and detail layer. For the base layer, the high-frequency component obtained through wavelet decomposition (WD) is processed through WTD and subsequently reconstructed using wavelet reconstruction (WR) along with the low-frequency component. Contrast is then enhanced by contrast limited adaptive histogram equalization (CLAHE). For the detail layer, its edge details are enhanced by gain calculation. Finally, the processed two layers are weighted and fused to obtain the enhanced image. In this paper, the algorithm is applied to images captured by infrared thermal imaging devices, and the results of the combination of subjective and objective evaluation indexes show that the method in this paper shows good performance in infrared image enhancement.