Terahertz image enhancing based on the physical model and multiscale retinex algorithm

To settle the terahertz (THz) image degradation problem, we propose an effective enhancement method based on the physical model and multiscale retinex (MSR) algorithm. The overall enhancing process involves two parts: reconstruction and enhancement. First, the original THz images are reconstructed by a mathematical model, which is built and considered the THz absorption variate and Gaussian distribution of the beam. Then, the original images are processed by the proposed algorithm, which combines the atmospheric scattering model and optimized MSR algorithm. The proposed algorithm not only recovers the image scene radiance and removes haze, but also can make a compromise of the dynamic range of gray scale and edge enhancement of the image. Results on a variety of THz images demonstrate our method can effectively improve the quality of THz images and retain sufficient image details.