Perceptual image quality enhancement for solar radio image

In solar radio observation, the visualization of data is very important since it can more intuitively and clearly deliver interest information of solar radio activities to astronomers. As to visualization, we highly expect good visual quality of images/videos in favor of the discovery of solar radio events recorded by observation data. The existing imaging system cannot guarantee good visual quality of solar radio data visualization. In this paper, an image quality enhancement algorithm is developed to improve solar radio extreme ultraviolet (EUV) images from Solar Dynamics Observatory (SDO). Firstly, the guided filter is employed to smooth image, which outputs an image with good skeleton and edges. Since the fine structures of solar radio activities are embedded in high frequency components of a solar radio image, we propose a novel structure preserving filtering to amplify the different signal of original input image subtracting smoothed one. Afterwards, fusing the amplified details and smoothed one together, the final enhanced image is generated. The experimental results prove that the image quality is significantly improved by using the proposed image quality enhancement algorithm.