ITH: Improved TopHat for Smear Suppression in Astronomical Images

CCD-based detectors are widely used in astronomical observations, but non-instantaneous charge transfer can cause bright lines known as smear. This phenomenon affects both normal astronomical observations and subsequent image processing. Although TopHat-based methods can suppress most smears, they also distort the original distribution of bright sources. To address this issue, we propose a two-stage desmearing method. First, an improved TopHat (ITH) filter is designed for rough smear suppression. Then, a residue search and removal channel is employed to enhance visual performance. Experimental results on actual smeared images demonstrate that our method outperforms traditional approaches.