An OWE-based Algorithm for Line Scratches Restoration in Old Movies

Line scratch is the primary artifact in old films. In this paper a new algorithm for line scratch detection and removal is proposed. First, we establish an effective model to represent line scratches in the domain of over-complete wavelet expansion (OWE), which offers more precise position description for scratches than traditional downsampled wavelet transform. We then use it to detect and locate line scratches accurately. After that, an adaptive restoration method is adopted to remove line scratches by replacing the wavelet coefficients in line scratches of each scale with new interpolated wavelet coefficients of corresponding width computed from the line scratch model. Experiments show that the proposed method can detect more line artifacts with less false detection and remove the line scratches effectively as compared with the classic algorithm.