An auto-focusing noise suppressor for cellphone movies based on peak preservation and phase randomization

This paper proposes an auto-focusing noise suppressor (AF-NS) for cellphone movies. For relatively small clicks compared to the target signal, it consists of magnitude suppression and complementary phase modification. The input signal is analyzed in the frequency domain to detect and preserve important spectral components including peaks and their vicinities. All other components are suppressed to the environmental signal level that is estimated during absence of the important components. Residual spikes by auto-focusing noise are successfully suppressed by phase randomization. Subjective evaluation results demonstrate that the proposed AF-NS achieves scores of 1.6 and 1.8 in the 7-grade modified CMOS with statistically significant differences compared to the input noisy signal and an AF-NS with no phase randomization.