Research on Algorithm of Digital Filtering Based on Video Information Security

In this paper, on the basis of the spot pulse width corresponded with character video information vertical stroke, the safe bandwidth of video information is confirmed, filtering image quality appraisal model which takes difference threshold limit value as distinction parameter is built by Weber - Fechner law, the corresponding relation of filtering stop-band cut-off frequency and character is determined, the FIR digital filter is designed. In addition, aim at the periodic variation characteristic of the insertion loss which the digital filter inherent, a combinatorial filtering method combine digital filter and analog filter is presented. At last, the correctness and effectiveness of theoretical analysis are validated through simulations and experiments.