Mosaic Defect Detection in Digital Video

The video quality can be degraded because of physical problems such as repeated projection, low-quality compression/decompression, or bad chemical decomposition of the original recording material. It becomes increasingly important to locate degraded video (video with defects) with the wide application of digital media. One common video defection is mosaic, where several even square combined together and the original image information is lost. In this paper, after analyzing the characteristic of the mosaic defect in detail, a mosaic defection detection approach in the spatial domain is proposed. Four even squares are detected firstly and the intersection points of these squares are selected as the features of mosaic macro block (MMB), and a mosaic consists of several MMBs. On the other hand, a fast and effective detection algorithm in the edge domain is proposed based on the analysis of existing approaches. Two tricks are adopted to speed up the detection: a new template matching strategy and the preprocessing of the edge image. Experiments are carried out and the results show that the proposed algorithms have good performance.