In recent years, there has been a growing interest in the old archived videos owing to having significant cultural and historical records. Most of the old archive-management organizations do not consider the quality of videos, rather aim only to archi...
In recent years, there has been a growing interest in the old archived videos owing to having significant cultural and historical records. Most of the old archive-management organizations do not consider the quality of videos, rather aim only to archive the videos in large numbers. Contrariwise, the recent advancement in the amenity of digital videos including the wider screen, better resolution, and screen-contrast has made the users habituated with experiencing better-quality videos. Hence, to address this issue, most archive-management organizations convert the old digital/analog media into a new digital file before archiving. This digitization process may introduce new errors in the file and/or inherit the errors in the original analog tape, causing degradation to the quality of the video. Existing efforts have tried to tackle this issue through human visual inspection, which at times suffers from efficiency due to the large number of video contents. To overcome such limitations of human visual inspection, automated quality control (QC) has been proposed in the literature, which also shows its shortcomings in error detection, error recovery, and system implementation processes. More specifically, the error-detection process may suffer from either high false discovery rate(FDR), or inability to capture errors at the same position for consecutive frames having a different format. The error recovery process undergoes with blurred-boundary in some videos having large motion variations. Moreover, most existing systems are not designed to address each possible error, and most importantly, they do not support real-time inspection of large video archives.
To solve these problems, this work aims at designing an automatic video-error detection and restoration system, broadly covering three major sections including error-detection, error-recovery, and system implementation. In particular, we perform digital dropout detection through introducing a discriminant DCT coefficient-driven block descriptor. We also propose a blotch-detection algorithm based on five-frame extended Rank Order Detector(ROD) to detect the errors occurring in the same position of consecutive frames. In the case of error-recovery, we propose a method that measures the reliability of each pixel in the error frame followed by reconstructing it from the surrounding pixels on the space-time domain by considering motion estimation. Besides, we propose a method for restoring color degradation, using inverse transformation process by formulating a color degradation model, based on degraded color bar as polynomials. Finally, we offer an inspection system that integrates the video above mentioned error detection/restoration techniques. We also propose a cloud-based system for automatic synchronization of error detection and error recovery systems, which is especially useful for large-capacity video archiving.
This system is commercialized as a product called Hawkeye that supports the detection of more than twenty errors. However, in this dissertation, we deal with some specific errors that occur highly in most archived media. The proposed system has proven its performance in the real broadcasting station and archive environments.