Defect detection from scratched 2-inch quadruplex video tape

A technique is described for the detection of defects in digital video images, caused by scratching to the original 2-inch quadruplex video tape. This technique relies upon the re-orientation of the digital video data into a manner similar to that in which the original analogue data would have been found on the video tape. This brings the scratched data into alignment and makes the task of detecting the scratched positions a great deal easier. The technique does not suffer from problems inherent in a previously described technique for addressing this problem (Harvey and Marshall 1997) and improves upon its performance.