Video recordings of meetings and scanned paper documents are natural
digital documents that come out of a meeting. These can be placed on the
Internet for easy access, with links generated between them by matching
scanned documents to a segment of the video referencing the scanned
document. Furthermore, annotations made on the paper documents during the
meeting can be extracted and used as indexes to the video. An orthonormal
transform, such as a Digital Cosine Transform (DCT) is used to compare
scanned documents to video frames.