Abstract: A sub-screen generator used in displaying a single or a plurality of sub-screens concurrently with a main screen when reproducing video signals on TV.

Abstract: A system for identifying a seal stamp comprises a memory having stored therein two impression reference patterns, namely an original reference pattern and a latest reference pattern, for the seal stamp. An impression pattern read by a reader is collated with the latest reference pattern, and when the patterns are found to match, the read impression is verified and the latest reference pattern in the memory is updated with use of the read impression pattern. If the patterns are found not to match by the collation, the read impression pattern is collated by the original reference pattern. When the two patterns are found to match by this collation, the read impression is verified. The original reference pattern is updated when desired. The system is also useful for identifying other objects such as speech.