Matsushita Electric Industrial Co., Ltd.

Tomohiro Okuno

Norihiko Mizobata

Kazuhisa Tanaka

Wakahiko Okazaki

Yasuhiko Tomikawa

The present invention provides an on-screen display apparatus which can eliminate variations in the DC level at a time when an input chroma signal and an OSD chroma signal are switched, and prevent an erroneous display of color. The on-screen display apparatus of the present invention comprises a voltage holder which holds a voltage value at a time when the input chroma signal is a null signal, and an output switch which outputs the voltage value held by the voltage holder in an OSD period and outputs the input chroma signal other than the OSD period.

On-screen display apparatus

A data match detecting apparatus which sequentially receives input data comprising plural fields, comprises parameter storage which contains a parameter group comprising plural parameters which are checked to detect a match between the plural fields and the plural parameters; parameter selector for selecting a parameter corresponding to a field input as the input data from the parameter storage and outputting the selected parameter; data comparator for checking match between the parameter output from the parameter selector and the input data; a comparison result storing circuit initialing its storage content to match before a first field of the input data for which match detection should be performed is input, storing a comparison result of a comparison result decider when there is an input field, and outputting its storage content when all the fields of the input data for which match detection should be performed have been input; and the comparison result decider storing match in the comparison result storage when the storage content of the comparison result storage and the comparison result of the data comparator are match.

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Suita, Japan

Tomohiro Okuno