A system for automatically adapting the mean sound level of a television receiver. The system for automatically adapting the mean sound level of a television receiver comprises an adapting module comprising both a video adapting circuit comprising at least one additional input highpass filter and a fixed-gain...http://www.google.com.tw/patents/US5631714?utm_source=gb-gplus-share專利 US5631714 - Apparatus for automatically adapting the mean sound level of a television receiver
