Video data is compressed, at a first site, by a transform scaling data compressor (12), and carrier signals are modulated with audio and digital data by a delta modulation data modulator (14) and a delta-sigma modulation data modulator (16) respectively. Their output signals are combined by a multichannel...http://www.google.de/patents/US5182642?utm_source=gb-gplus-sharePatent US5182642 - Apparatus and method for the compression and transmission of multiformat data
