System for recording and/or reproducing an audio signal which has been converted into a digital signal Patent #: 4246615
ApplicationNo. 06/316328 filed on 10/29/1981
US Classes:386/100, Fault condition compensation348/481Plural (e.g., stereo or SAP)
ExaminersPrimary: Richardson, Robert L.
Attorney, Agent or Firm
International ClassesH04N 7/085 (20060101)
H04N 5/928 (20060101)
H04N 7/084 (20060101)
H04N 5/923 (20060101)
Foreign Application Priority Data1980-10-31 JP
AbstractA video signal is recorded with the associated audio signal inserted as a PCM digital signal in the back porch portions of the horizontal blanking intervals. In order to prevent the video pre-emphasis that is used in high-density recording from degrading the PCM digital signal, the video signal and the PCM digital signal are provided with separate and independent degrees of pre-emphasis. Upon playback, the video signal and the PCM digital signal are provided with corresponding independent respective amounts for de-emphasis. In order to fit a sufficient number of bits into the blanking intervals to provide high quality audio, the back porch portion is first extended by replacing the standard horizontal synch pulses with narrow pulses, so that the following back porch portions are correspondingly elongated.