Patents Examined by Scott Rodgers
  • Patent number: 5974193
    Abstract: Edge Enhanced Noise Reduction (EENR) is a frequency dependent instantaneous compander system. It is applied only in the encoder both to Chrominance and luminance, and is best placed after the horizontal and vertical down sampling filters in the pre-processing stages of an encoder (not shown per se). High frequency, low level information (mainly noise) are reduced significantly in amplitude. In particular, EENR is designed to preserve edge details. In addition, a vertical recursive filter can be used to prevent low level vertical information from being removed by the system. This is partially useful in the luminance path. High level, high frequency components remain virtually unaffected. The system is `transparent` to low frequency information. EENR has been designed to work in conjunction with MPEG encoding presented with source material which is slightly noisy and where the transmission bit rate is being constrained.
    Type: Grant
    Filed: December 20, 1996
    Date of Patent: October 26, 1999
    Assignee: NDS Limited
    Inventor: Charles A. Baudouin