Patents Assigned to AVT Communications Limited
  • Patent number: 5500685
    Abstract: A digital Wiener filtering method is proposed which applies motion compensation by successive approximations of increasing resolution to determine displacement vectors for two successive image frames, a vectors defining a real displacement only being applied to a block of one of the frames when the mean absolute error associated with that vector is not greater than a given fraction of the mean absolute error between that block and the corresponding block of the other frame. The current frame is then filtered block-by-block, with the blocks overlapping. In this filtering, each block is a 3D volume of pixels from the current frame and blocks selected from the preceding and succeeding frames so as to correspond according to the displacement vectors. In one embodiment, the filtering comprises applying a 3D FFT to convert to a power spectrum in the frequency domain, followed by attenuation according to a Wiener filter and conversion from the frequency domain by the inverse FFT.
    Type: Grant
    Filed: October 14, 1994
    Date of Patent: March 19, 1996
    Assignee: AVT Communications Limited
    Inventor: Anil C. Kokaram