Patents by Inventor Andries P. Hekstra

Andries P. Hekstra has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5596321
    Abstract: Known systems based on stereoscopic video coding and video decoding code with inadequate efficiency because the left-hand picture and the right-hand picture are coded and decoded independently of one another by means of the encoders present in the system. As a result of providing one encoder with switching means to which a signal representing the left-hand picture and a signal representing the right-hand picture are fed, said encoder is able to base the prediction either on the left-hand picture or the right-hand picture, and this improves the prediction and, consequently, the efficiency of the coding.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: January 21, 1997
    Assignee: Koninklijke PTT Nederland N.V.
    Inventors: Andries P. Hekstra, Arian Koster
  • Patent number: 5410307
    Abstract: Known systems based on layered video coding and video decoding code with inadequate efficiency because a new high-resolution picture is predicted by means of switching means present in the system either on a basis of the preceding high-resolution picture or on the basis of an instantaneous low-resolution picture. According to the invention, designing the switching means for a adjustment of a ratio of the signal representing a preceding high-resolution picture and the signal representing the instantaneous low-resolution picture and for then adding both adjusted signals achieves a gain of 3 dB in the prediction with the correct ratio, thus resulting in an improvement in the coding efficiency.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: April 25, 1995
    Assignee: Koninklijke PTT Nederland N.V.
    Inventors: Andries P. Hekstra, Arian Koster, Dolf A. Schinkel