Patents Assigned to ShareVision Technology, Inc.
  • Patent number: 5367629
    Abstract: A video compression system comprises a pre-processing section, an encoder, and a post-processing section. The pre-processing section employs a median decimation filter which combines median filtering and decimation process. The preprocessing section also employs adaptive temporal filtering and content adaptive noise reduction filtering to provide images with proper smoothness and sharpness to match the encoder characteristics. The encoder employs a two pass look-ahead allocation rate buffer control scheme where the numbers of bits allocated and subsequently generated for each block may differ. In the first pass, the means square error for each block is estimated to determine the number of bits assigned to each block in a frame, In the second pass, the degree of compression is controlled as a function of the total number of bits generated for all the preceding blocks and the sum of the bits allocated to such preceding blocks.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: November 22, 1994
    Assignee: ShareVision Technology, Inc.
    Inventors: Frank J. Chu, C. Lung Yeh