Resources Contact Us Home
Spatial compression and decompression for video

Image Number 3 for United States Patent #5675382.

A spatial compression and decompression system for color video data wherein a video stream is generated by a charge-coupled device with red, green and blue pixel elements. In a first compression stage, the 5-bit color data from each element is processed in turn. This step involves reading out from a lookup memory a 3-bit category (or compressed value) and 5-bit output value based on the 5-bit color data, a 5-bit previous value that represents same color data for a neighboring pixel and a 1-bit table select signal that determines in which of two similar tables the lookup is performed. The 3-bit category data for a pixel's three elements are combined and used as a 9-bit index into a Huffman table that performs the second stage of compression. Each Huffman table entry includes a variable-length Huffman code that represents more common categories with fewer bits, which provides additional compression over the first stage. The Huffman table reads out the code of the particular 9-bit category used for the lookup. This code is packed into an output buffer and transmitted to the decompressor that will unpack for display or store the resulting compressed data stream. In the first decompression stage, each Huffman code in the compressed data stream is decoded using no more than two compares and one table lookup into an inverse Huffman decode table. The resulting 9-bit category is used as an index into one of two similar inverse lookup tables, which outputs the appropriate 16-bit uncompressed data value.

  Recently Added Patents
Testing apparatus and testing method for telephone apparatus
Image processing apparatus, image processing method, and program
Phosphor, light emitting apparatus, and liquid crystal display apparatus using the same
Lookup front end packet input processor
Feedback method and processing system for policy installation failures
Method for facilitating assessment of a coursework answer and moderating the assessment
Electrophoresis display having touch screen and method for driving the touch screen
  Randomly Featured Patents
Continuous casting apparatus having oscillator for mold tube
Wiring board and semiconductor package using the same
Contacts for CMOS imagers and method of formation
Sprayable surface defect detection composition and method of using same
Method and system for evaluation of the hemodynamic model in depression for diagnosis and treatment
Method and apparatus for directing conditioned air to a spinning machine
Security door hinge system with locking elements
Copolymerization of polyethercyclicpolyols with epoxy resins
Method for plasma etch of ruthenium
Electrophotographic apparatus capable of selectively using cut sheet and continuous paper and method therefor