Patents by Inventor Albert E. Rackett

Albert E. Rackett 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: 6873654
    Abstract: A technique for digital video processing in a predictive manner is provided. In one embodiment, a method for processing digital video signals for live video applications comprises providing video data that comprise a plurality of frames, identifying a first frame and a second frame in the frame sequences, and processing the information of the first frame and the information of the second frame to determine a quantization step for the second frame. The step of processing the information of the first frame and the information of the second frame further comprises calculating a sigmaSAD value for the second frame, calculating a divisor value for the second frame, and calculating the quantization step for the second frame. In another embodiment, a system for processing digital video signals for live video applications comprises a memory unit within which a computer program is stored. The computer program instructs the system to process digital video in a predicative manner.
    Type: Grant
    Filed: May 15, 2001
    Date of Patent: March 29, 2005
    Assignee: Redrock Semiconductor, Inc
    Inventor: Albert E. Rackett
  • Patent number: 6668095
    Abstract: This invention relates to systems and methods for increasing image compression. The systems and methods are improvements applicable to encoder/decoders which compress images by, inter alia, transforming non-overlapping independent blocks of pixels into a frequency domain and then quantizing the resulting frequency domain coefficients. The invention achieves increased compression by predicting low frequency coefficients of a block from, preferably, the average intensities, or zero frequency coefficients, of the block and its adjacent blocks. In an encoder, the low frequency coefficients are predicted, are then subtracted from the actual transform coefficients, and the difference coefficients are transmitted to a decoder. In the decoder, the low frequency coefficients are again predicted, are added to the received difference coefficients, and the resulting actual transform coefficients are used to reconstruct an image.
    Type: Grant
    Filed: April 17, 2001
    Date of Patent: December 23, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Albert E. Rackett
  • Patent number: 6567469
    Abstract: A method for identifying an optimum motion vector for a current block of pixels in a current picture in a process for performing motion estimation. The method is implemented by evaluating a plurality of motion vector candidates for the current block of pixels by, for each motion vector candidate, and calculating an error value that is representative of the differences between the values of the pixels of the current block of pixels and the values of a corresponding number of pixels in a reference block of pixels. While evaluating each motion vector candidate, the error value is checked, preferably at several points, while calculating the error value, and the evaluation is aborted for that motion vector candidate upon determining that the error value for that motion vector candidate exceeds a prescribed threshold value. The motion vector candidate that has the lowest calculated error value is selected as the optimum motion vector for the current block of pixels.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: May 20, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventor: Albert E. Rackett
  • Publication number: 20020071610
    Abstract: This invention relates to systems and methods for increasing image compression. The systems and methods are improvements applicable to encoder/decoders which compress images by, inter alia, transforming non-overlapping independent blocks of pixels into a frequency domain and then quantizing the resulting frequency domain coefficients. The invention achieves increased compression by predicting low frequency coefficients of a block from, preferably, the average intensities, or zero frequency coefficients, of the block and its adjacent blocks. In an encoder, the low frequency coefficients are predicted, are then subtracted from the actual transform coefficients, and the difference coefficients are transmitted to a decoder. In the decoder, the low frequency coefficients are again predicted, are added to the received difference coefficients, and the resulting actual transform coefficients are used to reconstruct an image.
    Type: Application
    Filed: April 17, 2001
    Publication date: June 13, 2002
    Applicant: Philips Electronics North America Corporation
    Inventor: Albert E. Rackett
  • Patent number: 6317522
    Abstract: This invention relates to a system and method for reducing blocking artifacts introduced by current compression algorithms that compress images as independent blocks of pixels. Preferably, the methods of the invention include determining block-to-block differences in edge pixels or in overall intensities between adjacent pixel blocks, selecting pixel blocks for post-processing that appear to be in relatively featureless regions of the image, interpolating the block-to-block edge differences into a error correction matrix, and then subtracting the error correction matrix from the original pixel block. These methods are preferably implemented in special software routines that execute on micro-processor based systems or on digital signal processor based systems optimized for image decoding.
    Type: Grant
    Filed: December 3, 1998
    Date of Patent: November 13, 2001
    Assignee: Philips Electronics North America Corp.
    Inventor: Albert E. Rackett
  • Patent number: 6282322
    Abstract: This invention relates to systems and methods for increasing image compression. The systems and methods are improvements applicable to encoder/decoders which compress images by, inter alia, transforming non-overlapping independent blocks of pixels into a frequency domain and then quantizing the resulting frequency domain coefficients. The invention achieves increased compression by predicting low frequency coefficients of a block from, preferably, the average intensities, or zero frequency coefficients, of the block and its adjacent blocks. In an encoder, the low frequency coefficients are predicted, are then subtracted from the actual transform coefficients, and the difference coefficients are transmitted to a decoder. In the decoder, the low frequency coefficients are again predicted, are added to the received difference coefficients, and the resulting actual transform coefficients are used to reconstruct an image.
    Type: Grant
    Filed: December 3, 1998
    Date of Patent: August 28, 2001
    Assignee: Philips Electronics North America Corp.
    Inventor: Albert E. Rackett
  • Patent number: 4704628
    Abstract: An apparatus and method for signal processing employing intraframe and interframe variable prediction transform coding. Images are represented by sequential frames of two-dimensional arrays of digital signals. The digital signals are transformed to form transform coefficients for each frame. Predicted transform coefficients are formed using sets of variable prediction factors. The predicted transform coefficients for each frame are compared with corresponding actual transform coefficients for the frame to form transform coefficient difference signals. The difference signals are processed to control their range of values. The processed difference signals are statistically coded such that the more frequently occurring values are represented by shorter code lengths and the less frequently occurring values are represented by longer code lengths. The coded signals are stored in a buffer memory for transmission.
    Type: Grant
    Filed: July 16, 1986
    Date of Patent: November 3, 1987
    Assignee: Compression Labs, Inc.
    Inventors: Wen-hsiung Chen, James P. Elliott, Robert E. G. Newell, Ralph E. Nichols, Albert E. Rackett