Patents Assigned to Leitch Technology International Inc.
  • Publication number: 20110221957
    Abstract: The method for the representation of video and audio signals on a low-resolution display panel, which includes the steps of: scaling the video or audio frame to fit the display panel, quantization of the video or audio signals to predetermined level values, temporal representation of video data by using the pulse density modulation, sending the signal pulses to the display panel. In further aspect the step of temporal representation contains the anti-flickering signal manipulation technique incorporating maximization of separation of the pulses during the pulse density modulation.
    Type: Application
    Filed: March 14, 2011
    Publication date: September 15, 2011
    Applicant: LEITCH TECHNOLOGY INTERNATIONAL INC.
    Inventors: Artur B. Twarecki, Mark Batchelor
  • Patent number: 7161617
    Abstract: A system for adding monitoring capability to equipment located within a video, audio and/or data production facility. A sampling device is connected to a data communications network and transmits a continuous representation of the video, audio or data being sampled over a data communications network in response to commands from an operator station. To accommodate monitoring of large numbers of sampling devices on a single network, the sampling device may encode and/or compress the video, audio or data being monitored prior to transmitting the sample over the network. The sampling device may also further reduce its contribution to network loading by providing an instant sample of the stream being sampled, such as a single video frame, either a single time, or repeatedly at regular predetermined time intervals.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: January 9, 2007
    Assignee: Leitch Technology International Inc.
    Inventors: Stanley R. Moote, Steven T. Sulte, Artur B. Twarecki, Anthony S. Singh
  • Patent number: 7110457
    Abstract: A system and method for time division multiplexing multiple lower bandwidth signals into a high bandwidth signals such as a high-definition television signal. The invention provides an integrated transmission, distribution and routing signal format in which low-bandwidth signals are embedded in the active video and vertical blanking areas of a high-bandwidth signal. Data from the source data streams, including timing data, is formatted in packets, each packet comprising a plurality of channels. The packets are inserted into the high-bandwidth signal along with a header word providing a ‘data valid bit’ or ‘status bit’ for each of the channels, which identifies valid data words within the packet. The source data streams are accurately reconstituted by de-multiplexing according to header data specifying routing destination, stream ID, stream type, channel usage and stream clock reference for clock recovery at the receiving end.
    Type: Grant
    Filed: May 9, 2000
    Date of Patent: September 19, 2006
    Assignee: Leitch Technology International Inc.
    Inventors: Keping Chen, Semko Szybiak
  • Publication number: 20060158442
    Abstract: The method for the representation of video and audio signals on a low-resolution display panel, which includes the steps of: scaling the video or audio frame to fit the display panel, quantization of the video or audio signals to predetermined level values, temporal representation of video data by using the pulse density modulation, sending the signal pulses to the display panel. In further aspect the step of temporal representation contains the anti-flickering signal manipulation technique incorporating maximization of separation of the pulses during the pulse density modulation.
    Type: Application
    Filed: March 16, 2006
    Publication date: July 20, 2006
    Applicant: LEITCH TECHNOLOGY INTERNATIONAL INC.
    Inventors: Artur Twarecki, Mark Batchelor
  • Patent number: 6608710
    Abstract: An automatic gain control circuit for an optical receiver couples the low level signal produced by an optical detector to a signal amplifier, preferably a double-ended differential amplifier with the optical detector output fed into the high input and the low input coupled to ground, the gain of which is controlled by a negative feedback circuit. The feedback circuit comprises a signal level detection circuit coupled to the amplifier output, such as high-speed Schottky diodes acting in conjunction with an operational amplifier. The Schottky diodes are coupled to ground through AC coupling capacitors, and oriented in opposite directions, so when the amplified signal exceeds a conduction threshold of the Schottky diodes the capacitors are respectively charged and drained, establishing a voltage difference between the input terminals of the operational amplifier.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: August 19, 2003
    Assignee: Leitch Technology International Inc.
    Inventor: Adrian A. Battagin
  • Patent number: 6546113
    Abstract: Watermark data consisting of known two-dimensional codeword patterns are added to a first portion of each video frame by modifying parameters defining the first portion. Limited randomization of the spatial position of the codeword pattern is also provided. During a decoding process, a predictor continuously estimates the current value of the modified parameters. In one embodiment of the present invention, the predictor employs video samples taken from unmodified areas of the frame to provide the estimates. The estimated parameter values are subtracted from the actual parameter values to provide an error signal. Multiple correlators attempt to detect the presence of the codeword pattern in the error signal within a range of spatial locations surrounding a nominal position of the codeword pattern. The use of multiple correlators provides immunity to feasible attacks aimed at damaging or obscuring the watermark.
    Type: Grant
    Filed: March 2, 1999
    Date of Patent: April 8, 2003
    Assignee: Leitch Technology International Inc.
    Inventors: Keith Lucas, William Van Rassel
  • Publication number: 20020163963
    Abstract: A system for adding monitoring capability to equipment located within a video, audio and/or data production facility. A sampling device is connected to a data communications network and transmits a continuous representation of the video, audio or data being sampled over a data communications network in response to commands from an operator station. To accommodate monitoring of large numbers of sampling devices on a single network, the sampling device may encode and/or compress the video, audio or data being monitored prior to transmitting the sample over the network. The sampling device may also further reduce its contribution to network loading by providing an instant sample of the stream being sampled, such as a single video frame, either a single time, or repeatedly at regular predetermined time intervals.
    Type: Application
    Filed: April 19, 2002
    Publication date: November 7, 2002
    Applicant: Leitch Technology International Inc.
    Inventors: Stanley R. Moote, Steven T. Sulte, Artur B. Twarecki, Anthony S. Singh