Abstract: A method and system for supplying a digital video signal from a source to a sink are described. The digital video signal includes digital video data for three different colors and a pixel clock signal, such as DVI and HDMI. The digital video data and the pixel clock signal are received at a transmitter which sends a signal representative of the frequency of the pixel clock signal over a cable connecting the transmitter and a receiver. Digital video data for three different colors is sent over three different twisted wire pairs of the cable to the receiver. A local pixel clock signal is generated at the receiver using the signal representative of the frequency of the pixel clock signal. The local pixel clock signal is used to process the received digital video data and recovered digital video data and the local pixel clock signal are output.

Abstract: A digital video signal has a frame rate and a resolution within a range of resolutions. If the resolution of the received digital video signal is in a lower resolution range then it is not compressed or if in a higher resolution range the video color data is compressed by a constant compression ratio. Frames of digital color samples are transmitted and frames of digital color samples are received at the same frame rate. The received compressed digital color samples are expanded by a constant expansion ratio when transmitted in a compressed format and not expanded if transmitted in the uncompressed video format. A digital video signal is output with a resolution the same as the resolution of the original digital video signal.

Abstract: A ventilation system for cleaning contaminated heated air generated by cooking appliances in a food preparation area, such as a kitchen, includes an inlet for contaminated heated air located in the food preparation area, a treatment part for cleaning the contaminated heated air, and an outlet for the cleaned heated air. The cleaned heated air is used as a heat source to heat the building in which the food preparation area is located.

Abstract: Apparatus and methods for reducing cross talk between electrical ports are described. An electronic device comprises a housing for electronic circuitry and has a plurality of ports for connecting electrical devices. Each port includes a connector connected by at least one electrical connection to the electronic circuitry. A connector shield is arranged to provide an electrically conductive loop around which an induced electrical current can flow to reduce cross-talk between ports. A shielding can is part of the connector shield and includes a body formed of a folded sheet of electrically conductive material and an electrical contact for electrically connecting the body to a connector. A face of the body defines a first aperture shaped to receive the connector so that the shielding can may be arranged about the connector to form a part of the electrically conductive loop.

Abstract: A digital video signal has a frame rate and a resolution within a range of resolutions. If the resolution of the received digital video signal is in a lower resolution range then it is not compressed or if in a higher resolution range the video colour data is compressed by a constant compression ratio. Frames of digital colour samples are transmitted and frames of digital colour samples are received at the same frame rate. The received compressed digital colour samples are expanded by a constant expansion ratio when transmitted in a compressed format and not expanded if transmitted in the uncompressed video format. A digital video signal is output with a resolution the same as the resolution of the original digital video signal.

Abstract: A switching device for automatically sharing a pointing input device between a plurality of computers is described. The switching device includes an input for receiving relative pointer position data from the pointing input device and a plurality of outputs, each connectable to a respective one of a plurality of computers. A controller receives the input relative position data and converts the relative pointer position data to absolute pointer position data. Which of the plurality of computers to route input data to is determined based on the absolute pointer position data. Input data is routed to one of the plurality of computers so that a cursor position on a display device of the computer can be controlled by the pointing input device.

Abstract: Apparatus and methods for reducing cross talk between electrical ports are described. An electronic device comprises a housing for electronic circuitry and has a plurality of ports for connecting electrical devices. Each port includes a connector connected by at least one electrical connection to the electronic circuitry. A connector shield is arranged to provide an electrically conductive loop around which an induced electrical current can flow to reduce cross-talk between ports. A shielding can is part of the connector shield and includes a body formed of a folded sheet of electrically conductive material and an electrical contact for electrically connecting the body to a connector. A face of the body defines a first aperture shaped to receive the connector so that the shielding can may be arranged about the connector to form a part of the electrically conductive loop.

Abstract: A method and system for supplying a digital video signal from a source to a sink are described. The digital video signal includes digital video data for three different colours and a pixel clock signal, such as DVI and HDMI. The digital video data and the pixel clock signal are received at a transmitter which sends a signal representative of the frequency of the pixel clock signal over a cable connecting the transmitter and a receiver. Digital video data for three different colours is sent over three different twisted wire pairs of the cable to the receiver. A local pixel clock signal is generated at the receiver using the signal representative of the frequency of the pixel clock signal. The local pixel clock signal is used to process the received digital video data and recovered digital video data and the local pixel clock signal are output.

Abstract: A switching device for automatically sharing a pointing input device between a plurality of computers is described. The switching device includes an input for receiving relative pointer position data from the pointing input device and a plurality of outputs, each connectable to a respective one of a plurality of computers. A controller receives the input relative position data and converts the relative pointer position data to absolute pointer position data. Which of the plurality of computers to route input data to is determined based on the absolute pointer position data. Input data is routed to one of the plurality of computers so that a cursor position on a display device of the computer can be controlled by the pointing input device.

Abstract: There is provided video switching circuitry for use in a KVM switch and similar devices. Video signal switching circuitry can supply video signals from a one of a plurality of video sources connected to the circuit to a display device connected to the circuit. The high data signalling rate signals are converted into a greater number of lower data signalling rate signals for switching by a bus architecture. Also provided are video display systems in which analogue and digital video signals are switched synchronously to allow them to be displayed on common or separate display devices. Also described is a high-resolution monitor digital video data switching device.

Abstract: A system, apparatus and methods for transmitting video and audio data over twisted pairs are described. A differential signal that contains video colour information is transmitted over each twisted pair. Data representing digital samples of at least one audio signal is transmitted on two or more of the twisted pairs as a common mode signal.

Abstract: There is provided video switching circuitry for use in a KVM switch and similar devices. Video signal switching circuitry can supply video signals from a one of a plurality of video sources connected to the circuit to a display device connected to the circuit. The high data signalling rate signals are converted into a greater number of lower data signalling rate signals for switching by a bus architecture. Also provided are video display systems in which analogue and digital video signals are switched synchronously to allow them to be displayed on common or separate display devices. Also described is a high-resolution monitor digital video data switching device.

Abstract: An enterprise KVM system using single twisted pairs to transmit video and data signals is described together with circuitry for the parts of the system and a method of transmitting the signals. The method transmits a video signal and peripheral data over a single twisted pair between a computer and a plurality of peripherals. A sequence of a plurality of analogue video color signals with a vertical synchronisation signal following each analogue video signal is transmitted from the computer to the plurality of peripherals. Peripheral data is transmitted between the plurality of peripherals and computer during the vertical synchronisation signal transmission periods. The KVM enterprise system comprises a plurality of user stations, each user station including a keyboard, mouse and video display connected to a user interface. A plurality of computers are provided each connected to a dongle and supplying video, keyboard and mouse signals to the dongle. A KVM matrix switch is also included.