Abstract: A video signal adjustment system that is capable of being connected between a server and a console includes: a server unit that is connected to the server; a main unit that is connected to the server unit, and includes a first adjustment portion that adjusts gain and frequency characteristic of a video signal output from the server; and a console unit that is connected between the main unit and the console, and includes a second adjustment portion that adjusts gain, frequency characteristic, and delay of the video signal output from the main unit.

Abstract: A signal transmission system includes a transmitting device and a receiving device. The transmitting device includes a superimposition portion that superimposes at least one synchronizing signal on at least one video signal among a plurality of video signals, and outputs the synchronizing signal and the video signal as a superimposition signal to a receiving device. The receiving device includes a separation portion that separates the superimposition signal into the synchronizing signal and the video signal, a first adjustment portion that adjusts an amount of delay of the separated video signal to another video signal, and a second adjustment portion that adjusts an amount of delay of the separated synchronizing signal.

Abstract: A KVM switch includes: server units respectively connected to computers; user units respectively connected to input/output devices for transmitting signals to the computers and receiving signals from the computers; and a main unit that connects the server units and the user units. Each of the server units, user units and main unit is a communication unit and includes: a first part communicating with another communication unit to inform the above another communication unit of unit type information about the communication unit and receive unit type information about the above another communication unit therefrom; and a second part controlling communications with the above another communication unit on the basis of the unit type information acquired from the above another communication unit.

Abstract: A KVM switch including server units that are respectively connected to computers units, user units that are respectively connected to input-output units inputting and outputting a signal to the computer units, and a main unit that connects the server units and the user units selectively. The input-output unit switches between the computer units where the signal is input and output. The server unit has a first reference signal generator that generates a first reference signal used for a distortion control of a picture signal. The main unit has a first controller receiving the first reference signal and controlling the distortion of the picture signal and a second reference signal generator generating a second reference signal used for the distortion control of the picture signal. The user unit has a second controller that receives the second reference signal and controls the distortion of the picture signal.

Abstract: A switching device that selectively switches connections to a predetermined terminal among two or more terminals connected to servers, and can be remote-controlled via a network, includes a network interface circuit to be connected to the network, an image processing unit that includes an image compression circuit for compressing image signals outputted from the servers, and a controller that changes a compression method or compression rate to be used at the image compression circuit in accordance with the congestion level of the network.

Abstract: A video signal adjustment system that is capable of being connected between a server and a console includes: a server unit that is connected to the server; a main unit that is connected to the server unit, and includes a first adjustment portion that adjusts gain and frequency characteristic of a video signal output from the server; and a console unit that is connected between the main unit and the console, and includes a second adjustment portion that adjusts gain, frequency characteristic, and delay of the video signal output from the main unit.

Abstract: A switching device that selectively switches connections to a predetermined terminal among two or more terminals connected to servers, and can be remote-controlled via a network, includes a network interface circuit to be connected to the network, an image processing unit that includes an image compression circuit for compressing image signals outputted from the servers, and a controller that changes a compression method or compression rate to be used at the image compression circuit in accordance with the congestion level of the network.

Abstract: A switching device that selectively switches connections to a predetermined terminal among two or more terminals connected to servers, and can be remote-controlled via a network, includes a network interface circuit to be connected to the network, an image processing unit that includes an image compression circuit for compressing image signals outputted from the servers, and a controller that changes a compression method or compression rate to be used at the image compression circuit in accordance with the congestion level of the network.

Abstract: A switch selectively switches terminals to which a computer is connected, and can be remotely operated by a remote-control computer connected to a predetermined network. This switch includes: an information acquiring unit that acquires cursor location information from the remote-control computer; an image extracting unit that extracts a cursor peripheral image from an image storing unit that stores an image obtained from the computer, based on the cursor location information acquired by the information acquiring unit; and a cursor image transmitting unit that transmits the cursor peripheral image, extracted by the image extracting unit, to the remote-control computer.

Abstract: A switch selectively switches terminals to which a computer is connected, and that can be remotely operated by a remote-control computer connected to a predetermined network. This switch includes: an information acquiring unit that acquires cursor location information from the remote-control computer; an image extracting unit that extracts a cursor peripheral image from an image storing unit that stores an image obtained from the computer, based on the cursor location information acquired by the information acquiring unit; and a cursor image transmitting unit that transmits the cursor peripheral image, extracted by the image extracting unit, to the remote-control computer.

Abstract: A signal transmission system includes a transmitting device and a receiving device. The transmitting device includes a superimposition portion that superimposes at least one synchronizing signal on at least one video signal among a plurality of video signals, and outputs the synchronizing signal and the video signal as a superimposition signal to a receiving device. The receiving device includes a separation portion that separates the superimposition signal into the synchronizing signal and the video signal, a first adjustment portion that adjusts an amount of delay of the separated video signal to another video signal, and a second adjustment portion that adjusts an amount of delay of the separated synchronizing signal.

Abstract: A selector that selectively makes connections between USB devices attached to a console side thereof and electronics devices connected to a host side thereof. The selector includes a USB host circuit controlling the USB devices, and USB device emulation circuits being respectively provided for the electronics devices and maintaining the connections with the electronics devices even while the USB devices are selectively being changed, and a control circuit coupling the USB host circuit and USB device emulation circuits.

Abstract: A KVM switch includes: server units respectively connected to computers; user units respectively connected to input/output devices for transmitting signals to the computers and receiving signals from the computers; and a main unit that connects the server units and the user units. Each of the server units, user units and main unit is a communication unit and includes: a first part communicating with another communication unit to inform the above another communication unit of unit type information about the communication unit and receive unit type information about the above another communication unit therefrom; and a second part controlling communications with the above another communication unit on the basis of the unit type information acquired from the above another communication unit.

Abstract: A KVM switch including server units that are respectively connected to computers units, user units that are respectively connected to input-output units inputting and outputting a signal to the computer units, and a main unit that connects the server units and the user units selectively. The input-output unit switches between the computer units where the signal is input and output. The server unit has a first reference signal generator that generates a first reference signal used for a distortion control of a picture signal. The main unit has a first controller receiving the first reference signal and controlling the distortion of the picture signal and a second reference signal generator generating a second reference signal used for the distortion control of the picture signal. The user unit has a second controller that receives the second reference signal and controls the distortion of the picture signal.

Abstract: A selector that selectively makes connections between USB devices attached to a console side thereof and electronics devices connected to a host side thereof. The selector includes a USB host circuit controlling the USB devices, and USB device emulation circuits being respectively provided for the electronics devices and maintaining the connections with the electronics devices even while the USB devices are selectively being changed, and a control circuit coupling the USB host circuit and USB device emulation circuits.

Abstract: A switch selectively switches terminals to which a computer is connected, and that can be remotely operated by a remote-control computer connected to a predetermined network. This switch includes: an information acquiring unit that acquires cursor location information from the remote-control computer; an image extracting unit that extracts a cursor peripheral image from an image storing unit that stores an image obtained from the computer, based on the cursor location information acquired by the information acquiring unit; and a cursor image transmitting unit that transmits the cursor peripheral image, extracted by the image extracting unit, to the remote-control computer.

Abstract: A switching device that selectively switches connections to a predetermined terminal among two or more terminals connected to servers, and can be remote-controlled via a network, includes a network interface circuit to be connected to the network, an image processing unit that includes an image compression circuit for compressing image signals outputted from the servers, and a controller that changes a compression method or compression rate to be used at the image compression circuit in accordance with the congestion level of the network.

Abstract: An auxiliary keyboard has a first input mode and a second input mode and comprises an input mode switching key, a mode switching unit for switching between the first input mode and second input mode at each depression of the input mode switching key without posting the depression to a computer, a key code sending unit for sending, when the key of the auxiliary keyboard is depressed, a predetermined first key code corresponding to the depressed key of the auxiliary keyboard either in the first input mode or in the second input mode, and a mode correcting unit for correcting, when the input mode of the main keyboard is switched into the numeric data input mode, the numeric data input mode to the character data input mode.

Abstract: An auxiliary keyboard has a first input mode and a second input mode and comprises an input mode switching key, a mode switching unit for switching between the first input mode and second input mode at each depression of the input mode switching key without posting the depression to a computer, a key code sending unit for sending, when the key of the auxiliary keyboard is depressed, a predetermined first key code corresponding to the depressed key of the auxiliary keyboard either in the first input mode or in the second input mode, and a mode correcting unit for correcting, when the input mode of the main keyboard is switched into the numeric data input mode, the numeric data input mode to the character data input mode.