Abstract: A KVM switch cable is described. The KVM switch cable transmits and converts signals between a USB interface and a PS/2 interface for a computer and a KVM switch. Therefore, the life-span and application scope of the KVM switch with PS/2 interfaces can be efficiently extended. The KVM switch cable has a set of computer connectors, a transmitting cable, and a combination connector, and further has a signal converting device installed in the set of computer connectors or the combination connector. The transmitting cable can transmit video signals of the computer to the KVM switch, mouse and keyboard signals to the computer, and can further simultaneously transmit microphone signals and speaker signals for the computer and the KVM switch.

Abstract: The method and apparatus are provided for several audio signal processing apparatuses to share at least one audio output device. Several audio signals sent from the audio signal processing apparatuses are received. The DC levels of the audio signals are shifted to a predetermined value. One of the adjusted audio signals is then selected for signal-transmitting to the audio output device. Afterwards, the DC level of the selected audio signal is re-adjusted to the predetermined value.

Abstract: A method for image compression is described. The method compresses computer images for efficient transfer of consecutive compressed images through a network. The method comprises loading two consecutive images, fuzzy comparing the two consecutive images, calculating the total different number between the two consecutive images, and determining an encoding algorithm, such as run-length and delta-modulation (RLEDM) or JPEG, according to the total different number. The fuzzy comparison eliminates deviations caused by capturing errors. The RLEDM encoding algorithm of the invention only deals with image differences between the two consecutive images, including line pattern indexes and line patterns, and depends on a minimum encoding size rule to further determine the encoding algorithm, such as a direct encoding, a run-length encoding or a delta-modulation encoding.

Abstract: A resource sharing apparatus includes an application specific integrated circuit and a central processing unit. The application specific integrated circuit includes a number of hubs, a number of device controllers for stimulating the peripheral apparatus, a bus, a host controller, and a root hub. Each of the hubs and the root hub has a host port and a number of peripheral ports. The host port of each hub is coupled to one personal computer, and the peripheral ports of each hub are coupled to one device controller and the peripheral apparatus. Some peripheral apparatus are coupled to the peripheral ports of the root hub, and the host port of the root hub is coupled to the host controller. The device controllers, the host controller, and the central processing unit, coupled to each other via the bus, control the operation of the resource sharing apparatus.

Abstract: A control system for controlling a plurality of target computers is described. The control system has at least a local computer and a control apparatus. The local computer has a wireless signal transmission module for transmitting a local control signal. The control apparatus has a wireless signal receiving module for receiving the local control signal. The control apparatus sends the local control signal, via a KVM switch, to the target computers for controlling the target computers. The wireless signal transmission module is, for example, a general wireless card. Wireless communication can be performed using general wireless communication protocols. The wireless signal reception module is, for example, an access point.

Abstract: A video card is controlled by a control unit to output video data to a display or through a network. The video card includes a network interface, an interface controller and a bus interface. The network interface is connected to the network to transfer the video data. The interface controller is coupled to the network interface and controlled by the control unit to output the video data to the display or through the network interface. The bus interface is coupled between the interface controller and the control unit and is for inputting the video data from the control unit to the interface controller.

Abstract: A control apparatus for controlling a plurality of computers is described. The control apparatus includes a memory, a clock generator, a clock switch circuit, and a main module. The clock switch circuit switches between a system clock and a corresponding clock of a digital video signal. The main module directly stores the digital video signal into the memory according to the corresponding clock through the clock switch circuit. The main module reads the digital video signal from the memory according to the system clock. The main module also receives a remote control signal sent from a remote computer to control the plurality of computers.

Abstract: The method and apparatus are provided for several audio signal processing apparatuses to share at least one audio output device. Several audio signals sent from the audio signal processing apparatuses are received. The DC levels of the audio signals are shifted to a predetermined value. One of the adjusted audio signals is then selected for signal-transmitting to the audio output device. Afterwards, the DC level of the selected audio signal is re-adjusted to the predetermined value.

Abstract: When the destinations of local electrical signals are local computers, the local electrical signals are transmitted to the corresponding destination local computers via the keyboard video mouse (KVM) switch directly. When the destinations of the local electrical signals are remote computers, at least one network packet having multiple data sections for correspondingly storing the local electrical signals is generated by the current KVM switch referring to the local electrical signals. A communication is established among a plurality of the KVM switches using a network protocol, for communicating the network packets thereof. At least one remote electrical signal is obtained from another network packet transmitted by another KVM switch, and then is transmitted to the corresponding destination local computer.

Abstract: A plurality of local and remote computers share a plurality of local manipulating devices, and the connection agreements of the computers and the manipulating devices are different. First electrical signals from these manipulating devices are received, and each of the first electrical signals complies with the connection agreement of its source manipulating device. Each first electrical signal is then converted to a standard packet. The paths of these standard packets are routed between the manipulating devices and the computers. Afterwards, each standard packet is converted to a second electrical signal which complies with the connection agreement of its destination computer.

Abstract: A keyboard, video, mouse, and storage (KVMS) switch is described. The KVMS switch has a server computer interface, a keyboard-mouse-monitor interface, a storage device, and a control device. The server computer interface connects to at least one server computer and the keyboard-mouse-monitor interface connects to a keyboard, a mouse, and a monitor. The storage device with data stored therein is configured inside the KVMS to update and install software for the server computers. Therefore, the security and efficiency of server computer management are enhanced.

Abstract: A cable length detection apparatus is provided to detect the length of a cable having at least three pairs of wires for transmitting video signals. The cable length detection apparatus has a signal compressing circuit, a signal converting circuit and a length calculating circuit. The signal compressing circuit compresses an electrical signal into one pair of wires. The signal converting circuit converts the electrical signal transmitted by the pair of wires into a value. The length calculating circuit then calculates the length of the cable according to the value.

Abstract: A local electrical signal and a remote electrical signal are received for switching. When destinations of the local and remote electrical signals are the same local signal input device, only one of them is allowed to be transmitted to the destined local signal input device. When destinations of the local and remote electrical signals are at least one remote signal input device, only one of them is allowed to be transmitted to the destined remote signal input device.

Abstract: The method and apparatus are provided for several audio signal processing apparatuses to share at least one audio output device. Several audio signals sent from the audio signal processing apparatuses are received. The DC levels of the audio signals are shifted to a predetermined value. One of the adjusted audio signals is then selected for signal-transmitting to the audio output device. Afterwards, the DC level of the selected audio signal is re-adjusted to the predetermined value.

Abstract: The disclosed method and apparatus are provided for several audio signal processing apparatuses to share at least one audio output device. Several audio signals sent from the audio signal processing apparatuses are received. The DC levels of the audio signals are shifted to a predetermined value. One of the adjusted audio signals is then selected for signal-transmitting to the audio output device. Afterwards, the DC level of the selected audio signal is re-adjusted to the predetermined value.

Abstract: A KVM switch cable is described. The KVM switch cable transmits and converts signals between a USB interface and a PS/2 interface for a computer and a KVM switch. Therefore, the life-span and application scope of the KVM switch with PS/2 interfaces can be efficiently extended. The KVM switch cable has a set of computer connectors, a transmitting cable, and a combination connector, and further has a signal converting device installed in the set of computer connectors or the combination connector. The transmitting cable can transmit video signals of the computer to the KVM switch, mouse and keyboard signals to the computer, and can further simultaneously transmit microphone signals and speaker signals for the computer and the KVM switch.

Abstract: A resource sharing apparatus includes an application specific integrated circuit and a central processing unit. The application specific integrated circuit includes a number of hubs, a number of device controllers for stimulating the peripheral apparatus, a bus, a host controller, and a root hub. Each of the hubs and the root hub has a host port and a number of peripheral ports. The host port of each hub is coupled to one personal computer, and the peripheral ports of each hub are coupled to one device controller and the peripheral apparatus. Some peripheral apparatus are coupled to the peripheral ports of the root hub, and the host port of the root hub is coupled to the host controller. The device controllers, the host controller, and the central processing unit, coupled to each other via the bus, control the operation of the resource sharing apparatus.

Abstract: A method for image compression is described. The method compresses computer images for efficient transfer of consecutive compressed images through a network. The method comprises loading two consecutive images, fuzzy comparing the two consecutive images, calculating the total different number between the two consecutive images, and determining an encoding algorithm, such as run-length and delta-modulation (RLEDM) or JPEG, according to the total different number. The fuzzy comparison eliminates deviations caused by capturing errors. The RLEDM encoding algorithm of the invention only deals with image differences between the two consecutive images, including line pattern indexes and line patterns, and depends on a minimum encoding size rule to further determine the encoding algorithm, such as a direct encoding, a run-length encoding or a delta-modulation encoding.

Abstract: The present invention provides an electronic switching device for a universal serial bus (USB) interface, which can connect several different electronic devices each having a universal serial bus (USB) interface when needed. By manually enabling a switch of the electronic switching device for a universal serial bus (USB) interface, a trigger signal generated from a trigger signal generator will be outputted to a control signal generator to generate a control signal for connecting related electronic devices. A delay signal generator can be added to avoid the intermediate devices being operated unintentionally.

Abstract: An intelligent computer switch is described. The intelligent computer switch has an automatic detection capacity to control a plurality of computers with at least one keyboard, at least one mouse and at least one monitor. The intelligent computer switch comprises an input port, a control device, an output port, and a plurality of computer connection ports. The input port receives input commands and data, and the output port sends output commands and data. While a series connection cable connected to the input port, the intelligent computer switch is determined to be a slave. While the series connection cable is not connected to the series connection cable, the intelligent computer switch is determined to be a master. The intelligent computer switch further comprises an on-screen display function and an authority-setting function with at least 4 sets of passwords for different users.