Abstract: Still image capture under computer control. The computer is instructed to capture the still image capture at an occurrence of a trigger and, subsequently in time, captures the still image. In embodiments, the instructions can be made through a graphical user interface (GUI) displayed on a monitor or a keyboard coupled to the computer. The instruction can start a timed count until the still image is captured. In embodiments the trigger can be an external event, such as sound or motion sensed by appropriate transducers. In yet other embodiments, the computer issues a notification of an occurrence of a capture or a warning of an impending capture.

Abstract: A method and conferencing system for communicating data between a plurality of nodes of the conferencing system. According to a preferred embodiment, data is formatted into a conferencing object. The formatted data is transmitted from a source node via a communications means of the conferencing system to at least one receiving node. The conferencing object comprises a content portion having at least one data element, and a descriptor portion having effectiveness information, wherein the effectiveness information describes the value of the at least one data element of the content portion.

Abstract: Power supply apparatus includes a converter which converts a commercial AC voltage into a DC voltage. An inverter converts the DC voltage into a high frequency voltage. The high frequency voltage is voltage-transformed by a transformer, and then rectified and smoothed by a rectifier and a smoothing reactor into a DC voltage. This DC voltage is applied between a workpiece and a torch. A high frequency voltage generator generates a high frequency voltage and applies it to a primary winding of a coupling transformer. A boosted high frequency voltage is induced in a first secondary winding and applied between the workpiece and the torch, so that arcing is initiated. The coupling transformer includes a second secondary winding in which another high frequency voltage is induced. The high frequency voltage induced in the second secondary winding is converted into a DC voltage by a diode and a smoothing capacitor for application between the workpiece and the torch, so that the arcing is sustained.

Abstract: A power supply apparatus for a plasma arc utilizing equipment providing an output current nearly equal to an input current includes a first converter for converting an AC voltage to a DC voltage. The DC voltage is converted to a high frequency voltage by an inverter. The output of the inverter is converted through a second converter to a DC voltage which is applied between a torch and a workpiece. A current detector detects an output current flowing between the second converter and the workpiece. A voltage detector detects an output voltage between the torch and the workpiece. A multiplier multiplies the output current and the output voltage to provide a signal representative of an output power. A comparator compares the output power representative signal with a first preset value.

Abstract: Image data in an initial color format (e.g., subsampled YUV9 data) is color converted to a selected RGB16 color format by executing compiled computer program code. The same compiled computer program code can be used to convert the image data in the initial color format into image data in any of two or more different RGB16 formats. In a preferred embodiment, lookup tables (configurable during run-time processing) are used to make the color conversion processing more efficient. The selected RGB16 color format can be changed during run-time processing, in which case certain lookup tables are reinitialized for the newly selected RGB16 format.

Abstract: A computer system with an operating system and a data-processing system running on a host processor, and a receiver. The receiver sends interrupt signals to the operating system after the receiver has received data signals. The operating system establishes interrupt times and passes the interrupt signals to the data-processing system. The data-processing system accesses the data signals from the receiver and only partially processes the data signals during the interrupt times. The operating system also receives clock interrupt signals, which it passes on to the data-processing system. The data-processing system completes the processing of the data signals during the clock interrupt times that the operating system establishes in response to the clock interrupt signals.

Abstract: Conferencing nodes transmit messages back and forth to negotiate characteristics for their conferencing session. The messages identify different sets of conferencing capabilities supported by the conferencing nodes. A first node transmits a request to a second node, wherein the request identifies a first set of conferencing capabilities of the first node. The second node transmits a response to the first node, wherein the response identifies a second set of conferencing capabilities of the second node and the second set is a subset of the first set. The first node and second node conduct conferencing based on the second set.

Abstract: A visual indicator is employed on screen at each station of a video teleconference to inform respective participants of their place in a talk request queue. The indicators are controlled automatically in accordance with designer-chosen conference parameters. Optional system failsafe mechanisms protect against system lock-up.

Abstract: There is provided herein a method, apparatus, and storage medium for processing data. According to one embodiment, encoded data is received by a playback engine of a computer system. A decoder of the playback engine decodes the encoded data. A capture engine of the computer system is notified to encode the decoded data. The decoded data is encoded with an encoder of the capture engine.

Abstract: In the system of the present invention an individual displayed pixel is a weighted combination of a video pixel and a graphics pixel. For example, a pixel displayed on a monitor may be three-quarters graphics and one-quarter video. In this system a color lookup table providing a red, a green and a blue lookup table output value is extended to provide a further lookup table output value. The further lookup table output value is a weight value representative of the relative weights of a video pixel and a corresponding graphics pixel. The weight value is applied to a matrix multiplier which also receives video pixel information and graphics pixel information. The matrix multiplier determines a weighted combination of the video and graphics pixel information according to the weight value to provide a blended pixel. A YUV standard to RGB standard conversion matrix is provided within in order to receive video signals in a YUV format and apply the video signals to the matrix multiplier in an RGB format.

Abstract: Multimedia signals are encoded with certain values to control a user's access to the decoding of the multimedia signals. In a preferred embodiment in which the multimedia signals contain video signals, a lock word and a checksum value are encoded into each frame header of the video stream. The lock word is the result of applying a specified hash function to the checksum value for the current frame and a specified access word. A decoder will decode the encoded video signals for the current frame only if the result of applying the hash function to the access word (received from a decoding application) and the checksum value (retrieved from the frame header) is equal to the lock word (retrieved from the frame header). If the hash function result does not equal the lock word, then the decoder assumes that decode access is not permitted. In that case, the decoder will not decode the current frame and instead will send an error message to the decoding application (preferably after a specified delay).

Abstract: Host translation of guest keyboard events is blocked to effectively isolate a guest keyboard from a host keyboard during applications sharing. A guest keyboard driver translates guest keyboard events which are transmitted to a host for use in shared applications. A patch instruction is written over a host keyboard event module which causes a jump to a patch subroutine when an attempt is made to deposit host keyboard events in the storage queue. Host keyboard events are marked by the patch subroutine and the marked host events are deposited in a shadow queue which is disposed in parallel with the host storage queue. Translated guest events also are deposited in the shadow queue. Raw host and guest keyboard events are stored in the host storage queue. When a shared application requires data from the host storage queue, a call for a translation of the outgoing data is made.

Abstract: Selecting a Huffman table to encode a set of signals, such as video signals, from a set of predefined Huffman tables. A histogram is generated for the set of signals and used to determine the number of bits to encode the set of signals for each of the predefined Huffman tables. The Huffman table that provides the smallest number of bits to encode is selected for encoding the set of signals into the encoded bitstream. In a preferred embodiment, a dynamic Huffman table is also generated for the set of signals and used to estimate the number of bits to encode the set of signals including the number of bits to encode the dynamic Huffman table. If using the dynamic Huffman table results in fewer bits in the encoded bitstream, then the dynamic Huffman table is used (and explicitly encoded in the bitstream) instead of the selected predefined Huffman table.

Abstract: A graphical user interface control element. A computer system for interfacing with a user has a display device and a user input peripheral device for controlling a positioning element on the display device. The positioning element has a location and an active status corresponding to whether the positioning element is activated or not activated by the user. A control button is displayed on the display means, the control button having a three-dimensional appearance and at least first and second regions. The active status and location of the positioning element are monitored to determine whether a region of the control button is being pushed by the positioning device. The appearance of the control button on the display means is altered in accordance with the region being pushed by the positioning device so that the control button appears to be fitted toward the pushed region by the positioning device to provide graphical feedback to the user.

Abstract: A computer-implemented method and apparatus for encoding video pictures of a sequence of video pictures, wherein each picture is defined by one picture type of a plurality of picture types and each picture has a complexity. According to a preferred embodiment, the complexity of each picture type is estimated to provide a complexity estimate for each picture type. Encoding a picture at an average quantization level produces an encoded bit stream having a codesize related to the complexity of the picture, and each picture type is associated with a target codesize. An average quantization level is determined for the first picture of each picture type in accordance with the target codesize and complexity estimate of each of the first pictures, respectively. The first picture of each picture type is then encoded at its respective average quantization level.

Abstract: A distributed protocol for allocation of multicast addresses. A first node of a network sends an address request message identifying (1) a requested in multicast address, and (2) a multicast group identifier to which the requestor belongs. The request is in multicast on a network address reserved for address resolution. All other nodes of the network monitor the reserved network address for address request messages. If a second node receiving the address request message has already allocated the requested multicast address, then the second node sends an acknowledgment message identifying (1) the already allocated in multicast address, and (2) the multicast group for which the address has been allocated. This acknowledgment is transmitted on the same reserved network address on which the address request was sent. The first node, monitoring the reserved network address, receives the acknowledgment message.

Abstract: The performance of video encoding is characterized both over the short term (e.g., based on the previous encoded frame) and over the long term (e.g., based on the previous n encoded frames). An encoding parameter (e.g., the global quantization level) is selected for the current frame based on the short-term and long-term performance characterizations and the current frame is encoded using that selected encoding parameter. In a preferred embodiment, the global quantization (Q) level is permitted to change for only certain (i.e., adjustable) frames. In addition, the global Q level for key frames is generated using special processing which tends to allow the key frames to be encoded using more bits.

Abstract: Methods and apparatuses for generating an image for display without creating a scaled bitmap. One or more bytes of digital data corresponding to portions of the image are received, scaled horizontally and vertically for display, and transmitted for display. In a preferred embodiment, encoded data corresponding to the image are decoded before being scaled for display. In an alternative preferred embodiment, analog signals corresponding to the image are generated, decoded, digitized, captured, compressed, and decompressed. The data displayed may be either the captured data or the decompressed data.

Abstract: Providing a directory of servers on a computer network with a directory server. According to a preferred embodiment, the directory server stores records of servers registered with the directory server and provides information about the registered servers to a browsing user of the network. The directory server allows an unregistered network server to register with the directory server.

Abstract: Two or more run-val mapping tables are selected to encode different subsets of video signals of a sequence of video signals. Each run-val mapping table is selected to map a particular set of run-val pairs to a corresponding set of run-val codes. Each run-val pair comprises a run and a val, the run corresponding to a length of a run of video signals having value zero and the val corresponding to a video signal having a non-zero value. Each run-val mapping table is used to generate a different part of an encoded bitstream for the sequence of video signals. The encoded bitstream is then decoded using the two or more selected run-val mapping tables. In a preferred embodiment, the selected run-val mapping tables are explicitly identified in the bitstream.