摘要:
STM traffic, e.g. voice and video telephony (VT), as well as packet mode (e.g. ATM) traffic, e.g. broadcast digital video, interactive television, and data, are transmitted via a multiple access broadband fiber/coaxial cable network. Customer premises equipment (CPE) at stations, and a bandwidth controller, which may be at a head end or central office, with which all stations communicate, work together to adapt to the changing demands of the traffic mix, and efficiently allocate bandwidth to a variety of bursty and isochronous traffic sources. The bandwidth allocation defines two types of time slots, STM and ATM, and divides each frame into two corresponding STM and ATM regions. The boundary between the regions can be changed dynamically. A contention access signaling channel is provided in the STM region, for call control and set-up requests. Within the STM region, the time slots can be of variable length and be allocated on a per call basis; the length of the time slots is proportional to the bandwidth requirement of STM calls. Within the ATM region, the time slots are of fixed length, each capable of accommodating one ATM cell. Further, the fixed length ATM time slots may be reserved for a particular user for the duration of a call, or may be shared through a contention process. At least one contention ATM time slot is always made available for signaling messages related to ATM call control and set-up requests. The downstream time frame is structured in a similar manner, but includes an additional MAP field to transmit to the stations ATM time slot allocation and status information for time slots in the upstream channel.
摘要:
A head-end dynamically allocates bandwidth of a communications channel as a function of the type of communications traffic. In particular, the head-end communicates to subscriber stations via a broadband cable network using an access protocol, which is modified to provide a variable number of mini-slots and a variable number of data slots in each frame. Each mini-slot is used to request assignment of a data slot(s) to subscriber stations for the communication of information and, also, as a vehicle to resolve contention between subscriber stations. The head-end dynamically adjusts the number of mini-slots over a period time as a function of the type of communications traffic, e.g., bursty and isochronous traffic sources. Any variation in the number of mini-slots concomitantly effects the number of data slots available to communicate information. For example, less mini-slots provides more data slots. As a result, the dynamic adjustment of the number of mini-slots allows the head-end to more efficiently allocate bandwidth on the communications channel.
摘要:
A protocol for handling multiple access on broadband communication networks, e.g., fiber/coax networks and wireless networks, supports both continuous bit rate (CBR) and variable bit rate (VBR) traffic representing voice, video telephony, interactive television, and data. The invention is carried out both in customer premise equipment (CPE) at stations, and in a common controller with which all stations communicate. A medium access control (MAC) processor provided in each of the stations and in the common controller divides the time domain for a given RF channel into a series of successive frames, each having a plurality of time slots. Because of the architecture of the communication network, individual stations do not communicate directly with each other, but can receive broadcast messages indicating the status of each time slot, which messages are generated in the common controller and transmitted in a downstream channel. When a station desires to transmit information in the upstream direction, it inserts the information into an available time slot, with availability being determined in accordance with time slot status. Depending upon the type of traffic being originated, a station can indicate to the common controller a need for continued use of the “same” time slot in successive frames. This permits a station, such as a station requiring a CBR connection, to avoid having to contend repeatedly for continued access to the transmission network. In the case of a wireless communication network, the invention is carried out both in mobile stations, and in a base station which acts as a common controller and with which all mobile stations communicate.
摘要:
An image depth information refreshing method applied to an image depth information refreshing device is disclosed. The image depth information refreshing device includes a storage unit and an arithmetic logic unit. The storage unit stores a previous depth diagram corresponding to a previous image. The image depth information refreshing method includes the following steps. The arithmetic logic unit divides a current image captured by an image capturing unit into multiple image blocks. The arithmetic logic unit calculates a depth reference value of each image block according to the previous depth diagram, and determines a weight of each image block according to the depth reference values. The arithmetic logic unit determines a refreshing frequency of each image block according to the weights. The arithmetic logic unit respectively refreshes the image block according to the refreshing frequencies of the image blocks, and generates a current depth diagram corresponding to the current image.
摘要:
A system and method for improving the handling, management, and retention of particular accounts. An allowable calling number list is generated via a suitable mechanism such as a call center. The allowable calling number list is utilized by telephone number management server to manage inbound call access to suspended accounts. Account representatives are given access to the suspended numbers. Additionally, certain emergency inbound calls may be permitted from select numbers.
摘要:
A display control apparatus and a display control method are disclosed. The display control apparatus comprises a recognition circuit and a mapping circuit. The recognition circuit recognizes a head position and a control point position of an operator. The mapping circuit dynamically adjusts the operating boundary according to the head position, the control point position and a display boundary, and calculates the cursor position on a display according to the control point position, the operating boundary and the display boundary, wherein the cursor position remains on a imagine line passing through the head position and the control point position.
摘要:
An image encoding system and an image encoding method are provided. The image encoding system comprises a relation computing unit and an embedded unit. The relation computing unit receives a plurality of view-angle images each comprising a plurality of pixels, and calculates a relative relationship between pixels according to their colors and locations of the pixels to generate a plurality of encoding images. The embedded unit respectively embeds the encoding images in the view-angle images to generate a plurality of embedded images.
摘要:
A display control apparatus and a display control method are disclosed. The display control apparatus comprises a recognition circuit and a mapping circuit. The recognition circuit recognizes a head position and a control point position of an operator. The mapping circuit dynamically adjusts the operating boundary according to the head position, the control point position and a display boundary, and calculates the cursor position on a display according to the control point position, the operating boundary and the display boundary, wherein the cursor position remains on a imagine line passing through the head position and the control point position.
摘要:
An information access system and method is presented which allows a network-connected user to view information content on the network according to the electronic proximity to the user, and other factors. Information content is discriminated according to the type of that information, and physical channels available to access that information. The illustrated information types can include infoid, local content and remote content.
摘要:
A focus-adjusting apparatus and platform of an imaging device includes a base, a holding device, a gear set, an imaging device and a stepping motor. The imaging device is disposed on the base during the focus-adjusting process and can be removed from the base after the focus-adjusting process. The stepping motor adjusts the focus of the imaging device and an image-processing unit calculates and records the modulation transfer function of the imaging device. The focus of the imaging device is set to a value with which the imaging device has the optimum modulation transfer function.