Abstract: In a transmitter, a standard stream of encoded multi-media data and uniform error correction data is transmitted through a first channel. The uniform error correction data provides substantially the same error correction for all portions of the encoded multimedia data. Simultaneously, additional unequal error correction data is generated for critical portions of the standard stream and not for other portions of the standard stream, and the additional error correct data is transmitted through a second channel. In a receiver, the additional error correct data is used to error correct just the critical portions of the standard stream, and then the uniform error correction data is used to error correct all the portions of the encoded multimedia data of the standard stream.

Abstract: Verifying a user includes: receiving a service request; generating a text based first dynamic password upon receiving the service request; converting the first dynamic password into sound information; transmitting the sound information to a user terminal over a communication network; receiving over the Internet a second dynamic password entered by the user based on the sound information, the second dynamic password being a text based password; comparing the first and second dynamic passwords for consistency; and indicating that verification is successful if the first and the second dynamic passwords are consistent.

Abstract: The present disclosure provides a method and a system for verifying identity of a user and a system for generating and maintaining verification codes. The method and the system use system-generated caller numbers as verification codes. When an application system needs to verify the identity of a user, the verification system generates a caller phone number and uses a communication switching system to place a call originating from the caller phone number to the user's phone. The user's phone has a caller ID display function to automatically display the caller number, which serves as a user identity verification code. The user provides the received caller number to the application system for user identity verification. No text messaging or other ways of communication is required. The method and the system can achieve reliable user identity verification. A centralized system may support multiple application systems for user identity verification.

Abstract: A method and a system for managing account transactions aim to effectively prevent account information from being compromised. The system generates a dynamic account number corresponding to a true account number of an account of a user and sends the dynamic account number to the user. The system stores the corresponding relationship between the true account number and the dynamic account number. The system conducts an account transaction requested by the user according to the dynamic account number supplied by the user and the corresponding relationship. The account can be a bank account, and the dynamic account number may be valid for a one-time use or set to expire after a certain period of time or a certain number of uses. The method and the system can make account transactions more reliable and safer, and effectively prevent user account information from malicious access.

Abstract: An apparatus, system and method are provided for adaptive flow control of layered streaming video over wireless local area networks (WLANs). In one aspect prioritised and adaptive transmission mechanisms are provided based on buffer fullness and discarding visually less important packets so that future visually more important packets can reach the decoder in time. In another aspect, aggregated control is provided for all video applications as well as separate control for each video application.

Abstract: A method of communication includes providing single layer content coded video frames (101-111, 202, 203, 205-208, 210-219). The method also includes selectively assigning each of the video frames to one of a plurality of levels. In addition, the method includes selectively transmitting some or all of the video frames in a prioritized manner based on bandwidth limitations. A video link (500) is also described.

Abstract: A system and method are provided for non-transmission specification fair air-time, NT-AirFair, allocation control by tracking the transmission time (308) consumed by each link to detect any increase and enforcing air -time allocation (309) based on the pattern of usage derived therefrom.

Abstract: A channel adaptive video transmission system and method. A system (10) is provided that includes: a variable length decoding system (VLD) (14) for generating header codes and discrete cosine transform (DCT) run length codes from the compressed video signal; a DCT codes marking system (16) for inserting markers into the DCT run length codes to define marked DCT coefficient segments; and a bit stream processing system (18) that determines whether to keep marked DCT coefficient segments based on current channel conditions.

Abstract: Network streams and a method for encapsulating media packets having data therein into the network streams. The network streams includes a base layer stream and an enhancement layer stream. Base-layer media packets are encapsulated into the network packets of the base layer stream, wherein each network packet of the base layer stream includes one, and no more than one, corresponding base-layer media packet. Enhancement-layer media packets are encapsulated into the network packets of the enhancement layer stream, wherein a first portion and a second remaining portion of any enhancement-layer media packet may be respectively included in successive network packets of the enhancement layer stream in order to have each network packet of the enhancement layer stream filled to a constant number of bits that does not exceed a maximum number of bits. The media packets are, but not limited to, video packets or audio packets.

Abstract: In a transmitter, a standard stream of encoded multi-media data and uniform error correction data is transmitted through a first channel. The uniform error correction data provides substantially the same error correction for all portions of the encoded multimedia data. Simultaneously, additional unequal error correction data is generated for critical portions of the standard stream and not for other portions of the standard stream, and the additional error correct data is transmitted through a second channel. In a receiver, the additional error correct data is used to error correct just the critical portions of the standard stream, and then the uniform error correction data is used to error correct all the portions of the encoded multimedia data of the standard stream.

Abstract: A system and method are disclosed that provide an advanced design of coded video packets using a resynchronization maker for video transmission applications. The resynchronization marker has a fixed ranged bit length within each video object plane or video frame and is cyclically updated video frame by video frame. This coded video packet structure allows decoders to automatically find the video object plane boundary without additional bit stream overhead. This has a particular advantage when a video object plane header is lost during transmission.

Abstract: A system and method is provided for combining advanced data partitioning and fine granularity scalability in the transmission of digital video signals. A partition unit 440 located in a base layer encoding unit 410 of a video encoder 400 partitions a base layer bit stream 310, 320 into a base layer first partition bit stream 310 and a base layer second partition bit stream 320. Each of the two base layer bit streams 310, 320 may be output directly or may be encoded before output. The two base layer bit streams 310, 320 may be encoded with a scalable encoder unit 442 or with a non-scalable encoder unit 444. Fine granularity scalability is improved by providing an extended base layer bit rate. The bit rate range for advanced data partitioning is also extended. The invention provides improved video coding efficiency, complexity scalability, and spatial scalability.

Abstract: A video coding system and method for coding an input frame in which the evolution of discrete cosine transform (DCT) coefficients is modeled as a Laplace-Markov process, the system comprising: a base layer processing system for generating a base layer reconstruction; an enhancement layer processing system for generating an enhancement layer reconstruction; and an entropy constrained scalar quantizer (ECSQ) system for descritizing a prediction residual between the input frame and an estimation theoretic (ET) prediction output; wherein the ECSQ system utilizes an ECSQ that comprises a uniform threshold quantizer with a deadzone size defined by the equation: ? ? ( ? , t * ) = 2 ? ( 1 1 - ? 2 ? ? t * - 1 ) , where ? ? ? ? ( ? , ? ) = ( ? ? - 1 ) ? exp ? { - ? ? [ d ? ( ? - ? ? ( ? ) ) - d ? ( - ? ) d ? ( ? - ? ? ( ? ) ) - d ? ( - ? ? ( ? ) ) ] } ? .

Abstract: A method and system for reducing power consumption in a wireless network by adjusting the transmit energy for each bit at the physical layer and the retry limit at the MAC layer. The method includes creating a look-up table containing optimal pairs of Nlim,Et for a plurality of different sets of transmission properties, wherein Nlim is a retry limit and Et is a transmit energy per bit; determing a set of transmission properties for a sequence of scalable video to be transmitted over the wireless network; accessing the look-up table to obtain the optimal pair of Nlim,Et, corresponding to the set of determined transmission properties; and transmitting the sequence of scalable video over the wireless network using the accessed optimal pair of Nlim,Et.

Abstract: The present invention relates to a method and system for estimating the quality of encoded video data without gaining access to the source data. The system is configured to decode compressed video data using an MPEG/H.263 decoder to produce decompressed video data. The decoded data is subject to a discrete cosine transform (DCT) to produce a set of DCT coefficients of the decompressed video data is determined to be intra-coded. Meanwhile, the quantization matrix including a quantizier step size for each block of the decompressed video data are extracted. Following this, statistical properties of the DCT coefficients are extracted from the decoded video. Then, an average quantization error for both AC and DC coefficients is determined using information regarding the quantization and the statistical properties. Finally, this estimated quantization error is used for in computing a peak signal to noise ratio (PSNR).

Abstract: A series of information portions are provided to a transmitter, the information portions have critical times when they need to be available to a receiver. The transmitter estimates whether the information portions can be transmitted by the transmitter in time to be made available to the receiver before the critical time. Then the transmitter only transmits the information to the receiver if it is estimated that the information portions will be transmitted in time to be made available to the receiver before the critical time.

Abstract: The present invention is directed to reduced B-frame decoding. According to the present invention, the number of transform coefficients in B-frames are reduced to produce reduced B-frames. Also, inverse scanning and inverse quantization is performed on the reduced B-frames. Further, an inverse transform is performed on the reduced B-frames. In one embodiment of the present invention, the reduced B-frames are produced by identifying blocks associated with the B-frames and selecting transform coefficients included in a predetermined area of the identified blocks.

Abstract: Data compressed according to a lossy DCT-based algorithm, such as the MPEG or MPEG2 algorithms, is decompressed according to a dynamically-selected set of DCT coefficients, with unused coefficients masked out. A macroblock of the data exhibiting little motion is decompressed with a small subset of DCT coefficients, while a macroblock exhibiting more motion is decompressed using a larger subset of DCT coefficients up the full set of DCT coefficients. Average computational complexity is thus kept low, enabling the use of inexpensive equipment, while degradation is minimized.

Abstract: A system and method are disclosed that provide an improved encoding scheme where input video is encoded into a base layer and a enhancement layer according to a fine-granular scalability coding to generate a plurality of equal priority descriptions, then the generated descriptions are decoded by a decoder. The plurality of equal priority partitions is comprised of partitions generated from the base and enhancement layers and a forward error correction (FEC) code according to predetermined criteria.

Abstract: Data compressed according to a lossy DCT-based algorithm, such as the MPEG or MPEG2 algorithms, is decompressed according to a dynamically-selected set of DCT coefficients, with unused coefficients masked out. A macroblock of the data exhibiting little motion is decompressed with a small subset of DCT coefficients, while a macroblock exhibiting more motion is decompressed using a larger subset of DCT coefficients up the full set of DCT coefficients. Average computational complexity is thus kept low, enabling the use of inexpensive equipment, while degradation is minimized.