Lucent Technologies Inc.

At&t Bell Laboratories

Bell Telephone Laboratories

At+t Corp.

American Telephone & Telegraph Co., At&t Bell Laboratories

At&t Ipm Corp.

Nuggehally Sampath Jayant

Richard Vandervoort Cox

Nambirajan Seshadri

James David Johnston

Schuyler Reynier Quackenbush

Juin-Hwey Chen

Sean Matthew Dorward

Christine Irene Podilchuk

Jeffrey C Lagarias

Kevin A Shelby

Gordon F Bremer

Carl-Erik Wilhelm Sundberg

Kenneth David Ko

Robert J Safranek

Arnaud Eric Jacquin

Anthony James Grewe

Howard M Singer

Luke J Smithwick

Raymond Steele

Jialin Zhong

Kenneth Lane Thompson

Moshe Porat

Tsann-Shyong Liu

John G Apostolopoulos

Subhash Chandra Kak

Carolyn E Schmidt

Venkatasubbarao Ramamoorthy

Jose R De Marca

A tunable perceptual weighting filter is used in tandem codecs (coder/decoders). Specific filter parameters are advantageously tuned to provide improved performance in tandeming contexts. The parameters used are 10th order LPC (Linear Predictive Coding) predictor coefficients. The system employed uses Low-Delay Code Excited Linear Predictive codecs (LD-CELP).

Tunable perceptual weighting filter for tandem coders

The device and method according to the present invention permute the order of signals representing information intended for transmission over a communication medium. The signal ordering is permuted prior to or at the time of transmission over the communication medium such that when the information or data is transmitted in the permuted order, it is more tolerant to data corrupting defects, such as a faulty communications line, or events, such as an electromagnetic pulse, that exist or may occur during the communication process.

Method and apparatus for providing error-tolerant communication of

A method for simulating natural movement of a computer-generated synthesized talking head using an N-state Markov model. Initially, the number of states N is set representing N different positional orientations of the synthesized talking head. The transitions from each possible current position to each possible next position of the talking head are identified with a set of transitional probabilities in a range from zero to one. A uniformly distributed random number is generated and the state identified by the transition probabilities associated with the random number identifies the next position of the talking head. The synthesized talking head is rotated to that next position and remains there for a durational time period before transitioning to a next position which is probabilistically determined in like manner. To further simulate realistic head movement, the synthesized head may be programmed to remain in a particular state or position for an extended period of time at the end of a sentence of simulated speech.

Simulated natural movement of a computer-generated synthesized talking

The device and method according to the present invention permute the order of signals representing information intended for storage in a memory. The signal ordering is permuted prior to or at the time of storage in the memory such that when the information or data is stored in the permuted order, it is more tolerant to errors or defects that existed or may occur in the memory.

Method and apparatus for providing error-tolerant storage of information

The invention is an image transmitting method and system including receiving encoded images, decoding those images and post-processing the decoded images. The post-processing reduces visual artifacts, such as blocking artifacts and mosquito noise, through separate detection, mapping and smoothing operations while avoiding many of the complexities associated with existing techniques. In detecting blocking artifacts, the inventive method employs DCT-domain detection rather than edge detection in the pixel domain. Also, the interior of a detected block is updated based on the surrounding blocks without disturbing the surrounding blocks. In reducing mosquito noise, the inventive method smooths the non-edge pixels within blocks containing edge pixels rather than smoothing the edge pixels. Also, distortion-induced false edge pixels are distinguished from true edge pixels and heavily smoothed. The post-processing method and system is generally applicable to Block DCT based compression systems, either intrinsically or extrinsically.

Method and apparatus for post-processing images

The apparatus and method presented use a localized model-based approach to compress video image signals for applications such as video teleconferencing. Preferably, the apparatus and method use three-dimensional vector quantization (3D VQ), recent localized history of the image signals, and a pyramidal hierarchial encoding technique to compress the image signals.

Method and apparatus for image processing using model-based localized

An independent transport layer is used as an error correction mechanism in a method employing perceptual audio coding. The transport layer is characterized by the addition of information, via a transport header, to each of a succession of blocks of encoded program material which is independent of the information within its respective block of encoded program material. The transport header comprises information on the structure of the block. Thus, the transport header is easily separated from the digital representation of the program material and is independent of the content of the digital representation thereby providing for changing of the content of the digital representation without changing the transport layer.

Device and method for efficient utilization of allocated transmission

A digital audio broadcasting system incorporates a perceptual audio coder that encodes a digital audio signal for broadcast. A 'source label' is provided by controlling the perceptual audio coder in such a way that the number of coefficient samples, n, used in each transmission frame represents information about the source. For example, if the value of n is odd, then a binary '1' is transmitted, but if the value of n is even, then a binary '0' is transmitted. As a result, a low-bit rate 'source label' is transmitted over a number of frames. In a receiver, the source of the digital audio signal is identified by simply monitoring the value of n over the number of frames. More importantly, the value of n in each frame is required by a corresponding perceptual audio decoder, in the receiver, to correctly recover the digital audio signal. As a result, the 'source label' is inseparable from the encoded digital audio signal since any tampering of the value of n after transmission distorts not only the 'source label' but affects the recovery of the digital audio signal as well.

Hiding a source identifier within a signal

The present invention is a smart tray for an in-home audio player adapted to play pre-recorded music stored on a semiconductor music chip storage medium. Music chips are loaded into the smart tray which holds a predetermined number of chips and is inserted as part of the audio player. Each tray will have a low cost, low power microprocessor on board to handle routing and accessing of the music from an individual chip on the tray. For instance, the tray level microprocessor will be able to cue up a next song selection while a digital signal processor (DSP) within a base portion of the audio player finishes decoding the current selection. The smart tray minimizes music selection search times and allows the DSP to focus on processing the encoded music from the chips thereby minimizing housekeeping activities performed by the DSP and increasing efficiency. The smart tray allows for active music selections by the user so that the user can select a particular artist, song, music style, etc. with the touch of a button. This can be done since the music chips self-register content and music style to the smart tray upon power up. The audio player can be expanded by adding additional smart trays up to a predetermined limit.

Smart tray for audio player

An adaptive postfilter is used on the decoding side of tandem codecs (coder/decoders). Post-filter parameters are adapted using a backward synthesis filter. The parameters used are 10th order LPC (Linear Predictive Coding) predictor coefficients. The system employed uses Low-Delay Code Excited Linear Predictive codecs (LD-CELP).

Tunable post-filter for tandem coders

A method and apparatus for concurrent communication of analog information and digital information. In general terms, when the communication channel is viewed as a multi-dimensional space, the digital information signal is divided into symbols, and the symbols are mapped onto the signal space with a preset distance between them. The analog signal, generally limited in magnitude to less than the distance separating the symbols, is converted to component signals and added (i.e., vector addition) to the symbols. The sum signal is then transmitted to the receiver where the symbols are detected and subtracted from the received signal to yield the analog signal components. The transmitted analog signal is recreated from those components. Both half-duplex and full-duplex operation is available in accordance with the disclosure.

Simultaneous analog and digital communication

Compression of signals is achieved through a simple decision of whether or not to encode certain frequency bands; not how well to encode all of the frequency bands. Based on the input signal and on a preselected perceptual model, a 'just noticeable difference' (jnd) noise spectrum is computed. This spectrum is applied to a selector where it is used in the decision to select a chosen number of frequency bands of the input signal. The bands selected are the bands with the greatest energy relative to the jnd energy in the same band. Each of the selected bands is encoded and transmitted to the receiver. Both analog and digital realizations are presented.

Compression of signals for perceptual quality by selecting frequency

A system for and method of enhancing image/video signals to be decoded is disclosed. The system for and method of post-filtering uses, preferably, a temporal filter and a spatial filter, both of which are adaptive but neither is required to be adaptive. However, the system for and method of post-filtering may also be used with only an adaptive spatial post-filter. In this case, the performance is upper-bounded by the performance of systems using both the adaptive temporal and adaptive spatial post-filter.

Method of and system for enhancing distorted graphical information

A method of tailored error protection coding is disclosed. An illustrative coding method according to the present invention concerns encoding a first signal and a second signal to provide error protection for the signals, wherein the first signal requires greater error protection than the second signal. According to the method, the first signal is encoded with a first error protection code. The encoded first signal is then combined with the second signal. The combination of the encoded first signal and the second signal is further encoded with a second error protection code to generate a combined error protected signal, wherein the first signal is coded with both the first and second error protection codes. A second embodiment concerns the use of separate coders which apply different error protection codes to two signals. The two encoded signals are then combined into a single signal.

Tailored error protection

A geometric vector quantizer coding technique is illustrated in the context of a full motion video coder based on a three-dimensional sub-band framework. The original image data is decomposed into different spatial-temporal frequency bands and based on the data in each band, different quantization strategies are applied to the bands. The lowest spatial-temporal frequency band is coded using a traditional three-dimensional switched predictor and optimum scaler quantizer. The non-dominant sub-bands are coded using the vector quantization approach to efficiently encode the images while appropriately exploiting the sparse, highly structured nature of the data to design the codebooks. Variable resolution is achieved using these techniques and no training is needed to establish or maintain the codebook. A fast codebook search technique is provided for identifying the optimal codebook vector for representing a block of input data. Examples of two and three level geometric vector quantizers are also provided.

Growing community of inventors

Gillette, NJ, United States of America

Nuggehally Sampath Jayant