Verizon Laboratories Inc.

Evert Basch

Arianne Michelle Lewis

Gonzalo R Arce

Liehua Xie

Steven Gringeri

Arnold M Michelson

Khaled Ali Shuaib

Allen H Levesque

Myung Jong Lee

Tarek Saadawi

The present invention relates to an improved method of de-jittering MPEG-2 and MPEG-4 data that is transmitted over a network. First, a network system jitter associated with periodic reference data packets is estimated. Then, the estimated system jitter is used to adjust clock-stamped reference values in the data packets before they are provided to the PLL for clock synchronization. The invented de-jittering method improves the PLL's ability to synchronize the MPEG data and provides for a better quality playback.

Method and system for de-jittering of transmitted MPEG-2 and MPEG-4 video

The present invention relates to a system and method for reliably transmitting data over wireless communication channels. The invented system comprises a transmitting device having an error control coding circuit and an interleaver circuit in communication with each other. The invented system also includes a receiving device having an error control decoding circuit and a de-interleaver circuit in communication with each other. The transmitting device and the receiving device communicate over a wireless communication channel . The error control coding circuit applies an error control code to the data before it is transmitted over the communication channel . The data is also interleaved prior to being transmitted. After transmission over the communication channel , the data is de-interleaved and any transmission errors are detected and corrected. The interleaving &ldquo;spreads out&rdquo; transmission errors over several data cells and thus makes the error control and correction process more effective and efficient.

System and method for reliable video transmission in wireless Asynchronous Transfer Mode networks with fading

The invention is a system for digital watermarking that operates on a conventional digital video stream to etch, on hand, and read, on the other hand, digital watermarks in the stream that do not visibly interfere with the video content. A system according to the invention operates on digital data that has been transformed into the spatial-frequency domain, using inter-block differences between spatial-frequency coefficients to encode the bits of a digital watermark. Using the principles of the invention, it is possible to encode multiple watermark bits between two adjacent blocks, thus providing higher watermark data rates relative to underlying video content.

Digital watermarking

A method of generating a authentication code (&ldquo;MAC&rdquo;) with improved error tolerance exhibits improved survivability against acceptable signal distortions such as recompression. A method of generating a message authentication code associated with an image includes receiving blocks of image coefficient data where each coefficient has an original value falling within a range of values. The range of values is divided into first and second regions both having allowed coefficient values, and an error tolerance buffer region formed between the first and second regions having disallowed coefficient values. The original values of DC coefficients from each block of the image coefficient data is mapped to a modified value contained in one of the first and second regions, but not contained in the error tolerance buffer region. A MAC is generated as a function of the most significant bits of the modified image coefficient values.

Message authentication code with improved error tolerance

According to the principles of the invention, there is provided a system for generating a message authentication code for a conventional digital video stream. The system operates on the rows and columns of block data for a video stream, and more specifically on histograms of DC coefficients from each row and column, to produce a compact code that is nonetheless descriptive of the underlying images in the video stream. The message authentication code can be reproduced from the images of a received video stream, and if desired, compared with a digital watermark embedded in the video stream in order to confirm the accuracy of the video content or identify the source of the video stream.

Message authentication code using image histograms

The present invention relates to a system and method for reliably transmitting Internet Protocol (IP) data packets over fading Internet communication channels. The invented system comprises a transmitting device having an interleaver circuit . The invented system also includes a receiving device having a de-interleaver circuit . The transmitting device and the receiving device communicate over a fading Internet communication channel . The transmitting device applies error control coding to the IP packets before they are transmitted over the fading Internet communication channel . The Interleaver circuit interleaves the IP data packets before transmitting them over the fading Internet channel . The receiving device receives the interleaved IP packets from the fading Internet channel . The de-interleaver circuit de-interleaves the received IP data packets. The receiving device also uses the error control coding to detect and correct any errors incurred during transmission. The interleaving &ldquo;spreads out&rdquo; transmission errors over several IP packets and thus makes the error control and correction process more effective and efficient.

System and method for reliable data transmission over fading internet communication channels

A system ( ) for watermarking digital data includes a watermark etching subsystem ( ) and a watermark extraction subsystem ( ). The watermark etching subsystem ( ) obtains a matrix of digital data values, selects windows including a plurality of data values from the matrix, specifies a parameter that indicates an acceptable amount of variation in the data values, and etches watermark bits in each window of data values using the specified parameter. The watermark extraction subsystem ( ) obtains a matrix of digital data values containing an etched watermark, selects windows comprising a plurality of data values from the matrix, and extracts watermark bits from each window of data values using the specified parameter.

Systems and methods for etching digital watermarks

A system and method are provided for analyzing and transmitting video over a switched network. According to an aspect of the invention, two phases are generally provided: an analysis phase performed before transmission of the video; and a transmission phase performed after analyzing the video stream. During the pre-transmission video analysis phase, the video stream is analyzed in order to determine the needed traffic control parameters, such as the peak cell rate, the sustained cell rate, and the maximum burst size. The goal of the analysis phase is to select a transmission traffic contract for the encoded video stream that will minimize the utilization of network resources and permit the quality of the video to be maintained. After the analysis phase, the transmission phase is performed to transmit the video over the network in accordance with the selected traffic control parameters. During the transmission phase, a model of the decoder buffer is kept at the source and is first pre-filled by transmitting data at the sustained cell rate. Thereafter, the video stream data is transmitted at the peak cell rate or the sustained cell rate depending on the availability of tokens.

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Stow, MA, United States of America

Evert Basch