We review error resilience techniques for real-time video transport over unreliable networks. Topics covered include an introduction to today's protocol and network environments and their characteristics, encoder error resilience tools, decoder error concealment techniques, as well as techniques that require cooperation between encoder, decoder, and the network. We provide a review of general principles of these techniques as well as specific implementations adopted by the H.263 and MPEG-4 video coding standards. The majority of the article is devoted to the techniques developed for block-based hybrid coders using motion-compensated prediction and transform coding. A separate section covers error resilience techniques for shape coding in MPEG-4.

Error resilient video coding techniques

A display apparatus includes an image processor which processes an image to display an image content; a display unit which displays thereon an image content that is processed by the image processor; and a controller which displays a user interface (UI) menu including a plurality of UI items to search the image content, as one of a two-dimensional (2D) layout by which the plurality of UI items are arranged in a 2D manner, and a three-dimensional (3D) layout by which the plurality of UI items are arranged in a 3D manner , and changes displaying the one of the layouts to display the other of the layouts according to a user's command while maintaining a continuity of the arrangement of the plurality of UI items. Accordingly, search for an image content can be efficiently performed by using a UI menu.

Display apparatus and control method thereof

A telecommunication and multimedia management apparatus and method that supports voice and other media communications and that enables users to: (i) participate in multiple conversation modes, including live phone calls, conference calls, instant voice messaging or tactical communications; (ii) review the messages of conversations in either a live mode or a time-shifted mode and to seamlessly transition back and forth between the two modes; (iii) participate in multiple conversations either concurrently or simultaneously; (iv) archive the messages of conversations for later review or processing; and (v) persistently store media either created or received on the communication devices of users. The latter feature enables users to generate or review media when either disconnected from the network or network conditions are poor and to optimize the delivery of media over the network based on network conditions and the intention of the users participating in conversations.

Telecommunication and multimedia management method and apparatus

A monitoring device configured to be attached to the ear of a person includes a base, an earbud housing extending outwardly from the base that is configured to be positioned within an ear of a subject, and a cover surrounding the earbud housing. The base includes a speaker, an optical emitter, and an optical detector. The cover includes light transmissive material that is in optical communication with the optical emitter and the optical detector and serves as a light guide to deliver light from the optical emitter into the ear canal of the subject wearing the device at one or more predetermined locations and to collect light external to the earbud housing and deliver the collected light to the optical detector.

Light-guiding devices and monitoring devices incorporating same

An encryption arrangement for multiple encryption of television programs. A system according to embodiments of the present invention multiple encrypts only a portion of the data required for full presentation of a television program to permit coexistence of multiple conditional access encryption systems associated with multiple manufacturer's set-top boxes within a single system. In one embodiment, only critical packets such as those carrying a payload incorporating packetized elementary stream header information is encrypted. By only encrypting a portion of the program, dramatically less bandwidth is consumed than the alternative of multiple encryption of all program data, thus permitting a larger number of programs to be carried over the same bandwidth while permitting coexistence of multiple conditional access systems in a single cable television system.

Critical packet partial encryption

In this paper, we develop an approach toward joint source-channel coding for motion-compensated DCT-based scalable video coding and transmission. A framework for the optimal selection of the source and channel coding rates over all scalable layers is presented such that the overall distortion is minimized. The algorithm utilizes universal rate distortion characteristics which are obtained experimentally and show the sensitivity of the source encoder and decoder to channel errors. The proposed algorithm allocates the available bit rate between scalable layers and, within each layer, between source and channel coding. We present the results of this rate allocation algorithm for video transmission over a wireless channel using the H.263 Version 2 signal-to-noise ratio (SNR) scalable codec for source coding and rate-compatible punctured convolutional (RCPC) codes for channel coding. We discuss the performance of the algorithm with respect to the channel conditions, coding methodologies, layer rates, and number of layers.

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Joint source-channel coding for motion-compensated DCT-based SNR scalable video

A group of "servant" devices (104, 108) each downloads (306) a media presentation and renders (308) the presentation to a local user (102, 106). However, a "master" device (104, 108, 110) directs (404) the servants (104, 108) as to which chunks to download and when to render (408) the presentation. In this way, the master (104, 108, 110) keeps the presentations on the separate servants (104, 108) in synchrony. The master (104, 108, 110) uses status information (406) from the servants (104, 108) to coordinate the downloads. If, for example, one servant (104, 108) is having a difficult time keeping up with the presentation, then the master (104, 108, 110) may choose to direct that servant (104, 108) to download a reduced-resolution version of the presentation (which requires less bandwidth to download). If the user (102, 106) of one of the servant devices (104, 108) enters a playback command, then that command is not executed locally but is instead sent (310) to the master device (104, 108, 110) which in turn sends (412) the command to all of the servants (104, 108) so that they may execute (308) the playback command in synchrony.

Coordinating media presentations among peer devices

A method and device for detecting errors in a digital video signal comprising a sequence of image frames, each image frame comprising a sequence of image slices, each image slice comprising a sequence of macroblocks and each macroblock comprising a plurality of pixels. A macroblock decoder includes an error detection unit that operates to calculate an error metric between pixel values on at least part of the boundary between a current macroblock and one or more adjoining macroblocks and to label the current macroblock as suspicious if the error metric is greater than a threshold level. The threshold level is adjusted according to a weighted average error metric from one or more previous image frames. Suspicious macroblocks and subsequent inter-coded macroblocks may be regenerated according to a concealment strategy if a syntax error is found within the current image slice.

Method and device for suspecting errors and recovering macroblock data in video coding

A heart rate sensing system ( 300 ) includes a light source ( 112, 310, 1008, 1110 ) a light detector ( 114, 1010, 1112 ) and a pressure sensor ( 116, 1012, 1114 ) held by a compressible comformable resilient pad ( 110, 1006, 1108 ) against a wearers body ( 202 ). A signal from the pressure sensor is used to alter the amplitude of a signal detected by the light source in order to reduce motion artifacts. The system can be incorporated into an article, such as an ear cuff ( 100 ), an audio headset ( 1000 ) or a set of headphones ( 1100 ), that is suitable for use by an active user.

Method and apparatus for robust heart rate sensing

A fast video encoder (100) and method (500) for selecting (809) Inter macro-block mode or intra macro-block mode is provided. The method can include estimating (502) a rate-distortion cost (801) of a plurality of predictors (203) for coding a video (201), selecting (504) a predictive coding mode for the video based on a minimization of the rate-distortion cost, and coding (505) the image using a predictive mode associated with the minimum rate-distortion cost. The rate-distortion cost can be estimated across Intra macro-block modes and Inter macro-block modes for reducing a computational complexity. Rate-Distortion costs can be terminated early (524) based on statistical information (522) across a plurality of predictors for increasing an encoding speed. A fast estimation of the rate-distortion cost associated with the Intra macro-block mode for making inter/intra macro-block mode decision in a video coding system by exploiting the coding statistics across prediction modes is presented.

Faisal Ishtiaq

Papers

Joint source-channel coding for motion-compensated DCT-based SNR scalable video

Coordinating media presentations among peer devices

Method and device for suspecting errors and recovering macroblock data in video coding

Method and apparatus for robust heart rate sensing

Apparatus and method for fast intra/inter macro-block mode decision for video encoding