MPEG

This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS HUB is implemented around a single PC with other subsystems making it very cost effective and unique of its kind. This realization will drastically reduce the total cost of Satellite based Education Networks as very low cost commercially available Satellite Interactive Terminals (SITs) complying to open standard could be used at remote locations. The system is successfully tested to work with a commercial SIT using a GEO satellite EDUSAT which is especially dedicated for satellite based e-Learning. The internal detail of the DVB-RCS Forward and Return Link Organization and how it manages the Satellite Interactive Terminals access to the satellite channel using MF-TDMA approach has been described.

MUVIS is a series of CBIR systems. The first one has been developed in late 90s to support indexing and retrieval in large image databases using visual and semantic features such as color, texture and shape. During recent years, MUVIS has been reformed to become a PC-based framework, which supports indexing, browsing and querying of various multimedia types such as audio, video, audio/video interlaced and several image formats. MUVIS system allows real-time audio and video capturing, encoding by last generation ...

Les systèmes de compression MPEG sont utilisés partout dans la vie courante. Le MPEG2 est utilisé dans tous les DVD, et même dans les transmissions d'images par satellite. Ce document vise à décrire simplement leurs principes de fonctionement et leurs méthodes. L'étude se fera sur le MPEG1, le MPEG2 et le MPEG4 qui sont les seuls formats MPEG à être réellement standardisés et utilisés.

Motion estimation is the process of determining motion vectors that describe the transformation from one 2D image to another; usually from adjacent frames in a video sequence. The motion vectors may relate to the whole image (global motion estimation) or specific parts, such as rectangular blocks, arbitrary shaped patches or even per pixel. Motion can be rotation and translation in all three dimensions and zoom. We are concerned with the "projected motion" of 3-D objects onto the 2-D plane of an imaging sensor. By motion n estimation, we mean the estimation of the displacement (or velocity) of image structures from one frame to another in a time sequence of 2-D images. Motion estimation is a video compression technique, which exploits temporal redundancy of the video sequence. Successive pictures in the motion video sequence tend to be highly correlated and consecutive video frames will be similar except for the change induced with the objects moving within the frames. This implies that the arithmetic difference between these pictures is small. In contrast, the objects that is in motion increase the arithmetic difference between the frames which in turn implies that more bits are required to encode the sequence. For this reason motion estimation technique is used to determine displacement of the object Motion Estimation and Compensation, The motion estimation creates a model by modifying one or more reference frames to match the current frame as closely as possible. The current frame is motion compensated by subtracting the model from the frame to produce a motion-compensated residual frame. This is coded and transmitted, along with the information required for the decoder to recreate the model (typically a set of motion vectors). At the same time, the encoded residual is decoded and added to the model to reconstruct a decoded copy of the current frame (which may not be identical to the original frame because of coding losses). This reconstructed frame is stored to be used as reference frame for further predictions.

This paper is a review of the block matching algorithms used for motion estimation in video compression. It implements and compares 7 different types of block matching algorithms that range from the very basic Exhaustive Search to the recent fast adaptive algorithms like Adaptive Rood Pattern Search. The algorithms that are evaluated in this paper are widely accepted by the video compressing community and have been used in implementing various standards, ranging from MPEG1 / H.261 to MPEG4 / H.263. The paper also presents a very brief introduction to the entire flow of video compression.

The new MPEG-4 standard provides a suite of functionalities under one standard: streaming multimedia content, good compression, and user interactivity. This paper provides an introduction to the use and internal mechanisms of these functions.

Recently, multimedia security is becoming more important with the continuous increase of digital communications on the internet. Moreover, special and reliable security is needed in many digital applications (such as video conferencing and medical imaging systems). The classical techniques for data security are not appropriate for the current multimedia usage. As a result, we need to develop new security protocols or adapt the available security protocols to be applicable for securing the multimedia applications. Encryption of MPEG-4 video streaming using AES has not been studied. In this paper, the performance of AES in encrypting MPEG-4 video is considered. The performance of AES is compared to two symmetric encryption techniques namely; RC4 and XOR. Three data types (text, audio and video) are used to test the effectiveness of AES in encrypting MPEG-4. Simulations showed the efficiency of the AES encryption technique in such application for the different data type given.

Lifelike talking faces for interactive services are an exciting new modality for man-machine interactions. Recent developments in speech synthesis and computer animation enable the real-time synthesis of faces that look and behave like real people, opening opportunities to make interactions with computers more like face-to-face conversations. This paper focuses on the technologies for creating lifelike talking heads, illustrating the two main approaches: model-based animations and sample-based animations. The traditional model-based approach uses three-dimensional wire-frame models, which can be animated from high-level parameters such as muscle actions, lip postures, and facial expressions.

A closed form solution for the output signal of a CMOS inverter driving an RLC transmission line is presented. This solution is based on the alpha power law for deep submicrometer technologies. Two figures of merit are presented that are useful for determining if a section of interconnect should be modeled as either an RLC or an RC impedance. The damping factor of a lumped RLC circuit is shown to be a useful figure of merit. The second useful figure of merit considered in this paper is the ratio of the rise time of the input signal at the driver of an interconnect line to the time of flight of the signals across the line. AS/X circuit simulations of an RLC transmission line and a five section RC Π circuit based on a 0.25 µm IBM CMOS technology are used to quantify and determine the relative accuracy of an RC model. One primary result of this study is evidence demonstrating that a range for the length of the interconnect exists for which inductance effects are prominent. Furthermore, it is shown that under certain conditions, inductance effects are negligible despite the length of the section of interconnect. DAC 98, San Francisco, California © 1998 ACM 1-58113-049-x/98/06 $3.50

We propose and analyze several strategies for performing timestamping of an MPEG-2 Transport Stream transmitted over a packet-switched network using the PCR-unaware encapsulation scheme, and analyze their e ect on the quality of the recovered clock at the MPEG-2 Systems decoder. When the timestamping scheme is based on a timer with a xed period, the PCR values in the packet stream may switch polarity deterministically, at a frequency determined by the timer period and the transport rate of the MPEG signal. This, in turn, can degrade the quality of the recovered clock at the receiver beyond acceptable limits. We consider three timestamping schemes for solving this problem: (i) selecting the deterministic timer period to avoid the phase di erence in PCR values altogether, (ii) netuning the deterministic timer period to maximize the frequency of PCR polarity changes, and (iii) selecting the timer period randomly to eliminate the deterministic PCR polarity changes. For the case of deterministic timer period, we derive the frequency of the PCR polarity changes as a function of the timer period and the transport rate, and use it to nd ranges of the timer period for acceptable quality of the recovered clock. We also analyze a random timestamping procedure based on a random telegraph process and obtain lower bounds on the rate of PCR polarity changes such that the recovered clock does not violate the PAL/NTSC clock speci cations. The analytical results are veri ed by simulations with both synthetic and actual MPEG-2 Transport Streams sent to an MPEG-2 Systems decoder.

This paper presents a new method to compute the prob-ability distribution of the delay of a combinational circuit and uses it obtain an estimate of the yield of the process that manufactures the circuit. We assume a simple delay model assigning a triangular distribution to the delay of a gate and ignore the logical function of the gate and the pin-to-pin delay. The method can handle tree-like circuits as well as circuits with reconvergent fanout in them. The chief advantage of this method over conventional Monte-Carlo simulation is that it is much faster while providing compa-rable quality. 1

The new MPEG-4 standard provides a suite of functionalities under one standard: streaming multimedia content, good compression, and user interactivity. This paper provides an introduction to the use and internal mechanisms of these functions.

We present a baseline MPEG-4 Advanced Video Coding (AVC) decoder based on the methodology of joint optimization of software and hardware. The software is first optimized with algorithm improvements for frame buffer management, boundary padding, content-aware inverse transform and context-based entropy decoding. The overall decoding throughput is further enhanced by pipelining the software and the dedicated hardware at macroblock level. The decoder is partitioned into the software and hardware modules according to the target frame rate and complexity profiles. The hardware acceleration modules include motion compensation, inverse transform and loop filtering. By comparing the optimized decoder with the committee reference decoder of Joint Video Team (JVT), the experimental results show improvement on the decoding throughput by 7 to 8 times. On an ARM966 board, the optimized software without hardware acceleration can achieve a decoding rate up to 5.9 frames per second (fps) for QCIF video source. The overall throughput is improved by another 27% to 7.4 fps on the average and up to 11.5 fps for slow motion video sequences. Finally, we provide a theoretical analysis of the ideal performance of the proposed decoder.

Predictive delay analysis is presented for a representative CMOS inverter with submicron device size using PREDICTMOS MOSFET model. As against SPICE, which adopts a time consuming numerical approach and relies more on empirical fitting of parameters for short channel devices, the predictive MOSFET model used is relatively simple and can be related to process and layout data with potential of estimation of the performance of a scaled design. The submicron CMOS inverter delay estimation under various loading and operative conditions have been compared against two benchmarks (a) Computer aided simulation with SPICE level 3 and (b) The analytical results of the Alpha Power Law based model. It is concluded that the PREDICTMOS model is potentially promising as a predictive analytic tool for submicron level design with transparency of device or circuit physics and an acceptable level of accuracy.

Efficient moving object tracking in cases of partial occlusion is a challenging task for the researchers in the fields of computer vision and video processing. In modern coding standards, like MPEG-4 and MPEG-7, the term of video objects is used to define moving objects in a video sequence. Automatic extraction of such objects is by no means trivial, and occlusion is one of most important problems. This paper reformulates one of the most popular deformable templates for shape modeling and object tracking, the Snakes, in a probabilistic manner, in order to include providence for partial occlusion of the moving objects. Experiments of object tracking in partial occlusion, in complex natural sequences, where temporal clutter, abrupt motion and external lighting changes have been carried out, showing the efficiency of the proposed approach.

In this paper we present the implementation of a WebGL Talking Head for iOS mobile devices (Apple iPhone and iPad). It works on standard MPEG-4 Facial Animation Parameters (FAPs) and speaks with the Italian version of FESTIVAL TTS. It is totally based on true real human data. The 3D kinematics information are used to create lips articulatory model and to drive directly the talking face, generating human facial movements. In the last year we developed the WebGL version of the avatar. WebGL, which is 3D graphic for the web, is currently supported in the major web browsers for desktop computers. No official support is given for mobile device main platforms yet, although the Firefox beta version enables it on android phones. Starting from iOS 5 WebGL is enabled only for the advertisement library class (which is intended for placing adbanners in applications). We were able to use this feature to visualize and animate our WebGL talking head.

Video Streaming has been a major application of today's IT enabled society both in professional & personal life of users. This has been used in Video Conferencing, E-education, closed room chatting and group discussions. Various organizations have developed and deployed their own clouds, and most of their conferences and meeting are held in the same clouds, for which various video codec are being used for real time streaming. MPEG is one of the formats which is used in real time streaming. Other format used for streaming is WMV.

In MPEG-4, the boundary blocks of reference video objects are padded by replicating the boundary samples towards the exterior. This scheme does not make use ofthe trend of pixel value variation 0ft.n present near object boundaries in padding the exterior pixels ofthe reference video object. Rather, it results in a break ofthis trend at the video object boundary, resulting in higher prediction errors for those pixel locations that are within the shape of the current block, but are outside that of the predicted block. In this paper, we propose a novel shape distortion adaptive hybrid padding technique to minimise prediction errors and improve compression ef3ciency. We show that this technique results in boundary block coding gains of up to 9% as compared to that ofthe MPEG-4 scheme.

Domain-specific ontologies have been developed by two different ISO Working Groups to standardize the semantics associated with the description of museum objects (CIDOC Conceptual Reference Model) and the description of multimedia content (MPEG-7) - but no single ontology or ...

In this paper, we present a case study for the design, programming and usage of a reconfigurable system-on-chip, MorphoSys, which is targeted at computation-intensive applications. This 2-million transistor design combines a reconfigurable array of cells with a RISC processor core and a high bandwidth memory interface. The system architecture, software tools including a scheduler for reconfigurable systems, and performance analysis (with impressive speedups) for target applications are described. RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC RC

At-speed testing of GHz processors using external testers may not be technically and economically feasible. Hence, there is an emerging need for low-cost, high-quality self-test methodologies, which can be used by processors to test themselves at-speed. Currently, Built-In Self-Test (BIST) is the primary self-test methodology available and is widely used for testing embedded memory cores. In this paper, we report our experiences in applying a commercial BIST methodology to two processor cores and analyze the problems associated with the current hardwarebased BIST methodologies. We propose a new software-based self-testing methodology for processors, which uses a software tester embedded in the processor memory as a vehicle for applying structural tests. The software tester consists of programs for test generation and test application. Prior to the test, structural tests are prepared for processor components in the form of selftest signatures. During the process of self-test, the test generation program expands the self-test signatures into test sets, and the test application program applies the tests to the components-under-test at the speed of the processor. Application of the novel softwarebased self-test method demonstrates its significant cost/fault coverage benefits and its ability to apply at-speed test while alleviating the need for high-speed testers.

Recent developments have given birth to H.264/AVC: a video coding standard offering better bandwidth to video quality ratios than previous standards (such as H.263, MPEG-2, MPEG-4, etc.), due to its improved inter-and intraprediction modes at the expense of higher computation complexity. It is expected that H.264/AVC will take over the digital video market, replacing the use of previous standards in most digital video applications. This creates an important need for heterogeneous video transcoding technologies from older standards to H.264. In this paper, we focus our attention on the interframe prediction, the most computationally intensive task involved in the heterogeneous video transcoding process. This paper presents a novel macroblock (MB) mode decision algorithm for interframe prediction based on data mining techniques to be used as part of a very low complexity heterogeneous video transcoder. The proposed approach is based on the hypothesis that MB coding mode decisions in H.264 video have a correlation with the distribution of the motion compensated residual in the decoded video. We use data mining tools to exploit the correlation and derive decision trees to classify the incoming decoded MBs into one of the several coding modes in H.264. The proposed approach reduces the H.264 MB mode computation process into a decision tree lookup with very low complexity. For general validation purposes, we apply our algorithm to two of the most important heterogeneous video transcoders: MPEG-2 to H.264 and H.263 to H.264. Our results show that the our data-mining based transcoding algorithm is able to maintain a good video quality while considerably reducing the computational complexity by 72% on average when applied in MPEG-2 to H.264 transcoders, and by 62% on average when applied in H.263 to H.264 transcoders. Finally, we conduct a comparative study with some of the most prominent fast interprediction methods for H.264 presented in the literature. Our results show that the proposed data mining-based approach achieves the best results for video transcoding applications.

The increase of IEEE 802.11's bandwidth led to a deployment of many multimedia applications over wireless networks. Nevertheless, these applications impose rigorous discipline constraints in QoS. To support the varying Quality-of-Service (QoS) requirements of emerging applications, the QoS-capable standard IEEE 802.11e has been specified. Digital video delivered over wired-to-wireless networks is expected to suffer quality degradation from packet loss. Video traffic is widely expected to account for a large portion of the traffic in future hybrid network, as multimedia applications are becoming increasingly popular. Initially this paper attempted to discover optimal parameters such as bandwidth utilization and packet size in order to enhance video stream quality and proposed New Adaptive Crosslayer Algorithm, a novel scheme for QoS enhancement for IEEE 802.11 wireless networks.

We present our system for personalized face and speech communication over the Internet. The overall system consists of three parts: The cloning of real human faces to use as the representative avatars, the Networked Virtual Environment System performing the basic tasks of network and device management, and the speech system, which includes a text-tospeech engine and a real-time phoneme extraction engine from natural speech. The combination of these three elements provides a system to allow real humans, represented by their virtual counterparts, to communicate with each other even when they are geographically remote. In addition to this, all elements present use MPEG-4 as a common communication and animation standard and were designed and tested on the Windows Operating System (OS). The paper presents the main aim of the work, the methodology and the resulting communication system.

Reduction in leakage power has become an important concern in low v oltage, low p o w er and high performance applications. In this paper, we use dual threshold technique to reduce leakage power by assigning high threshold voltage to some transistors in non-critical paths, and using lowthreshold transistors in critical paths. In order to achieve the best leakage power saving under target performance constraints, an algorithm is presented for selecting and assigning an optimal high threshold voltage. A general standby leakage current model which has been veri ed by HSPICE is used to estimate standby leakage power. Results show that dual threshold technique is good for power reduction during both standby and active modes. The standby leakage power savings for some ISCAS benchmarks can be more than 50.

We propose a video data embedding scheme in which the embedded signature data is reconstructed without knowing the original host video. The proposed method enables high rate of data embedding and is robust to motion compensated coding, such as MPEG-2. Embedding is based on texture masking and utilizes a multi-dimensional lattice structure for encoding signature information. Signature data is embedded in individual video frames using the block DCT. The embedded frames are then MPEG-2 coded. At the receiver, both the host and signature images are recovered from the embedded bit stream. We present examples of embedding image and video in video.

Design methodologies based on reuse of intellectual property (IP) components critically depend on techniques to protect IP ownership. IP protection is particularly challenging for hardware/software systems, where an IP core runs embedded software: both the software and the core are valuable IP that must be protected.

Delay and Peak Signal-to-Noise Ratio (PSNR). According to the simulation results, it is found that PDR and PSNR of the proposed method are better than that of aforementioned mapping approaches. However, the Average End-to-End Delay is a little bit larger than that of EDCA but less than that of Static approach. Hence, it can be concluded that the proposed method is appropriate for non real-time video streaming applications.

This paper discusses in-house designed and developed scale-down DVB-RCS hub along with the performance of the realized hub. This development is intended to support the Satellite Based e-Learning initiative in India. The scale-down DVB-RCS HUB is implemented around a single PC with other subsystems making it very cost effective and unique of its kind. This realization will drastically reduce the total cost of Satellite based Education Networks as very low cost commercially available Satellite Interactive Terminals (SITs) complying to open standard could be used at remote locations. The system is successfully tested to work with a commercial SIT using a GEO satellite EDUSAT which is especially dedicated for satellite based e-Learning. The internal detail of the DVB-RCS Forward and Return Link Organization and how it manages the Satellite Interactive Terminals access to the satellite channel using MF-TDMA approach has been described.

The decoding of the voice audio bit stream is an issue in terms of real-time transmission of high quality voice audio over the Internet. A stand-alone chip to perform decoding is a better solution over software approach. The MPEG audio compression provides high compression with minimal loss. This study describes a VHDL model of MPEG audio layer 1 decoder that perform concurrent processing while receiving voice quality audio input bit stream at a constant bit rate and simultaneously producing a stream of 8-bit monopole PCM samples at a constant sampling frequency in real time.

The requirement for a commonly accepted efficient mapping between multimedia metadata standards and semantic web-ontology standards is a major issue recognized by semantic multimedia research community. Though there have been several attempts to translate MPEG-7 audio descriptions to ontology languages there is very little literature that addresses issues associated with streaming video contents. In this paper we outline our plan to develop a methodology and the corresponding software implementation of mapping techniques of MPEG21 video items. The novelty of our effort lies in the fact that we address the complexity of video content’s metadata descriptions and its integration with the well recognized ontological standard through transparent mapping from original XML to RDF description. The validity of the proposed method and implementation detail will be verified against the MOSAICA semantic framework and its use cases.