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Animating human face presents interesting challenges because of its familiarity as the face is the part utilized to recognize individuals. This paper reviewed the approaches used in facial modeling and animation and described their strengths and weaknesses. Realistic face animation of computer graphic models of human faces can be hard to achieve as a result of the many details that should be approximated in producing realistic facial expressions. Many methods have been researched to create more and more accurate animations that can efficiently represent human faces. We described the techniques that have been utilized to produce realistic facial animation. In this survey, we roughly categorized the facial modeling and animation approach into the following classes: blendshape or shape interpolation, parameterizations, facial action coding system-based approaches, moving pictures experts group-4 facial animation, physics-based muscle modeling, performance driven facial animation, visual speech animation. [ABSTRACT FROM AUTHOR]

Due to technology advances in multimedia, larger storage spaces, large internet bandwidth and high-transmission speed are required for the transmission of videos. Video compression techniques play a vital role in reducing video size; therefore, smaller storage space and lower internet bandwidth are eventually required. In this paper, the EEG signal is used to modify the compression ratio of videos based on the interest of the viewer. This is performed by associating the compression ratio applied to the video with the degree of interest using a group of frames. This interest for a group of frames is measured using the EEG signal to demonstrate the viewer responses to videos. Statistical techniques applied to the EEG signal (such as peaks-over-threshold and time-of-peaks-over-thresholds) are used to extract the frames of interest. Peak signal-to-noise ratio (PSNR), Structural Similarity Index (SSIM) and Mean-Square Error (MSE) are used to compare the performance of the proposed technique with the MPEG-4 technique. The results show a reduction of 15 % in the video size compared with the MPEG-4 technique without deteriorating the quality of the videos

An embedded real-time indexing engine for live radio stations requires a high-speed parallel advanced audio coding (AAC) decoder architecture to decode hundreds of compressed audio streams broadcast in the digital radio mondiale band. Several AAC hardware core units must be integrated into a single chip and synchronized with a global controller to achieve such high performance. This paper proposes a new parallel AAC decoder architecture to address this challenge. The proposed architecture includes multiple AAC decoder core units, each of which achieves a speed-up by a factor of 2 compared with the existing AAC decoder core units while using optimal logic resources. The proposed architecture overcomes several challenges faced by existing architectures. The Huffman decoder module decodes one word per clock cycle regardless of word length, and a smaller lookup table size is achieved for the inverse quantization module. The inverse modified discrete cosine transform architecture is fully pipelined, and the resource sharing technique is used to reduce the logic area. An initial prototype is implemented on an FPGA platform.

Reliable video delivery is one of the most important requirements to satisfy end user needs. With the proliferation of multimedia technologies there is a growing demand for video multicast, particularly in challenging wireless environments. Effective video multicast services need to meet the conflicting goals of assured data rate and reliability. The most used IEEE standards (802.11a/b/g/n) do not ensure reliable multicasts since throughput remained primary focus of research in recent past. The IEEE 802.11aa remains the only standard that attempts to handle the unreliability issue with multicasting. However, the block acknowledgement scheme of the IEEE 802.11aa standard suffers from scalability issue. As the number of receivers increases, the number of acknowledgement packets increases proportionally. This increasing acknowledgement storm eventually causes a decrease in the average peak signal-to-noise ratio (PSNR) of the video frames. Therefore, in order to overwhelm the scalability limitation of the IEEE 802.11aa block acknowledgment scheme, this paper proposes a modified block acknowledgment scheme for video multicast. Our scheme considers the impact of the loss of different frames on video quality under Moving Picture Expert Group 4 (MPEG-4) and H.264 video coding. We provide a Markov chain model and numerical analysis of our proposed protocol. Simulation results indicate that proposed scheme performs well in terms of PSNR. [ABSTRACT FROM AUTHOR]

In this paper, we introduce our method to facilitate the process of creating an MPEG-4 compliant face model based on a simple 3D mesh. The presented method is semi-automatic, and the user needs to choose several points on the model as a preprocessing step. We use a cage based deformation technique to approximate an input model with a generic one which already contains the required MPEG-4 parameters. In the paper, we also show how the cage can be constructed to surround the model completely and be close enough to the head to get better deformation results. After these steps, the resulting model can be used in any MPEG-4 based facial animation player. [ABSTRACT FROM AUTHOR]

Lip synchronization of 3D face model is now being used in a multitude of important fields. It brings a more human, social and dramatic reality to computer games, films and interactive multimedia, and is growing in use and importance. High level of realism can be used in demanding applications such as computer games and cinema. Authoring lip syncing with complex and subtle expressions is still difficult and fraught with problems in terms of realism. This research proposed a lip syncing method of realistic expressive 3D face model. Animated lips requires a 3D face model capable of representing the myriad shapes the human face experiences during speech and a method to produce the correct lip shape at the correct time. The paper presented a 3D face model designed to support lip syncing that align with input audio file. It deforms using Raised Cosine Deformation (RCD) function that is grafted onto the input facial geometry. The face model was based on MPEG-4 Facial Animation (FA) Standard. This paper proposed a method to animate the 3D face model over time to create animated lip syncing using a canonical set of visemes for all pairwise combinations of a reduced phoneme set called ProPhone. The proposed research integrated emotions by the consideration of Ekman model and Plutchik’s wheel with emotive eye movements by implementing Emotional Eye Movements Markup Language (EEMML) to produce realistic 3D face model. [ABSTRACT FROM AUTHOR]

Making realistic facial animation is one of the most challenging research topics in facial animation field because producing realistic photo and sentimental virtual characters require a combination of face modeling, animating, and rendering. Techniques that commonly used for facial animation are in need of naturalism. The most popular expression coding systems are FACS (Facial Action Coding System) and MPEG-4 (Moving Pictures Experts Group-4) Facial animation models. FACS is a landmark technique that enables remarkable improvements in making realistic facial animations. Where MPEG-4 for Facial Animation provides a standard way of encoding various facial actions by defining parameters. defines various parameters for a talking face in a standardized way. In this paper, we made a review on how to achieve realistic facial animation, focusing on the applications and limitations of the FACS comparing to MPEG-4 facial animation. The review inferred that FACS helps animators to represent and build realistic facial expressions by configuring all possible facial animation units of the human face. [ABSTRACT FROM AUTHOR]

Digital Watermarking is an important method of protecting the intellectual property and copyright of the digital media. In this paper, a new digital video watermarking algorithm Color Watermark Embedding Algorithm (CWEA) is proposed. CWEA has two important parts. First, YCbCr color format is used to insert the variable size watermark. Second, embedding of detail coefficients of LUMINANCE (Y-luminance) of the watermark into the detail coefficients of CHROMINANCE (Cb and Cr- chrominance) of identical frames (I-Frames) of digital video. Data is inserted into the detail coefficients in an adaptive manner based on the energy of high frequency. A number of tests have been executed for many video-frame manipulations and attacks. All these tests are also performed on CWEA and it provides good results. In this paper, non-blind and semi-blind watermarking systems are used where the non-blind watermarking mechanism has been proved to be robust, imperceptible and efficient to protect the copyright of H.264 and MPEG-4 coded video within the video retrieval system. [ABSTRACT FROM AUTHOR]

In this paper, a novel double MPEG-4 compression detection method is proposed based on block artifact measurement. According to the properties of recompressed frames, an adaptive post-filtering technique is used to measure the strength of block artifacts in decompression domain. Then, the measurement of block artifacts is combined with the Variation of Prediction Footprint (VPF) using an adjustive parameter for each frame. This combination aims to enhance the robustness of the measurement sequence against degradations caused by lossy recompression. Finally, a temporal periodic analysis method is applied to the measurement sequence to detect double compression and estimate the size of the original Group of Pictures (GOP). The performance of the proposed method is evaluated on several public-available standard videos compared with several existing algorithms. Experimental results demonstrate the proposed method has better detection capability and estimates original GOP structures more accurately. Besides, the proposed method is more robust against different transcoding processes. [ABSTRACT FROM AUTHOR]

IEEE 802.11e has been introduced to support quality of service (QoS) in WLANs by allocating different traffics to four access categories. Cross-layer design is a method to improve the transmission quality of multimedia over wireless networks. However, when the fragmented packets of a single frame are allocated to different AC queues, out-of-order delivery may occur. Then the receiving node requires more buffer space to absorb the out-of-order packets. Therefore, even with a significance classification mechanism, the quality of the video transmission may still be limited due to the occurrence of out-of-order delivery and the transmission of information that becomes useless to the receiver. Therefore, this work developed a novel mapping mechanism (NMM) to improving the quality of MPEG-4 video delivery over IEEE 802.11e networks. The NMM considers the action that was taken on packet of the video frame that had been previously transmitted to resolve the out-of-order delivery by allocating them to the same AC queue as the previously process if possible. Furthermore, the proposed mechanism NMM takes more aggressive scheme to protect more important frame packets from being dropped. In order to evaluate the quality of MPEG-4 video delivery over IEEE 802.11e networks by the proposed mechanism, this work adopted two evaluation metrics, which is called Peak to Signal Noise Ratio (PSNR) and the ratio of frames loss. The simulation results demonstrate that, in terms of both PSNR and the ratio of frames loss, the proposed scheme outperforms exiting schemes such as EDCA (Enhanced Distributed Channel Access) and adaptive mapping. [ABSTRACT FROM AUTHOR]

In this study, we develop a hierarchical packet pre-dropping (HPPD) approach that exploits different methods to process intra-coded (I)/predictive-coded (P)/bidirectionally predictive-coded (B) video frame packets to improve the video transmission quality in heavily loaded IEEE 802.11e wireless local area networks (WLANs). It is not easy to transmit packets in WLANs with a heavy traffic load. Efficient transmission of video packets is important for improving the quality of video transmission. If the network becomes congested, important packets may be dropped. Further, video packets tend to be affected considerably more than data packets. Therefore, controlling the traffic of insignificant packets to avoid the transmission of useless data can improve the quality of video transmission. On the basis of this concept, in this paper, we propose a strategy that is different from the approaches proposed in earlier studies. First, identification of the dependence of video frames in a group of pictures (GOP) can prevent the transmission of useless data. Thus, the transmission channel resources are economized by avoiding the transmission of undecodable video frames. Second, in heavily loaded WLANs, it is not sufficient to utilize the queues to transmit important video frame packets. HPPD adopts the method of an aggressive drop of unimportant packets to retain the transmission channel resources for important video packets. Experiments have demonstrated that in heavily loaded WLANs, the Peak Signal to Noise Ratio (PSNR) for the case when the HPPD mechanism is adopted is better than that when enhanced distributed channel access (EDCA), adaptive mapping, or a novel mapping mechanism is used. [ABSTRACT FROM AUTHOR]