Proceedings. IEEE International Conference on Multimedia and Expo

In this work, the instruction-level and function-level profile analyses of a MPEG-4 video encoder are performed to design a reconfigurable digital signal processor (DSP) architecture. According to the result from the instruction-level profile analysis, the proposed DSP architecture would be lined up with 5 arithmetic logic units (ALUs), 1 multiplier, and 2 load/store units. Such a line-up in the computation units would allow the proposed DSP architecture to have a better parallel processing capability and a higher hardware usage rate in realizing the MPEG-4 video encoder. The result from the function-level profile analysis reveals that the function of motion estimation requires the most computation power. Hence, the proposed DSP architecture reconfigures 4 ALUs and a multiplier to become a functional unit for high parallel processing of motion estimation. This hardware design of motion estimation is primarily dependent on the adders and multiplier of the proposed DSP architecture, plus a few control circuits to convert the computation units. Such arrangement would have less hardware cost than in conventional video processors with specialized functional units for motion estimation. Lastly benchmark analysis and comparison are done between the proposed DSP architecture and TI TMS320C64x architecture. In processing the MPEG-4 video encoder, the proposed DSP architecture is as much as 80% more efficient in computation than the TI TMS320C64x architecture.

E-health is greatly impacting on information distribution and availability within the health services, hospitals and to the public. Previous research has addressed the development of system architectures with the aim of integrating the distributed and heterogeneous medical information systems. Easing the difficulties in the sharing and management of multimedia medical data and the timely accessibility to these data are critical needs for health care providers. We have proposed a client-server agent that integrates and allows a portal to every permitted information system of the hospital that consists of picture archiving and communication systems (PACS), radiology information system (RIS) and hospital information system (HIS) via the intranet and the Internet. Our proposed agent enables remote access into the usually closed information system of the hospital and a server that manages all the multimedia medical data and allows for in-depth and complex search queries for content access and automatic creation of patient reports for distribution.

Sprite is an image collecting information of a video object through a video sequence. It can be used for efficient video coding, video summary, browsing, and editing. In this paper, three new techniques for sprite generation are proposed. Boundary matching and multiple sprites techniques can improve the subjective quality with refining the positions of the warped frames and generating more than one sprites. The frame skipping technique can skip redundant frames that contain only little new information when the camera revisits a scene several times to accelerate the sprite generation process. Experimental results show that these techniques can be employed independently and can improve the subjective quality as well as reduce the 47.68% - 17.22% runtime of sprite generation. They can be applied with any sprite generation algorithms.

Bandwidth-optimal open-loop near-video-on-demand streaming (NVOD) entails the optimal assignment of transmission rates to a large number of program segments. These are transmitted concurrently and repetitively at their assigned rates. At any given time in its viewing of the program, a client must record data belonging to a contiguous subsequence of the segments for subsequent display. Limited client recording rates and storage capacity affect the rate assignments. In practice, the concurrent streams must be time-multiplexed onto a single channel, and efficient operation of the client disk drive used to store received data until its viewing prevents fine-grain multiplexing. The bucket-interleaving multiplexing scheme presented in this paper guarantees that each segment is repeated in its entirety within any contiguous time interval of the appropriate length, and reduces the required client "rate-smoothing" RAM buffer by two orders of magnitude relative to pure earliest-deadline-first multiplexing.

Efficient and effective handling of video documents depends on the availability of indexes. Manual indexing is unfeasible for large video collections. Efficient, single modality based, video indexing methods have appeared in literature. Effective indexing, however, requires a multimodal approach in which either the most appropriate modality is selected or the different modalities are used in collaborative fashion. We present a framework for multimodal video indexing, which views a video document from the perspective of its author. The framework serves as a blueprint for a generic and flexible multimodal video indexing system, and generalizes different state-of-the-art video indexing methods. It furthermore forms the basis for categorizing these different methods.

Challenges in multimedia analysis are calling for the sharing of research efforts, while in practice collaboration is hindered by technical and proprietary issues. The Community of Multimedia Agents project (COMMA) attempts to solve this problem by creating an open environment for developing, testing, and prototyping multimedia content analysis and annotation methods. Each method is represented as an agent (an executable module) that can communicate with the other agents based on descriptors and description schemes in the coming MPEG-7 standard. This allows multimedia-processing agents developed by different organizations to operate and collaborate with each other, regardless of their programming languages and internal architecture. The researchers can compare the performance of agents and combine them to build more powerful and robust system prototypes. It can also serve as a learning environment for researchers and students to acquire and test cutting edge multimedia analysis algorithms. Through sharing of media agents, the Community can increase efficiency of research while protecting the intellectual property of the inventors.

Natural and structured audio representations can be characterized by the lack or presence of a model describing the sound, respectively; combination of the two approaches can lead to efficient and improved storage and transmission of both speech and music, mixing less efficient but general technologies with more compact and specialized models. Integration of natural audio tracks with structured sound and 3D spatial processing is a challenging effort, especially when the audio, scene requires high quality and precise synchronization with video and graphic information, as it is the case in professional multimedia and virtual reality frameworks. In this paper natural and structured sound are surveyed and a new player is presented, which supports all the mentioned technologies in a normative context.

Benchmarking of watermarking algorithms is a complicated task that requires examination of a set of mutually dependent performance factors (algorithm complexity, decoding/detection performance, and perceptual quality). This paper will focus on detection/decoding performance evaluation and try to summarize its basic principles. A methodology for deriving the corresponding performance metrics will also be provided.

In Pereira et al. (2002) we proposed a balanced multiple description coding (MDC) scheme based on the discrete wavelet transform (DWT). This MDC includes an efficient bit allocation procedure that dispatches the source image redundancy between different channels. The amount of redundancy is controlled according to the bit error rate of the different channels. Here, we propose to extend this approach for low bit rate video transmission. The proposed method uses the 3D scan-based DWT of Parisot et al. (2000) and involves scan-based MDC with rate or quality control.

This paper presents an application-driven architecture-design approach. VLIW architectures and instruction set simulation were chosen to fulfill multimedia domain requirements and to implement an efficient Hw-Sw co-design tool. Innovative approaches such as pipeline status modeling, simulation cache, and simulation oriented Hw description have been described. The performance of simulation tests for two validation case studies (TI TMS320C62x and ST200) are reported.