Multimedia Systems Design

Contents Introduction Multimedia elements Multimedia applications Multimedia systems architecture

Definitions and terminologies Introduction Multimedia: It is an ideal language for communication It is any integrated combination of text, art/images, sound, animation and video delivered by computer or other electronic or digitally manipulated means. A Multimedia system is characterized by computer controlled, integrated production, manipulation, presentation, storage and communication of independent information, which is encoded at least through a continuous and a discrete medium.

Definitions and terminologies Introduction If the user has control over the multimedia presentation then it becomes a non-linear and Interactive Multimedia presentation. Applications that involve more than conventional data types Multimedia is a computer-based interactive communication process that incorporates text, graphics, sound, animation, and video Hypertext: Text which contains links to other texts/web pages or other media. It allows a nonlinear way of navigation through the content.

Definitions and terminologies Introduction Hypermedia: Media having links to other media. All the web based applications and web sites are hypermedia based.

Introduction Applications Multimedia courseware Video/Audio conferencing Video-on-demand Virtual reality Digital Libraries Games Multimedia authoring CBT and WBT Digital video editing and production systems Electronic Newspapers/Magazines Games Home shopping Interactive TV

Introduction Advantages Increase in Retention rate Reduced production costs Ease of use and development Better way of communication Increase in cognition levels Can be used by a wide section of target users Utilizes the power of E-delivery platforms Convergence of computers, telecom, and TV Collaboration, virtual environments, and web casting

Challenges and complexity Introduction For example video conferencing requires a combination of technologies, including communications, high-resolution display systems, and storage and rapid dissemination of multidimensional objects consisting of text, image, voice, audio, and full-motion video components. The system will have to understand and know how to interpret and combine data elements of various types and be able to present it to the user in the desired mode set by the user. Groupware systems( to allow a number of office workers to work together on the same information) High bandwidth requirements.

Introduction Some more…. Multimedia meant a combination of text with document images New application areas include Medical applications Real-estate on-line video clips with property descriptions multimedia help and training material security systems for employee identification

Multimedia elements Elements Fascimile Document images Photographic images Geographic information systems maps Voice commands and voice synthesis Audio messages Video messages Full-motion stored and live video Holographic images fractals

Multimedia applications Document imaging Multimedia applications The fundamental concepts of storage, compression, and decompression and display technologies used for multimedia systems were developed for document image management. Document imaging makes it possible to store, retrieve, and manipulate very large volumes of drawings, documents and other graphical representations of data. A compression efficiency of over 20:1 is considered highly desirable for document images for most office systems. For high-resolution images, processing of the order of 10 pixels/ns is considered adequate for monochrome still images.

Image processing and Image recognition Multimedia applications Image processing involves image recognition, image enhancement, image synthesis, and image reconstruction. Image enhancement includes image calibration, real-time alignment, gray-scale normalization, RGB hue intensity adjustment, Color separation, Frame averaging. Image animation – scanned images can be displayed sequentially at controlled display speeds Image annotation – as a text file stored along with the image. The annotation is overlaid over the original image for display purposes. OCR is used for data entry by scanning typed or printed words in a form.

Image processing and Image recognition Multimedia applications Handwriting recognition – ability to recognize writer-independent continuous cursive handwriting accurately in real time. Two factors are important; strokes or shapes being entered and the velocity of input or the vectoring that is taking place. The strokes are parsed and processed by a shape recognizer that tries to determine the geometry and topology of the strokes. It attempts to compare it to existing shapes, such as predefined characters. Then the word may be checked against a dictionary. Non-textual image recognition: uses facial expressions, posture, and gestures which represent important input.

Full motion digital video applications Multimedia applications E-mail Business applications Training and manuals On-Line reference Video conferencing CD-ROM interactive training presentations demos Video karaoke Pay-per-view newspapers CD-ROM interactive games Interactive TV Games and Entertainment

Full motion digital video applications Multimedia applications Full-motion video clips should be sharable but should have only one sharable copy It should be possible to attach full-motion video clips to other documents such as memos, chapter text, presentations, and so on. Users should be able to take sections of a video clip and combine the sections with sections from other video clips to form their own new video clip All the normal features of a VCR metaphor, such as, rewind, FF,play and search etc should be available. Users should be able to search to the beginning of a specific scene, that is , the full-motion video clip should be indexed.

Full motion digital video applications Multimedia applications Users should be able to place their own indexing marks to locate segments in the video clip. It should be possible to view the same clip on a variety of display terminal types with varying resolution capabilities without the need for storing multiple copies in different formats. It should be possible for users to move and resize the window displaying the video clip. The users should be able to adjust the contrast and brightness of the video clip and also adjust the volume of the associated sound. Users should be able to suppress sound or mix sound from other sources. When video clips are spliced, then sound components are also spliced automatically.

Multimedia applications Electronic messaging Multimedia applications Message store and forward facility Message transfer agents to route messages to their final destinations across various nodes in a multilevel network. Message repositories (servers) where users may store them just as they would store documents in a filing cabinet Repositories for dense multimedia components such as images, video frames, audio messages and full-motion video clips. Ability for multiple electronic hypermedia messages to share the same multimedia components residing in various repositories on the enterprise network. Dynamic access and transaction managers to allow multiple users to access, edit, and print these multimedia messages.

Multimedia applications Electronic messaging Multimedia applications Local and global directories to locate users and servers across an enterprise network Automatic database sync of dynamic electronic messaging databases. Automatic protocol conversions and data format conversions Administrative tools to manage enterprise wide networks.

A universal multimedia application Multimedia applications A universal multimedia application An application that manipulates data types that can be combined in a document, displayed on a screen, or printed with no special manipulations that the user needs to perform Full motion video messages Viewer interactive live video Audio and video indexing

Multimedia systems architecture APPLICATIONS Graphical user Interface Multimedia extensions Multimedia driver support Operating system Software drivers System-Hardware (Multimedia-Enabled) Add-On multimedia devices and peripherals

Multimedia systems architecture High resolution graphics display VGA mixing VGA mixing with scaling Dual-buffered VGA mixing/scaling The IMA architectural framework It is based on defining interfaces to a multimedia interface bus. The multimedia interface bus would be the interface between systems and multimedia sources and would provide streaming I/O services, including filters and translators.

Network architecture for multimedia systems Multimedia systems architecture Network architecture for multimedia systems The network congestion can be attributed to a combination of the following causes Increased computing power of the desktop systems, workstations, and PC’s and their ability to run multiple applications concurrently. Business needs for more complex networks for a larger variety of data transmissions including voice, data, and video messages Increased traffic loads on existing backbone networks. Use of client server architectures for a wide range of applications Graphics-intensive applications Voice and video based multimedia applications that require large volumes of data storage. Number of users accessing the network

Network architecture for multimedia systems Multimedia systems architecture Network architecture for multimedia systems Task based multilevel networking – Higher class of service require more expensive components in the workstations as well as in the servers supporting the workstation applications. If we adjust the class of service to the specific requirements of the user it is task based multi-level networking High speed server to server links – duplication and replication Networking standards ATM, FDDI

A Course-on-Demand System On-line facilitator Courseware developer Network Multimedia Database Database server user

A Course-on-Demand System Metadata DB Authoring Tool Java Client Network Server DB Application Integration Software User Interface Media Server

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