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The term ‘multimedia’ essentially implies ‘means of communication through multiple media’. From the earliest times, man has attempted to communicate his ideas through various means, like gestures, sounds, paintings, writings, etc. The multiple sense organs of man also enable him to comprehend and support such kind of multi-modal communications. In the real world, the non-textual form of communication like, cave paintings was used much before the written form originated. In the computing world, however, the trend has been just the reverse; text was the predominant form of communication over most of the earlier part of computing history. Only in the last 20 years did non-textual forms gain significance. Dealing with text through computers was much easier than dealing with non-textual media, like pictures or sound. In recent times, many technical barriers have been overcome and practical problems solved. this book on Principles of Multimedia gives an insight into these solutions and highlights the landmarks achieved, a theoretical treatise of man’s endeavour for communicating through multiple means in the digital domain. By multiple means we now imply the following media: text, image, graphics, audio, video and animation, all in the digital form. Added to the above is an important aspect of multimedia that distinguishes it from television and movies—that of interactivity. At the basis level, this lets the viewer interact with a presentation and decide how he or she wants to view it, e.g. jump from the opening scene to a specific section, instead of passively watching it from beginning to end. At a more advanced level, interactivity lets the user change the normal course of action within the presentation by performing certain pre-defined events. Good examples of such interactivity are computer games and simulation packages like aircraft training simulation. A ‘multimedia presentation’ is a ‘digital show’ which uses most or all of these components in an integrated way to communicate some idea to the target audience. The advantage of such a presentation lies in the fact that one is allowed with only specific portions of the subject instead of presenting the entire view. The second objective of this book is to provide a comprehensive view of most of the important and relevant aspects about the subject, written in a way so that it might be used as a textbook or reference book in educational institutions.

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It is well known that the capabilities of our computers are increasing in leaps and bounds. Keeping pace with this, the functionalities of multimedia hardware and software are also improving day by day. In such a scenario, students, researchers and professionals working in this field need to keep their knowledge updated. In the commercial arena too, the markets are flooded with gadgets with newer functionalities and improved features. People often come across a variety of terms in their day to day lives without understanding fully what they stand for. A few examples are: 5.1 channels surround sound, support for ATRAC audio formats by portable CD players, LCD televisions, digital Audio Broadcasting (DAB), Digital Data Storage (DDS), Digital Audio Tape (DAT), mp3PRO, iTunes and iPod, Digital Dolby, Digital Theatre Systems (DTS), Betacam, VHS, camcorder, laserdisc, DivX, MP4, BitTorrent format for exchanging media files on the Internet, the Super Audio CD, the DVD+RW and the DVD-RW standards, virtual reality, double layered double sided DVDs and video conferencing only to name a few. A third objective of this book is to provide the reader with an uptodate knowledge of the recent advances in this field, which is more often seen in magazines and the Web than in textbooks. Attempts have been made to bring details about the state of the art in each field in an easy-to-understand manner.

WHO WILL BENEFIT FROM THIS BOOK? As mentioned before, this book is meant the students for, both at the graduate and the postgraduate levels, who have multimedia related subjects as part of their curricula. This would include the technical colleges and institutions having streams like computer, communication, electronics, information technology. The book would also be useful for short certificate or diploma courses in subjects like image processing, audio/video processing, graphics and animation, network basics, design and development to present his/her ideas in a variety of forms and ways which increase the comprehension level and retentivity of the subject matter in the viewer’s mind. This makes it an important tool in education. other possible uses of multimedia include home entertainment, industrial training, information kiosks, corporate presentations, computer aided design applications, video conferencing and telemedicine only to name a few.

OBJECTIVE OF THIS BOOK With the increase in the processing powers of computers and decrease in the costs of hardware and software, there has been a definite trend in utilizing the advantages of digital multimedia in industries, educational institutions and the research community. This is evident by the large number of digital repositories of images, audio and video growing up all over the world. We have all heard the phrase “A picture is worth a thousand words”. Going along those lines, a video should be worth a million. Added to that is sound and interactivity. In order to use multimedia to its fullest extents, a thorough knowledge of its internals is essential, especially for people who are willing to take up multimedia as a career

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option. The first objective of this book is to meet this requirement, i.e. to explain as clearly as possible the fundamental concepts behind how different components of multimedia function. The technical level of the book is set at the graduate/postgraduate level. It is expected that after going through the book, the reader would comprehend the issues and standards related to the digitization, processing, compression and playback of various media components, as well as be competent enough to design multimedia presentations for a variety of applications. Due to the widespread use of multimedia applications world-wide, multimedia as a subject has been introduced in various forms in the curricula of schools and colleges all over the world. However, it being a relatively new subject, the number of related books in the market is still limited. The situation is aggravated by the fact that multimedia deals with a large number of different concepts put together. In fact, multimedia is often seen as meeting point of three different work areas: computers, communication and entertainment. Such being the case, a majority of the earlier books on multimedia dealt of multimedia presentations like CBTs. Other than these the books is also expected to be useful for researchers in fields, like distributed multimedia applications, real-time multimedia communications, Content Based Storage and Retrieval (CBSR), multimedia databases, multimedia document design and use of multimedia in education.

ORGANIZATION OF THE BOOK Chapter 1 provides an overview of what multimedia means and implies, major characteristics of multimedia presentations, what media types are involved, major uses and application areas of multimedia. Chapter 2 discusses the characteristics and differences between analog and digital forms of data representation, basic steps for A to D and D to A conversion, the parameters involved, related standards like Nyquist theorem, Fourier analysis of digital data. Chapter 3 provides an overview of visual display systems like monitors, adapter cards, cables and how they function, discusses the importance of monitor specifications, capabilities of different standards like VGA and AGP, difference between the CRT and LCD monitors. Chapter 4 discusses issues related to Text as the first multimedia element, difference between unformatted-, formatted- and hyper- text, provides an overview of the Unicode standard for text representation, factors defining the appearance of text like font and style, how text is inserted in a document, an overview on OCR, overview on text compression and file formats used. Chapter 5 describes concepts related to Image as the second multimedia element, different types of images, how color information is represented, various color models used and their applications areas, how images can be digitized using the scanner and the digital camera (image input devices), the interface standards involved, specifications of digital images, the difference between bitmap and vector forms of images, what is color management and why is it required, concepts of gamma correction, salient features of an image processing software in general (including important concepts like anti-aliasing, dithering, filtering, etc.), the image file formats used, characteristic of monitors and printers (image output devices) that affect image appearance and quality.

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Chapter 6 discusses issues related to Graphics as the third multimedia element, advantages of vector graphics over bitmaps, components of a graphics system, coordinate systems, overview of major graphics algorithms for line drawing, circle drawing, filling, clipping, etc., transformation techniques and parameters, overview of 3D graphics including 3D primitives, 3D coordinate systems, modeling and transformations, overview of surface characteristics and parameters involved, texture mapping techniques, types of lights in a 3D scene and their parameters. Chapter 7 deals with Audio as the fourth multimedia element, nature of sound waves and their fundamental characteristics, difference between musical sound and noise, the concept of decibels for measuring loudness of sounds, the phenomenon of masking and its importance, elements of an audio system namely the microphone, amplifier and loudspeaker, parameters of digital audio, synthesizers and the MIDI protocol, major components and I/O ports of a sound card, audio transmission standards and connectors, various types of audio recording devices, audio file formats, software audio players, an overview of the Dolby Digital System and the Digital Theatre System, digital audio broadcasting practices, use of audio in multimedia systems, main features of audio processing software in general. Chapter 8 discuss issues related to Video as the fifth multimedia element, principles of analog video camera, how color is captured by a camera and represented as RGB signals, problems in transmitting RGB signals, conversion of RGB signals into YC format, chroma sub-sampling, video signal formats, television broadcasting standards, techniques of digitizing video and playing it back on a PC, the video capture card and software, video recording formats and systems, video file formats, concepts related to video editing, main features of video editing software. Chapter 9 describes Animation as the sixth multimedia element, concepts of keyframes and tweening, difference between cell animation and path animation, what role the computer plays in creating animation, general guiding principles of animation, some popular techniques of creating animation, animation on the Web, overview of 3D animation, camera in 3D scenes, special effects, editing and transformation of animating objects, popular rendering algorithms, main features of animation software, animation file formats. Chapter 10 discusses the various compression techniques used, concept of CODEC, types of redundancies and compressions, lossless compression techniques (includes RLE, Huffman coding, arithmetic coding, LZ, LZW, DPCM, delta modulation, ADPCM), lossy compression techniques (includes transform coding, psycho-analysis, inter-frame correlation), image compression standards (GIF, JPEG), audio compression standards (MPEG-1 audio, MPEG-2 audio), MPEG-4, MPEG-7, MPEG-21. Chapter 11 discusses principles and related standards in optical storage on CD and DVD, how data is stored on a CD, the X rated speed of a CD, the various CD formats (CD-Digital Audio, CD-ROM, CD-Interactive, CD-ROM/extended architecture, Photo-CD, VCD, CD-Recordable, CD-Rewritable, CD+Graphics), magneto-optical discs (MO), interfacing with a PC, Laserdisc, error handling and correction, DVD specifications, CD vs. DVD, DVD formats (DVD-video, DVD-RAM, DVD-R, DVD+R, DVD-RW, DVD+RW). Chapter 12 discusses the essential concepts about networks and Internet, basic terminology, network types and topologies, network components (network card, cables, protocols), overview of TCP/IP

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protocol (IP addressing schemes, layered models, functions of each layer, subnet mask), details of associated protocols (TCP, IP, ARP, ICMP, UDP), IP routing and routers, DHCP, host name resolution and DNS, access methods, overview of the Internet, services offered on the Internet (e-mail, chat, network news, FTP, telnet), World Wide Web, Web browsers, search engines, connecting to the Internet, ISP, dial-up and leased lines, MODEMS, ISDN, overview of a Intranet, groupware applications, proxy server, Firewall. Chapter 13 discusses overview of various software and hardware architecture for supporting multimedia, graphical user interfaces, Windows multimedia support (API, DirectX, OpenGL, COM, .NET), hardware support (USB, SCSI, MMX, FireWire, SGI systems), distributed multimedia applications (videoconference, video on demand, interactive television, voice over IP), real time protocols (RTP, RTSP, RSVP), playback architectures (Windows media framework, QuickTime architecture, Ogg framework), streaming technologies, temporal relationships and synchronization between parallel media streams, overview of multimedia database systems. Chapter 14 gives the overview of multimedia document standards. It also discusses the need for a multimedia interchange format, SGML, ODA, MHEG, HyTime, OMF, and the issues related to digital copyrights and digital rights management. Chapter 15 discusses the steps for design and development of a multimedia presentation, generalized software life cycle model, conceptualization, story, flowline, script, storyboard, implementation, editing and authoring, authoring metaphors, testing and feedback, final delivery, report writing and documentation, an overview of computer games (includes concepts of genres, design, development, game engine, consoles, controllers, programming). Chapter 16 discusses an overview of virtual reality, forms of VR, VR applications, software requirements, hardware peripheral devices, VRML.

WEB SUPPLEMENT Instructor section ∑ PowerPoint Slides—Chapter-wise PowerPoint slides are provided as a tool for teaching aid. ∑ Sample Course Curriculum—A sample course curriculum based on the book is provided as a guideline to instructors. Student section ∑ Self-assessment Question Bank—A set of questions from actual examinations are provided for the student as a self assessment tool (provided in a separate file).

FEEDBACK In general all readers are encouraged to provide feedback about the content matter of book as well as any omissions for typing errors. The readers can also post technical queries regarding matters in the book at the OLC to which the author will attempt to provide appropriate answers, hints and guidelines.

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At the conclusion it must be emphasized that unlike the basic sciences, multimedia is a practical oriented subject. WE are learning a set of principles and procedures for the purpose that we might utilize them in creating better and improved applications. Hence practical utilization of the knowledge learned is at the heart of multimedia. In other words, theoretical aspects alone do not provide a complete understanding of the subject, learners must also know hot to build presentations using necessary software tools. I hope to address this requirement in a second volume which would deal exclusively with details of media editing, animation and authoring software required for creating multimedia presentations. Ranjan Parekh