1Multimedia Components (Develop & Delivery System) IntroductionMultimedia Computer develop systemMultimedia Application DevelopMultimedia Personal ComputerSystem requirement for MM DevelopMultimedia Delivery system
2Introduction Hardware environment for developing multimedia Multimedia programs with digital sound, stills, animation, and motion video increase the required performance needs of a personal computer to a completely new levelTechnology has moved forward with faster, more efficient microprocessors suchas the Power Mac and Pentium
3MM Computer Development system Typical Hardware Components of MPC
4Features of MM Computer Development system Windows-based and Macintosh computers are used to create multimedia titles. Because the Macintosh was the first popular personal computer to provide a graphical interface - has superior handling of graphics and cross-platform capabilities, it has been used extensively in multimedia development.Today, a Pentium III 500 processor is considered the minimum needed for development work. A Pentium tit 750 or better is desirableMultimedia titles are extremely memory-intensive. 128 MB of RAM min Req., with 256 MB being more desirable.For video -digitized using a video capture card. The card fits internally within the computer, and a video source (camera, VCR, TV) is then plugged into the card.
6Multimedia Components (Computer Architecture) Hardware ElementsInputoutputMemorySpecialized MM HardwareStorage devicesOperating SystemDigital Audio and Video Capturing
7hardware components of the basic computer model communicate with microprocessor software components of the compter communicate with the operating system
8Input various data formats Store and retrieve digital multimedia data Multimedia applications offer significant challenges to computer architecture in terms of its ability to:Input various data formatsStore and retrieve digital multimedia dataManipulate and edit multimedia data; for example, editing graphics, audio, and digital video filesOutput multimedia data including converting digital version into an analog format suitable for the end user
11Inputs:Keyboards- also special layouts for limiting and controlling user inputMouse-also track balls, joysticks, and similar devicesGraphic tablets-used in drawing and painting applicationsScanner-capable of capturing images ranging from black and white to millions of colorsDigital camera-capable of capturing and converting images and video directly into a computer-digital formatAnalog audio input from microphones and audio player sourcesAnalog video input- raw and processed video input. Some hardware systems even decode television signals for display.Network support for distribution of multimedia filesModem
12OutputsHigh resolution monitors capable of displaying black and white to millions of colors. A 256-color display is considered the minimum requirement for multimedia display.Specialized projection devices to replace or augment single user monitor/displays for larger audiences. These devices usually function in lieu of or simultaneously with a computer monitor.Audio output to speakers or to other audio devices such as amplifiers or tape devices.Raw video output for television monitor display-the computer typically creates a television video compatible signal
13Specialized Multimedia Hardware Multimedia hardware focuses on the ability to capture, store, and present text, pictures, audio, and video.Each type of data, the computer must be able to convert it into digital format and store that data in a file. This file can then be edited and/or applied into a multimedia presentation product.The presentation software, in conjunction with the operating system, then converts the data back into an analog format that can be viewed, heard, or experienced by an end user
14Fig 3.8 Cost Comparison of various forms of Storage As with other computer system components, secondary storage media and devices must be chosen to support information systems objectives, and ultimately the business objectives. There’s a trade off between access time, cost, capacity, and portability among different media and devices. Figure 3.8 shows some of these tradeoffs, comparing secondary storage to primary storage. For example, the most cost effective media to use for secondary storage magnetic tape. Tape also has a fairly large storage capacity and is relatively cheap. However data stored on a tape cannot be accessed quickly, nor can records stored on tape be accessed in random order. Likewise, although hard disks have a large storage capacity and are relatively inexpensive, for the most part they are not easily portable. Thus a tape would not be a good storage medium for someone who needed to look up customer records while handling customer phone calls, and a diskette may be more appropriate than a hard drive for someone who continually works on spreadsheet files on different computers.
16Access methods Sequential access: records must be retrieved in order Direct access: records can be retrieved in any orderDirect access storage devices (DASDs)Data and information can be retrieved from secondary storage in two main ways. Access can be either sequential or direct. In sequential storage, records stored on a secondary storage device must be retrieved in the same order in which they were stored. For example, if a university has student records stored on a computer tape in order of ascending social security numbers, using sequential access, records must be retrieved in ascending order of social security numbers. Thus, to edit the record of a student with social security number , roughly half the records stored in the student file must first be read before the desired student is found. Thus, sequential access is a very slow way to access a single records.With direct access, records can be retrieved without starting at the beginning of the the file and without reading many other records. Thus data can be retrieved in random order. This can happen on direct access storage devices (or “daz-dees”) since each location on the storage medium has a unique address and the read/write head can go directly to the required location.
17Devices and Media: Magnetic Media Magnetic tapesMagnetic disksRAIDStorage Area networks (SAN)The most commonly used forms of secondary storage include magnetic tapes, disks, and optical disks. Magnetic tape allows only sequential access of data, while others allow both direct and sequential.Magnetic tape is similar in composition to the kind of tape found in videotapes and audio tapes. A plastic film is coated with iron oxide which is magnetized to represent bits. Note that while data existed as electrical in a computer, it exists as magnetized areas on magnetic tapes and disks. A main use of magnetic tape is to backup disk drives.Magnetic disks are similar to magnetic tapes in that areas are magnetized to represent bits. However the disks’ read write head can go directly to the desired record, allowing fast data retrieval. Magnetic disks can range from small and portable, such as diskettes with 1.44MB of storage capacity, to large capacity fixed hard disks which are more expensive and less portable.RAID stands for redundant arrays of independent or inexpensive disks. RAID technology is fault tolerant; that is, it allows data to be stored so that no data or transactions are lost in the event of disk failure. RAID involves using multiple hard disks in a special controller unit and storing data across all the disks in conjunction with extra reconstruction information that allows data to be recovered if a hard disk fails. RAID 1, or disk mirroring, is the simplest form, storing the same data on two hard disks. RAID 5 is a more complex form that uses numerous disks and recovery information. RAID 5 is more efficient and cost effective than is disk mirroring.A storage area network connects servers and storage devices in a network to store large volumes of data. Data stored in a storage area network can be quickly retrieved and backed up. The use of storage area networks will likely increase in the near future.
18Devices and Media: Optical Media Optical disksCD-ROMCD-W (aka WORM)CD-RWMagneto-optical (MO) disksDigital video disks (DVDs)Unlike magnetic media, optical disks use low power lasers to mark the surface of a plastic disk in order to represent bits. Optical disks have a very high storage capacity, although generally the access time is slower than that of magnetic media.There are three kinds of optical disks. The oldest is CD- ROM, which stands for compact disk read-only memory. Data or programs are recorded on CD- ROMs by the manufacturer, and cannot be modified. CD-ROMs are used for the mass distribution of large quantities of data, such as software programs, encyclopedias, or documentation.CD-Writable, or CD-W, disks are also known as WORM disks. WORM stands for write once, read many. This means that you can record on the disk, but not change data once it has been recorded. An ideal use for these disks is to archive data.CD-RW which stands for read-write, works like the diskettes that you are used to, with greater storage capacity. These disks can hold 740MB of data, far greater than the 1.44MB held by most diskettes. Data can be recorded,modified, deleted or replaced.Magnetic optical disks combine magnetic disk and optical technology. A laser beam alters a magnetic surface which can be erased by demagnetzing it. Magnetic optical disks are read-writable and portable, but hold over 100 times more data than a diskette and can be accessed more quickly.DVDs are physically similar to CD-ROMs, but have a far greater storage capacity. A DVD can hold at least 4.7 billion bytes of data. Quality of DVDs surpasses that of CD ROMs, and DVD drives are faster than those of CD ROMs.
19Three Stages of Audio and video Capture, storage and Playback
20Video hardware consists of devices to display and capture video Video hardware consists of devices to display and capture video. Video display devices, often called graphics adapters, enable the computer to present information on monitors capable of displaying up to 16 million colors