Functional Requirements

Analyse hardware and software tools to meet functional requirements

Analyse hardware and software tools to meet functional requirements

Inside this reading:

2Functional requirements

Platforms3

Hardware and software platforms3

Platform selection4

Server operating systems9

Software applications12

Hardware components14

Connections14

Storage15

Security16

Video17

Sound19

CD and DVD21

Scanners OCR and digital cameras23

Summary24

Functional requirements

Functional requirements describe the characteristics of a planned system. The system could be a task, function or action. Determining the functional requirements happens in the early stages of a project, and is recorded in a functional requirements document that describes:

· Current system, its methods and procedures, the equipment in use, inputs and outputs and systems deficiencies.

· Proposed methods and procedures, the existing functions used and there improvements, functions of new capabilities and the impact this has on the business environment.

· Detailed characteristics of the functions to be performed and the performance requirements of the proposed system including response time, capacity limits and accuracy.

· Environment, that is, a description of the

–software environment including the operating system, programming language and database management system

–hardware environment including processors, storage, input and output devices, communications environment both hardware and software and the interfaces with other corporate applications.

The functional requirements should be very specific about the type of hardware and software platform needed for the proposed system. This information is used as the basis for determining the selection criteria for computer resources. The example below is an extract from the functional requirements for the upgrade of a DVD authoring tool used for editing DVD videos:

…..the minimum requirements for each workstation are:

Dual x86 compatible processors with a Sysmark 2002 score of 160 or greater....

The writer of this functional requirement is being very specific and clear. Unfortunately, this is not always the case and sometimes you will need to analyse the functional specifications closely to determine what is actually needed. The above example states that each workstation must have a dual x86 processor with a Sysmark 2002 performance score of 160 or greater. Sysmark is a computer benchmarking tool that enables performance comparisons across multiple platforms. It is used to benchmark workstations, laptops and desktop PCs. Standard Performance Evaluation Corporation is a non-profit organisation that maintains a set of benchmarks used to evaluate the performance of new computers including servers and corporate machines.

Platforms

A computer platform refers to the components that make up a computer system. Computer components can be grouped into hardware and software. There is a wide variety of computer platforms in the marketplace; some platforms may be familiar, like Wintel, while others may be unfamiliar, like QNX. Others may not be thought of as computer platforms at all but are, for example, your mobile phone or games console.

Hardware and software platforms

Hardware platform refers to the hardware components that make up the computer system while software platform refers to the operating system or programming language developed for the hardware. There are defined terms used in the IT industry to describe the types of platforms including:

· Wintel

· Lintel

· Mac, Macintel

· Mainframe

· UNIX

· Alpha AXP

· Java

· .Net

The Wintel platform refers to a Microsoft Windows operating system (the Win in Wintel) that uses an Intel x86 or compatible processor. The Intel x86 or compatible reference refers to a small number of processor manufactures that produce a computer processor that is compatible with the x86 instruction set. Some examples of x86 compatible processor manufacturers are AMD, VIA and Transmeta.

A Lintel platform refers to a Linux operating system that uses an Intel x86 or compatible processor.

A Mac platform (Apple Macintosh) refers to a computer system using Apple hardware and a Mac OS operating system. The current processor used in Apple hardware is produced by IBM and is the 64-bit PowerPC G5. However, in 2006 Apple moved to the x86 Intel hardware architecture (Macintel). Mac OS X ‘tiger’ is the current Mac operating system.

A mainframe platform refers to a large processing intensive computer system. The hardware and software architecture can vary depending on the manufacturer. An example of a mainframe computer is the IBM zSeries. The zSeries is a high-end IBM product that uses 64-bit architecture. The zSeries uses IBM multichip module processor and can be configured to use a maximum of 1728 processors. IBM uses virtualisation technology to run multiple operating systems on a single mainframe. This allows the flexibility to install operating systems that best support the provided service. Currently IBM holds more than 90 percent of an expanding mainframe market.

A UNIX platform refers to a computer system that uses the UNIX operating system, or derivative, on a variety of hardware platforms. UNIX is able to run a variety of processors including x86, RISC and PowerPC. Over the years UNIX has evolved into many different proprietary and Open Source operating systems. Sun Solaris is an operating system based upon the UNIX SunOS Open Source operating system.

In modern computing we are no longer limited by the physical platform of computer systems. With the use of virtualisation technology we can have multiple platforms on the one physical machine. With the use of software like Virtual PC or VMware the boundaries of running one operating system per physical machine are removed. This makes the consolidation of multiple platforms onto one physical platform possible, reducing the overall cost and the flexibility to add capacity as needed.

Platform selection

Platform choice is an important consideration very early on in a project. Most projects cannot be changed midstream, as there are many different factors such as file formats and protocols that cannot be changed. These often differ from platform to platform. It must be noted that development can be completed on virtually any platform; however some are easier and more cost effective than others.

In the end, developers have to assess what system is best for their project. As a developer, you will need to consider some technical elements such as:

· what technology is supported by the platform

· compatibility with existing systems

· what systems or platforms you are developing for

· the type of media that will be used

· the formats of any legacy (old) content

· what funding is available to purchase software and hardware.

Server platforms

There are many different types of server platforms that perform many different functions. A server’s platform mainly depends on the type of service that it is providing. Some of the functions provided by a server are:

· mail services

· web services

· transactional processing services

· streaming media services

· remote access services

· file storage and retrieval services

· network access

· application services.

To select an appropriate server platform there are numerous issues to consider, including:

· Budget—How much money has been allocated for the purchase of the equipment? Servers can range in price from as low as $1,000 dollars for a low end x86 compatible system to $200,000+ for an IBM zSeries Mainframe.

· Total cost of ownership (TCO)—This refers to the original cost and the ongoing maintenance cost for the life of the equipment and must be factored in when selecting a server platform.

· Personnel skills and experience—Developers and IT Administrators need to be confident working with the chosen platform. Is the IT team able to support or develop software for the platform?

· Functional requirements—What is the function of the server, what are the time requirements (response and processing times), how many transactions per second are required, what are the storage requirements, what is the number of concurrent users, what type of content is being stored? How does it integrate with the current system? What operating system does the application require?

· Project or business requirements—Does the platform conform to present and future business requirements? What is the technical direction of the organisation? Are there any plans to migrate from one platform to another?

· Security—What are the security requirements and how sensitive is the data being stored? Who needs to have access?

When selecting a server platform you must consider all these points and any other factors that you can identify for your particular project.

Server diagrams

When designing a server system, it is important to understand how all the different parts of the IT system function and fit together. The clearest way to do this is to use a diagram. Your diagram should describe the macro and micro server environment, which is the overall design of how the servers interact with each other and the IT environment, and the individual design of each server’s sub-system. When drawing your diagrams you will need to record information about:

· the server platform, processors, RAM, HDD, operating system, etc

· the role of the server, the software installed, etc

· data flow (both internally and externally)

· security hardware and software devices (eg firewalls) needed

· the network name and IP addresses.

Figure 1: Logical server diagram

Figure 1 is an example of a logical server diagram showing the logical connections, the server roles and the platforms types. It is used as an overall view of the network.

Figure 2: Physical diagram

Figure 2 is a physical diagram of the servers mentioned in Figure 1. It shows the physical installation of the equipment onto a rack. It is used in the planning stage of hardware installation.

Figure 3: Detailed server hardware configuration

Figure 3 is a diagram showing the detailed hardware configuration of a ProLiant server. This diagram is used to record the sub-systems of the server.

Server operating systems

One of the major decision points of choosing a platform is the selection of the operating system. Choosing the operating system is an important part of meeting the overall functional requirements of the system. When considering the operating system you will need to take into account the following.

· Hardware platform—Not all operating systems will function with every hardware platform. Windows will only work natively on an x86 platform. When an operating system works natively it means that the machine code being executed is embedded within the processor; there is no emulator that sits between the operating system and the hardware. An emulator is a piece of software (executed natively) that tricks the operating system into thinking it has been installed on the correct hardware platform. Virtual PC for Mac is an emulator installed on Macintosh hardware to use a Windows operating system.

· Current IT infrastructure—What type of hardware, software and programming environment is in use? Will the new operating system be compatible with current applications?

· Future IT infrastructure—What is the organisation’s short-term and long-term IT strategy? How will the operating system fit in with future needs?

· Support—Who will be supporting the operating system; will it be supported in house, by the vendor or by a third party?

There are many server operating systems available in the IT marketplace. Each operating system is pitched at a different market level. Some operating systems are used by small to medium enterprises while others are used by large enterprises or government institutions. It is important to align the purchase of the operating system with IT direction and business goals. Some examples of operating systems vendors follow.

Novell

Novell’s Open Enterprise Server is a server operating system that uses the Linux and Netware kernel. Open Enterprise Sever provides ease of network management using NetWare management services with greater application compatibility through Linux. Go to the Novell website at www.novell.com to find out more about the different products available for server operating systems from Novell.

Apple

Apple Mac OS X server ‘Tiger’ is a server operating system built on a UNIX foundation with a Mac microkernel that takes advantage of the open source BSD software. Mac OS X server provides a stable, high-performance, 64-bit computing platform for enterprise applications, web and email services, directory services, and file and print services. It has chat and weblog services built-in and provides service to Windows workgroups. Go to the Apple website at www.apple.com/server to find out more about Mac OS X server.

Microsoft

Microsoft Windows 2003 server is an operating system that provides many different network services. Security, one of the major criticisms of Windows 2000 server, has been addressed by turning off all non-essential services on startup in Windows 2003. There are many different versions of Windows 2003 server including Small Business server, Enterprise Edition, Web Edition and Data Centre Edition covering a wide range of user needs.

SCO group

The SCO group main product is OpenServer. OpenServer is a UNIX operating system that is very stable, reliable and secure. SCO OpenServer uses Open Source software like Apache to provide greater application support. For more information on SCO OpenServer and other SCO operating systems go to www.sco.com

Sun Microsystems

Sun Microsystems proprietary operating system is Solaris. Solaris is a certified UNIX version that is available for free. Solaris has all the benefits of UNIX with an easy graphical user interface. To learn more about Solaris go to www.sun.com.

IBM

IBM has a range of server operating systems including VM, CMS, zVM, Linux, AIX, zOS. VM/CMS is an operating system used on IBM mainframes. VM/CMS is actually two operating systems VM (Virtual Machine) and CMS (Conversational Management System). For more information on IBM server operating systems go to www.ibm.com.

HP

HP has a number of server operating systems for multiple platforms. Some HP operating systems are OpenVMS, Tru64, HP-UX. For more information on HP operating systems go to www.hp.com.

There are many more server operating systems than those listed above. For a exhaustive list of available operating systems go to en.wikipedia.org/wiki/List_of_operating_systems.

Software applications

Software applications come in many different forms and functions. Software applications are installed on servers, workstations and personal computers, and can be developed inhouse or off-the-shelf packages. Inhouse development is when an organisation develops a software application for a particular purpose for use by that organisation only. An example is an insurance company that uses a proprietary software application to handle insurance claims.

A commercial off-the-shelf package is ready-made and available to anyone willing to purchase it. There are many different categories of off-the-shelf applications. Some of the more common applications are word processor, relational database management systems, graphics programs, email servers and clients, web browsers, enterprise resource planning and many more. When selecting a software application make sure the application:

· meets user requirements

· addresses business needs

· is technically feasible

· aligns to future IT and business goals.

There are many platforms available to the developer when developing inhouse software applications. Two common development platforms are the Java 2 Platform from Sun Microsystems and Microsoft’s .Net platform. For more information about the Java 2 platform go to java.sun.com/j2se/ and for the .Net platform go to www.microsoft.com/net/.

Technical specifications for the developer’s computers is also important. Every year they change, but the general rule is that a developer needs a late model computer to develop and test applications.

To illustrate an example of a high-end multimedia development workstation for late 2005 see below:

Dual AMD Opteron® 280/2.4GHz (dual-core) 1GHz HT

· Dual NVIDIA Quadro FX4500 512MB PCIe

NVIDIA Quadro G-Sync Card

6GB (4x1GB + 4x512MB) DDR-400 ECC reg for Dual Processor

· Dual 146GB U320 SCSI 15K

16X DVD+/-RW, DL, LightScribe

· U320 SCSI Controller w/RAID

· No floppy disk drive kit

· Broadcom 5782 10/100/1000 PCI

· Sound Blaster Audigy 2 ZS PCI

· 6 x USB 2.0 ports, 1 x PS/2, 1 x Serial, 1 x Parallel Ports

· USB 2004 Standard Keyboard

· HP USB Optical Scroll Mouse,

· Microsoft Windows XP Professional

Dual HP L2035 20-inch TFT Flat Panel Display

This type of computer would be appropriate for processor intensive multimedia development.

Hardware components

Connections

The computer equipment required for a professional software development team has to be reliable and also very fast. The right connection choice can save a development team many hours per day. Here is an overview of some of the hardware connections available.

Fibre channel

Fibre channel is a high speed data transfer technology used in connecting a server to storage area networks. For more information on fibre channel go to www.seagate.com/support/kb/disc/fibre_channel.html and read the article ‘Fibre channel’.

SCSI

Small Computer Systems Interface

SCSI was originally built into Macs but is now commonly used in many other platforms. Generally speaking it was considered a faster connection technology when compared to older formats like parallel ports. Basic SCSI allows multiple internal and external peripheral devices to connect with the system. To view SCSI connections and speeds go to www.ramelectronics.net/html/scsi_connecters.html and review the article on ‘SCSI Connectors and SCSI Cables’.

IDE

Integrated Drive Electronics

This is a connection format that has been used for many years for connecting internal devices (hard drives, floppy drives, etc). Its true name is ATA. To find out how IDE works, go to the How Stuff Works website and read the article ‘How IDE Controllers Work’ at: www.howstuffworks.com/ide.htm

USB

Universal Serial Bus

A consortium of major industry players (including Microsoft, IBM, Compaq) in 1995 agreed on a standard for connecting devices. This connection would be ‘plug and play’ and would function without drivers. It is now the most common connection format for peripherals. To learn more about USB go to www.usb.org and read the many articles about USB.

Firewire

(IEEE 1394)

Originally introduced by Apple in the late 1980s, this is a fast data standard for mass storage. Now it is also supported by Windows XP. It can connect multiple computers and peripherals but is deemed an invaluable asset to developers particularly for video transfers. For more information about firewire go to www.apple.com and search for ‘Firewire’.

The following table reveals some basic details about connection types and speeds:

Connection

Approx Transfer rate

Serial port

115 Kbps

Standard parallel port

115 Kbps

IDE

2.5 Mbps

SCSI-2

10 Mbps

Ultra 3 SCSI

80 Mbps

Fibre channel

100–4000 Mbps

High speed USB

480 Mbps

IEEE-1394 Firewire

100–1600 Mbps

Storage

Direct attached storage

Direct attached storage is storage that connects directly to the server or workstation. The storage medium could be an internal hard disk, an external hard disk, compact flash, or a range of many other external or internal devices.

Storage area networks

Storage area networks (SAN) are sub networks that provide high speed access to data. A SAN typically pools data storage devices into one area. Each storage device is connected to each other and to the network servers through high speed switches. SANs allow multiple servers to use the same data stored in the SAN. SANs offer unlimited storage space, easy backup and restore and many other advantages. To learn more about SANs go to www.dothill.com/tutorial/tutorial.swf and complete the tutorial on SANs.

Network attached storage

Network attached storage (NAS) is a hard disk device with the only function being to provide file services. NAS offers a quick way to increase network storage capabilities. A NAS device typically does not provide any other services like email, authentication and so on. For more information about NAS go to compnetworking.about.com/od/itinformationtechnology/l/aa070101a.htm and read the article ‘Introduction to NAS—Network Attached Storage’.

Security

Backup strategies are essential to ensure that development is completed in a professional manner. Generally, if backup and storage is considered as a secondary process, then production will suffer major setbacks. The importance of this strategy cannot be emphasised enough!

Remember local backups should be stored in fireproof safes and off-site backups should be completed at least on a weekly basis. (Again, this all depends on the size and complexity of the project).

Developers have always created backups on large networks drives/servers and this process still continues. However, external solutions have always played a large role too. Previously, developers used to store their files on network drives, CD-ROMs and sometimes even external devices such as Zip, Jaz or Syquest drives.

Today, cheaper larger solutions are plentiful with the market being saturated with 40GB USB external hard drives for less than $200, DVD burners and USB flash drives (memory sticks) as cheap as $20 for 128mb.

The reason external solutions have played a role is due to the following reasons:

· working from multiple sites (eg home)

· creating multiple backups

· backing up while the corporate network is down

· reducing bandwidth utilisation

· to allow self regulation

· external storage is affordable

· media burning software such as Easy CD Creator or Nero is extremely easy to use.

Storage estimates

The Network Manager should be advised by the Project Manager of project file storage and of any special backup requirements. An estimate of the total disc storage space required can be made from the product specification document. A reasonable estimate is to allow for five times the projected byte size of the final product specification document. This allows for a working space equivalent to the final product size, a similar volume for finished assets and another similar volume for the creation of a final product image.

Video

Video cards and resolution

Video cards and the software associated with them control the resolution of the text, pictures and video that appears on the screen (ie the screen resolution). Software often requires a video card that can display colour photographs and colour video. It is therefore important that your video card can display a large number of different colours.

It is important that you know how to vary the resolution of what is displayed on your computer screen, that is, the number of dots (technically known as pixels) that make up the picture on your screen and, therefore, its definition or clarity. Most video cards are accompanied by software that enables you to control the resolution of the display screen according to the software that you are using. Common settings are:

· 640 x 480

· 800 x 600

· 1024 x 768

· 1280 x 1024

The lower the numbers results in a lower resolution. A 640 x 480 setting offers a 'chunky' appearance, but many older software packages will run only in this mode. 800 x 600 is a fairly safe general setting for most software, with more developments moving to 1024 x768. Getting this setting wrong is a common reason for software not working properly.

Video editing software

For efficient digitisation of video resources, the installation and setup of a video capture card is essential. This enables the efficient capture of video from a variety of sources and will speed up video capture from others. Video capture cards can be connected to sources such as a VCR or camcorder via a firewire (which offers much quicker transfer than the standard USB connection).

Conversion of videos from satellite and terrestrial TV, camcorder or VHS tape, to a suitable digital format is easily accomplished with a video capture card. Many modern computers have these facilities already installed, but they are not standard.

See the following websites for more information:

· Adobe Premiere software at: www.adobe.com

· Pinnacle Systems offer a wide range of products, e.g. Studio 9: www.pinnaclesys.com

· Final Cut Pro (Mac) software at: www.apple.com/finalcutpro

· Matrox offer a wide range of products: www.matrox.com

Movie Maker is also bundled with Windows XP.

When using the above packages, it is important that you are aware of the different formats in which video can be stored on a computer. Most video editing packages allow you to save images in different formats and to convert from one format to another. The most common formats are as follows.

AVI: Audio Video Interleave format

Older format but still popular, but giving way to MPEG, which takes up less storage space and maintains better quality.

MPG (or MPEG): Motion Picture Expert Group

Probably the most common format for storing video.

WMV: Windows Media File

Also in common use. Quite economical on space.

ASF: Advanced Streaming Format

This is a file format that stores both audio and video information and is specially designed to run over the Internet. ASF enables content to be delivered as a continuous flow of data with little wait time before playback begins. This means that you no longer have to wait for your audio and video files to fully download before starting to view them.

QuickTime

The standard format for storing video files on Apple Macintosh computers, but also available for the PC. Economical in terms of storage space. See www.apple.com/quicktime.

Sound

Soundcards

Soundcards are essential hardware for multimedia use and development. Most multimedia computers are fitted with soundcards as standard.

There are soundcard controls within all operating systems that enable you to adjust the output volume of your soundcard and the input sensitivity of the microphone. This is vital as recording quality is a ‘must’ to get right before commencing your sound recordings. Ensure that you complete a thorough testing phase of this.

SoundBlaster is one of the most popular brands: www.soundblaster.com

Loudspeakers/headphones

Speakers or headphones are essential for listening to sound recordings. When purchasing speakers it is worthwhile checking that they have their own inbuilt amplification system. The sound level of all speakers or headphones can be controlled under the operating system, but good speakers have a volume control knob that also enables the user to adjust the volume manually. Headphones can be integrated with a microphone (the so-called ‘pilot's headset’ that is used in language laboratories). Stereo speakers or headphones are advisable for most applications.

Microphones

The importance of selecting the right kind of microphone is often not appreciated by novices. For good quality sound recordings the developer needs a 600 Ohm low impedance microphone with a 3.5 mm jack plug.

A dynamic microphone is satisfactory but provides a softer signal than a condenser microphone (also known as a powered microphone).

Dynamic microphones will work with most soundcards, but condenser microphones work only with soundcards that can provide power to the microphone. Using the wrong kind of microphone is a common reason for failing to get multimedia software to work properly.

It is advisable to purchase a microphone that has its own on/off switch.

The level of the input signal to the microphone can be controlled under the operating system. A common mistake made by newcomers to multimedia applications is a failure to set the input signal control properly so that very faint sound, or no sound at all, is emitted when playing back recordings made by the user.

Sound recording and editing software

Below are some examples of sound recording and editing software.

· Adobe Audition: The ‘industry standard’ and the successor to Cool Edit Pro: www.adobe.com

· Audacity (freeware): Allows for all the basic features of editing, and copes with different formats, and will even import MIDI: http://audacity.sourceforge.net

· AudioSurgeon, one of a range of useful products produced by Voyetra, a modestly priced audio editing package: www.voyetra.com/site/products/audiosurgeon/

· Sound Recorder: Supplied with Windows. Rather primitive, with only basic operations.

When using the above packages, it is important that you are aware of the different formats in which sound can be stored on a computer. Most sound editing packages allow you to save images in different formats and to convert from one format to another. Some of the common formats include:

WAV

Until recently, WAV has been the most common format for sound files. WAV reproduces high quality sound but takes up quite a lot of space.

MP3

MP3 is the standard format for storing sound files on the World Wide Web. The advantage of this format is that it compresses the sound, therefore saving space without a significant loss in quality. See www.mpeg.org

Online tutorials

At the Webmonkey site look under ‘Topics’ to go to tutorials on Multimedia (including audio) at: http://webmonkey.wired.com

CD and DVD

CD-ROM stands for Compact Disc Read Only Memory. A CD-ROM is an optical disk onto which data has been written via a laser. As you would realise, floppy disks are not used regularly any more.

CD-ROMs can store at least 650 megabytes of data. A standard high-density floppy disk (1.44Mb) can store a 500-page novel. A single CD-ROM, however, can comfortably accommodate 500 medium-length novels. When graphics and audio and video recordings are stored in computer-readable format they take up much more space than text, and they can only be made available to consumers in reasonable quantities if they are stored on CD-ROM or DVD.

Multimedia CD-ROMs are designed mainly for use on stand-alone computers. This is because the main target of CD-ROM manufacturers is the home user. This is not to say that CD-ROMs have no place in businesses, schools and other educational institutions; the main problems are technical and organisational. It was not until around 1993-94 that multimedia CD-ROMs began to appear in large numbers. Now CDs are increasingly being replaced by DVDs.

DVD drives

DVDs (Digital Versatile Discs) look just the same as CD-ROMs and audio CDs, but they are much more versatile. They are already in widespread use to store movies that can be played back on domestic TV sets. DVDs can also be used to store computer data, which can be read by a computer equipped with a DVD-ROM drive.

A DVD player is the name given to the device used in home entertainment systems to play back video and audio. A DVD player can play:

· DVD-Video discs (also referred to as DVD-Movie discs) eg containing full-length feature films, videos of concert performances, etc.

· Audio CDs.

A DVD-ROM drive, as fitted in a multimedia computer, can play:

· DVD-ROM discs, which consist of combinations of computer programs and high-quality motion video.

· CD-ROMs.

Some DVD players cannot normally be used to play DVD-ROM discs (but note this technology is in the process of moving towards fully integrated systems).

Modern DVD-ROM drives can also write to CD-ROM, using CD-R (recordable) and CD-RW (rewriteable) discs. DVD-R (recordable) and DVD-RW (rewriteable) drives are now more widely available.

The main advantage of all types of DVDs is that they offer very high quality video and sound.

DVD-Video discs

Standards for DVD-Video are still in the process of settling down. An annoying aspect of DVD-Video is that the world is carved up into six regions, also called locales, each of which has its own DVD standard. DVD-Video discs are regionally coded (look for a small standardised globe icon on the packaging with the region number superimposed on it). If a disc plays in more than one region it will have more than one number on the globe.

DVD-Video discs have impressive advantages. You can play back a full movie with 8-channel surround-sound cinema effects. You can easily jump to a particular sequence (a scene or chapter), and DVD-Video discs often offer alternative soundtracks in different languages, subtitles, closed captions (subtitles in the same language as the one in which the film was recorded) and information about the director and cast, as well as the possibility of previewing and playing your favourite scenes over and over again.

DVD-ROM discs

DVD-ROM discs are not subject to the same geographical restrictions as DVD-Video discs. They only run on computers equipped with a DVD-ROM drive and cannot be played on a domestic DVD player but, having said that, DVD technology is in the process of moving towards fully integrated systems. DVD-ROM discs combine computer programs and movies and are becoming increasingly flexible as an instructional medium.

If you want to complete an online tutorial on CD and DVDs, then try one of these sites:

· www.roxio.com/en/support/ecddvdvc/index.jhtml (Click on the Tutorials link.)

· www.htmlfixit.com (Click on web related tutorials.)

· www.cs.cf.ac.uk/Dave/ISE_Multimedia This site also has some useful information. Look for ‘HTML Course Notes’ then click on ‘Storage media’.

Scanners OCR and digital cameras

Scanners

A scanner is a device that copies hard copy information (printed page, graphic image, photograph, etc) into digital data, translating the information into a form a computer can store as a file. Thus, it is possible to make a digitised copy of a printed page, graphic image or photograph. Simple graphic images are usually stored in a format known as GIF. Photographs are usually stored in a file format known as JPEG or JPG and they can then be printed on a colour printer, sent as an email attachment or incorporated into a website.

Scanners do not distinguish text from graphic images and photographs, so you cannot use a word processor to directly edit a page that has been scanned. To edit text read by an optical scanner, you need optical character recognition (OCR) software to translate the image into ‘real text’, that is, a format that can be read by a word processor.

The most popular type of scanner is a flatbed scanner. This looks a bit like a photocopier and works in a similar way. You lay the picture or page containing the text to be scanned on a glass plate, start the scanning software and watch the digitised image appear on screen. The image can then be saved as a file on your hard disk. Text saved as an image can then be converted into ‘real text’ with OCR software. This does not work 100%, as broken characters and faded characters are liable to be misread, but surprisingly good results can be achieved.

Some scanners are small handheld devices that you slide across the paper containing the text or image to be copied. Handheld scanners are fine for small pictures and photos, but they are difficult to use if you need to scan an entire page of text or larger images.

If you want to complete an online tutorial on scanner use, then try the this website: www.corkrum.com/tutorials/scanners.html

Digital cameras

Digital cameras are a major piece of equipment for the multimedia developer. To learn more, try an online tutorial on digital cameras such as one at Photoxels: www.photoxels.com. Go to ‘Tutorials’.

Summary

The selection of the best hardware and software tools for your specific solution is often complicated. It can feel like an overwhelming task to keep abreast of all the hardware and software tools and components that, in general, are significantly upgraded every two or so years. There are also difficulties with ensuring that your selections will be fully compatible with all other hardware and software that is currently in use or that will be used in the near future. Therefore, ongoing research to keep your knowledge of hardware and software up-to-date is vital in ensuring successful projects.

2004

1678_reading.doc

© State of New South Wales, Department of Education and Training 2006