Multimedia: One Mark Questions, Book Back Answers and Notes

About Multimedia

Medium ~90 min study

Multimedia means using more than one medium together to present information. A web page with a paragraph of text, a photo, a short video clip and background music is a simple example. The chapter starts from this definition and then takes each of the five elements in turn: text, images, sound, video and animation.

For every element you need to know two things: how it is stored on a computer and which file formats are used for it. Images, for instance, are either raster (made of pixels) or vector (made of shapes described mathematically), and that one difference decides how a picture behaves when you enlarge it. After the elements, the chapter moves to how a real multimedia product is made, step by step, and who does what in the team that makes it.

Book back questions from this chapter usually ask you to match a file extension to its media type, pick out the correct order of production steps, or name the team member responsible for a job. Learn the lists exactly as the textbook gives them. Many one-mark questions turn on a single word, such as whether a format is lossy or lossless.

What you'll learn

• Define multimedia and name its five elements.
• Tell raster images from vector images and explain what happens when each is enlarged.
• Match common file extensions to text, image, sound and video.
• List the twelve steps of multimedia production in the correct order.
• State the job of each member of a multimedia production team.
• Give examples of multimedia use in education, business, medicine and public services.

Before you start

• Basic use of a computer, including saving and opening files.
• Knowing that a file extension such as .jpg or .mp3 tells you the file type.
• Everyday familiarity with web browsers and the internet.

Multimedia explained

Multimedia: Elements, Formats, Production and Uses

The five elements

Text can be static text, such as headings and paragraphs that stay fixed, or hypertext, which is made of nodes connected by links so the reader can jump between topics in any order. Images are either raster images, stored as a grid of pixels, or vector images, stored as lines, curves and shapes described by mathematical formulas. Sound can be recorded digital audio or MIDI (Musical Instrument Digital Interface), which stores instructions for an instrument or synthesizer instead of the sound wave itself. Animation shows a series of still images quickly one after another so the eye sees movement. Video is a sequence of recorded frames shown at a steady rate, usually with sound.

File formats

Text is saved as plain text (TXT) or as Rich Text Format (RTF), which keeps formatting and can be opened by different word processors. Common image formats are TIFF, BMP, GIF, JPEG and PNG. JPEG uses lossy compression, so some detail is thrown away to make photographs smaller. PNG uses lossless compression and supports transparent backgrounds, which makes it popular for web graphics. WAV is an uncompressed audio format, while MP3 and OGG compress sound to save space. For video, AVI and MPEG are the formats to remember; MPEG has several standards used for everything from CDs to digital television.

The twelve steps of production

The textbook lists these steps in order: conceptual analysis and planning, project design, pre-production, budgeting, forming the multimedia production team, hardware and software selection, defining the content, preparing the structure, production, testing, documentation, and delivering the multimedia product. Planning fixes the goal and the audience. Budgeting estimates the cost. In production, the text, graphics, sound and video are created or collected and put together with authoring software. Testing checks that every link and media file works, and web-based products must be checked in more than one browser. Documentation records how to install and use the product, and delivery puts it on disc or on the internet.

The production team

A large project needs several specialists. The production manager plans the schedule, controls the budget and supervises the team. The content specialist researches the subject matter, the script writer turns it into a script, and the text editor checks the text for correctness. The multimedia architect brings together text, graphics, animation, sound and video using authoring tools. The computer graphic artist creates the visuals, the audio and video specialists record and edit sound and video, and the computer programmer writes the code. The web master puts the finished site online and keeps it updated.

Where multimedia is used

In education, animations, simulations and virtual classrooms let students learn at their own pace. Businesses use multimedia for staff training, advertising, presentations and video conferencing between offices. In medicine, doctors practise surgical procedures on computer simulations before operating on patients. Entertainment uses it in films, games and music. Public kiosks in banks, railway stations, airports and museums give information through touch screens, and the ATM is the most familiar example. Products are delivered on CD or DVD or streamed over the internet, where slow connections cause buffering and missing plug-ins can stop media from playing.

Common mistakes to avoid

• Mixing up raster and vector. Raster means pixels, and quality drops when you enlarge the picture. Vector means shapes defined by formulas, and it scales without losing sharpness.
• Calling a MIDI file a sound recording. MIDI holds instructions for a synthesizer, not the digitised sound wave, which is why MIDI files are so small.
• Marking JPEG as lossless. JPEG is lossy: the detail removed during compression cannot be recovered. PNG is the lossless one.
• Getting the order of production steps wrong. Testing comes after production, and documentation comes after testing, just before delivery.

Test yourself on these with the practice test, then check the worked reasoning in the solved MCQs.

Frequently asked questions

What is the difference between raster and vector images?

A raster image is a grid of tiny coloured dots called pixels. It suits photographs, but when you enlarge it the pixels show and the edges look jagged. A vector image stores lines, curves and shapes as mathematical descriptions, so it can be resized to any size and stay sharp, and the file is usually small.

How does hypertext differ from static text?

Static text stays fixed on the screen, like a heading or a paragraph that explains a picture. Hypertext is made of nodes joined by links. The reader clicks a link to jump to related information, so the text can be read in any order instead of strictly from top to bottom.

Why is MIDI useful for multimedia developers?

MIDI is a standard way for computers and electronic instruments to communicate. A MIDI file stores instructions such as the note, its length and its loudness, not recorded sound. The files are therefore very small and easy to edit, which makes MIDI convenient for background music.

What are the steps in multimedia production?

There are twelve: conceptual analysis and planning, project design, pre-production, budgeting, multimedia production team, hardware and software selection, defining the content, preparing the structure, production, testing, documentation, and delivering the multimedia product.

What does a multimedia architect do?

The multimedia architect takes the separate pieces made by the team, that is the text, graphics, animation, sound and video, and joins them into one working interactive product using authoring software.

Why is testing done before a multimedia product is released?

Testing checks that every link, script and media file works as planned. A web-based product must be opened in different browsers, because a page that works in one browser may not display correctly in another. Fixing these problems before release saves users from a broken product.

What is a kiosk?

A kiosk is a computer terminal placed in a public place that gives information using text, graphics, video and usually a touch screen. You find them in banks, airports, railway stations and museums. The ATM is a well-known example.