Multimedia

Multimedia Industries

WJEC GCSE ICT

Starter

• Multimedia is the combination of different elements:

• Multimedia is used in many different places:

Sound Text Animation Video Interactivity

Education Entertainment Business Society

New Trends in Multimedia

• E-Book readers

• Smart phones

• 3D TV

• X-BOX Kinect

• Magazines with Video Ads.

• Tablet PCs (iPad etc.)

Multimedia in Education• Multimedia is everywhere in education.• How is each device shown below used?

Interactive Whiteboard Graphics Tablet Activ-Voting Sound

Video Smart Phones Tablet (iPad) Netbooks

Multimedia in Entertainment• Multimedia is everywhere in entertainment.• How is each device shown below used?

Digital TV3D TV Smart Phones iPod / MP3

Video

Games Consoles

Tablet (iPad) DVD Technology Digital Catch-up

Multimedia in Business• Multimedia is everywhere in business.• How is each device shown below used?

Smart PhonesPresentationSound

Video

VOIP Services

The internet Social Media

Multimedia in Society• Multimedia is everywhere in society.• How is each device shown below used?

Smart PhonesTraffic SystemsSound

Video

Public Information Systems

The internet Social Media GPS Systems

Multimedia Hardware

• Remember, multimedia takes up a LOT of space.

• It also takes a lot of memory and processing power to display and use multimedia on a computer – which can slow a computer down!

Screens• Screen size – Different sizes and uses (TV, Monitor, Screens etc.).

• Screen Resolution – Measured in pixels per cm – governs the quality. The more pixels the better the quality.

• TFT (Thin Film Transistor) & LCD (Liquid Crystal Display) – Light, cheap and do not take up a lot of space.

• Plasma – can be larger than LCD screens.

• (Don’t forget we now have LED screens, 3D, HD and Ultra High-Def)

Input Devices

• WHY are each of these needed and what do they do?

• Microphone

• Graphics Tablet

• Mouse

• Touch Screen

Sound Devices

• MIDI devices (Musical Instrument Digital Interface) A go between musical

devices and a computer.

Converts signals from a device (e.g. keyboard) into something the computer can understand.

DIGITAL CAMERAS AND DV CAMS

Megapixels explained

• The number of pixels in the image.

• The higher the DPI the closer the pixels are together.

• MP governs the SIZE more than he quality.

Camera TechnologiesDigital Cameras Digital Video Cameras• All stored digitally – no developing.

• A range of effects (red eye, steady shot, face recognition, geo-tagging, B&W, mosaic etc.)

• High optical zoom

• Can support HD, 3D and Video

• Direct posting to social networks

• Available in very high MP

• Can be stored digitally (DVD, SD etc.) or on tape.

• Can shoot in HD, 3D

• Can stream online

• Range of effects

• Can take pictures as well as video.

• High MP for shooting video

• LCD Preview screen.

But what about web cams?

• Good enough for using online.

• Can take simple pictures – limited effects.

• Low quality MP – but good enough for online.

• Used for instant messaging, remote meetings, video conferencing etc.

• Often built in to computers (laptops and Apples)

Interactive Components

Keyword Searches

Links

Why are they used?

Quizzes• Combines lots of different multimedia:

video, sound, text and images

• Can be created online and in software such as PowerPoint or Flash.

• Can be used to check learning, gain feedback or just for fun!

• Where would quizzes be used?

Questionnaires

• These can be used in a range of places to obtain feedback from a range of people.

Gaming

• Games use a massive array of multimedia.

• Intense sound, graphics and text are used with a lot of interaction with the user.

• Requires specialist, hi-spec hardware to cope with the level of graphics and processing speed.

What is good and bad about each method?

Multimedia How can it be stored (where does it come from)

Text • Typed into a word processing document.• Found online in web pages

Sound • Capture yourself in recording software• Mix yourself• Online libraries• CD’s etc..• Can be linked or embedded into multimedia – GOOD or BAD?

Graphics • Scan in from different places: books, magazines etc.• Find online• Capture yourself• Clip-Art• Draw them yourself in graphics software

Video • Capture yourself• Online• Video libraries

Animation • Capture yourself• Online• Make using online sites

Linking Vs. Embedding• Linking – This is where a multimedia product (e.g. game, presentation

etc.) finds the video, animation or sound and displays it. It is a separate file on the disk.

• Embedding – this is where the actual item is inside the product.

• Embedding makes the product MUCH larger, but does keep everything in one place. Linking keep all files separate making changes more simpler.

• An example would be that you can LINK or EMBED a video inside powerpoint.

• What is good and bad about these options?

Multimedia SoftwareAdvantages Disadvantages

Can combine images, text, video, sound etc.

Multimedia files can take up a lot of space.

Can provide interactivity (links etc.) Can take a long time to create files

Better than just displaying text Takes a lot of processing power

Allows for more creativity Games interaction can be addicting leading to other issues (remember unit 1).

Explains ideas more clearly.

Digital GraphicsVector, Bitmaps and DPI

Basics

• PIXEL a coloured dot in an image.

• BITMAP an image made up of pixels each having their own colour information.

• VECTOR IMAGE an image made up of shapes and lines.

• IMAGE RESOLUTION the amount of detail in an image.

Bitmap Images (AKA: Raster Images)

• Pixel based images• Location and colour information is stored

about every single pixel in the picture.• Individual pixels can be changed.• Resolution based. Stretching them,

stretches the pixels and loses quality.• Can be created in Paint, Photoshop etc.

Vector

• Mathematically based pictures. Made up of lines, shapes etc (objects).• Objects are independent of one another.• Have smooth edges.• Good for precise drawing.• Easily scalable (as they are not pixel based).• E.gs include JPEG (we will look at file types later)• Mainly used for photography / capturing real images.• Created in drawing programs such as Serif Draw, Illustrator or PhotoShop

The Difference Between the Two

Simply Put

• Which is a bitmap / raster?• Which is a vector?• WHY?

BMP Vs. Vector• Bitmaps – made of millions of pixels – massive files.• Vectors – uses maths to calculate shapes etc.

Vectors • can be stretched etc. without losing quality• Take up a lot less space than bmps• Used for things such as maps, guides, diagrams etc. – for precision.• Used on the web – for their fast download speed (small file size)• Portable – work in a wide range of software

Bitmaps• Can become blurred if over stretched• Large file sizes

Finally: DPI & Resolution• Resolution determines the image quality. The higher the resolution, the

better the quality of the image.

• Resolution is measured in DPI (Dots Per Inch).

• Determines the print / display quality of an image

• The more ‘dots’ (pixels) that an image is made up of, the better the quality (resolution).

• BUT: The more dots, the bigger the file size.

72DPI vs. 300DPI

• 72DPI – lower quality, but smaller file. Great for the web. Why?

• 300DPI – higher quality, large file. Great for printing. Why?

BackgroundsImages can have different background colours.

TRANSPARENT: - Nothing at all – like drawing on glass. No memory is used for the background – reducing the size of the image.

WHITE: All one colour background. Information only needs to be stored about the one colour – so some memory is used but not a great amount. Colour information only needs to be stored ONCE for the background.

COLOURED / DIFFERENT – Information needs to be kept about each part of the background as it is not the same throughout – meaning the image is significantly larger.

File Formats

• There are other file types… PSD, BMP, EPS and many more…

Image Description

JPEG Joint Photographic Experts Group:Default format for digital camera. Image quality can vary. Image size can be small, making it suitable for the web. Compatible with all web browsers. 16.7million colours – supports transparency.

TIFF Tagged Image File Format:A bitmap image format, similar to JPEG but not used online – web browsers don’t easily support it.

PNG Portable Network Graphics:Alternative to GIF. Supports 16m colours. Excellent for larger images, large file sizes though. Older web browsers don’t support PNG.

GIF Graphics Interchange Format:Limited to 256 colours. Not good for detailed images, more ideal for smaller items (logos, icons etc). Compatible with all web browsers. Supports transparency. Is compressed.

More File Formats

Image Description

PSD Photoshop Data FileLarge file – used in Photoshop. Keeps all data needed to edit an image: layers, edits etc. Used to produce final file (JPEG etc.).Very high quality – no compression.

EPS Encapsulated PostscriptCombines text and graphics.Rarely used for graphics – mainly for bitmaps

BMP BitmapsKeeps a map of all the pixels and colour information.Massive files

Data Compression and Optimisation

• Removing some content from a file which is un-needed to

reduce the file size.

• Removes parts of a file which are not necessarily accessible by a

human (visible/audible)

• This makes a file smaller, for sending or storage on a device.

Compression

200kb 87kb

• Any really, but some typical ones…

What files can be compressed?

soundmp3

image

video

jpeg

wmv

Advantages/Disadvantages to Compression

Advantages:• Faster uploads/downloads• Saves memory/storage (space) / saves hard disc space (Not ‘saves space’)• Ability to email some compressed files• File size smaller

Disadvantages:• Loss in quality / reduction in number of colours / becomes blurry• Slower access of compressed data / decompression needed when opening file• More resources intense when accessing compressed files

• Put simply optimisation is the reduction of a file size

• Files are often optimised in order to be put onto a website

• Optimised files, because they are smaller, load onto webpages more quickly and save memory space

• Optimised files can lose quality if the file size is made smaller

Optimisation

•Portable equipment (e.g. mp3 players, cameras etc.)•Website designers•Accessing a website• Fast copying of files

Why do we compress

Advantages Disadvantages

More files can be stored on a storage device. E.g. more images on a memory card.

Quality of the image will be poorer if compressed.

Time to put images on a website will be reduced.

Music can lose some quality

Time to access a website will be faster. Open to files being copied or downloaded quickly.

More music on portable devices.

Review

Image Manipulation Techniques• Zoom• Selection• Transforming• Sizing/enlarge/reduce size• Crop• Copying• Moving• Cloning• Brush settings• Layering• Red-eye removal• Spot clearing• Skew• Rotate• Distortion• Colour palette• Contrast• Brightness• Text• Blur• ………