2Unit Outline In this unit, we will learn Animation Guidelines Flipbook Sampling Rate and Playback RateCel AnimationFrame-based AnimationPath-based AnimationComputational AnimationProgram-based or Script-based AnimationSpecial Animation EffectsAnimation SoftwareAnimation File Formats
3Introduction Animation is an illusion, a perception of motion. Animation: Simply a moving or changing graphic imageAnimation: A series of still images played back fast enough to trick our minds into believing that there is movementTo create the illusion of animation, a series of still images is displayed fast enough so the viewer believes the images are moving.
4IntroductionAnimation is an excellent way to increase appeal of a multimedia application and ensure return visits.Animation can be used to simplify complex concepts and visualize concepts.Animations can be simple, as in blinking text, marquee-like scrolling headlines, rotating logos, animated icons, Web buttons, 2-D action figures, 3-D action figures.4
5Animation Guidelines Animations should impact not detract. Self-Study SlideAnimations should impact not detract.Animate what we want users to notice.Animation should be appropriate to the mood and content of the application.Do not use too many animated objects per page.Animation that does the same thing over and over is annoying.Use transitions and special effects that help communicate message.Make sure animation loads quickly.
6Animation GuidelinesSelf-Study SlideUse animation where taking video shots may be unpractical or impossible but where depicting motion is necessary.Use animation where minute details are to be depicted.Video often has a lower resolution than animation.6
7Flipbook Digital animation is based on flipbooks. A flipbook is a book with a series of pictures varying gradually from one page to the next, so that when the pages are turned rapidly, the pictures appear to animate.Flipbook7
8Sampling Rate and Playback Rate Two rates are used to measure animation: sampling rate and playback rateSampling rate refers to the number of images created per second and available to be used in an animation.Playback rate is the number of frames displayed per second when animation is being viewed.Playback rate cannot be higher than the sampling rate.
9Sampling Rate and Playback Rate To create the illusion of motion effectively, the playback rate of animation must be between 24 and 30 frames per second at full-motion video standards.On the Web, the standard is generally 12 to 15 frames per second.Anything less than 12 frames per second, however, will create a jerky motion as the eye detects the changes from one frame to the next.9
10Cel Animation Images are drawn on pieces of celluloid. Celluloid images are placed on a stationary background.The background remains fixed as objects change from frame to frame.
12Frame-based Animation Computer-based cel animation is based on changes that occur from one frame to the next.Each keyframe is unique and illustrates a key event in the timeline of the animation. The difference between one keyframe and the next keyframe could be the result of a new position, color, shape, or any number of other characteristics or combinations of characteristics.Tweening: process of drawing “between’’ frames; requires at least two keyframes
13Path-based AnimationAlso known as vector animation; an animated object is created by following an object’s transition over a line or vectorInvolves the creation of one object and a path; then tweening is used to fill in the frames as the object moves along the pathWith path-based animation, the computer program manipulates the object by drawing the frames along the path that the object follows.
14Computational Animation Allows an object to be moved across a screen by varying its x- and y- coordinatesIs similar to path-based animation; however, instead of specifying a path for the object to travel, its position is varied based on axes
15Program-based or Script-based Animation Involves the use of programming / scripting languages to create animationAnimations created are often more flexible than those created using the other methods because they can be very easily modified to use new images and objects.
16Special Animation Effects Morphing: process of blending together two images into a series of imagesMorphing uses frames to create the illusion of one object changing into another.In Adobe Flash, morphing on simple vector graphics can be created by using a process called shape tweening.Morphing16
17Special Animation Effects Warping: Distortion of an image (only one image is used)Software can be used to distort or warp an image to create a special animation effect.17
18Special Animation Effects A film loop consists of a series of animated frames looped to play over and over again.Trail effect is when the image from the previous frame is not completely erased so that it appears in the new frame.
19Onion-skinning Is a common feature provided by animation software Enables animators to see previous and following frames while they are drawing the current frameOnion-skinning19
20Animation SoftwareSome animation software combine both bitmap- and vector-editing tools within a single environment.Animation software allow animators to import media elements of various file formats.Some animation software use a timeline for development and control.Some animation software has a built-in scripting languageExample: ActionScript in Adobe Flash20
22Animation File Formats Animated GIFAlso known as GIF89aRequires no plug-in for viewing in browsersIs supported by all major browsersSWFThis file format is for viewing onlyTo view SWF files, Adobe Flash Player must be installed on user’s computer.QuickTime (MOV)Apple’s animation and movie file formatIs non-platform specific
23Animation File Formats MPEG (Moving Picture Experts Group)Moving Picture Experts Group created standards for interactive animation and video.MPEG files tend to be much smaller and of much higher quality for the size since MPEG uses very sophisticated compression techniques.AVI (Audio Video Interleave)Microsoft’s animation and movie file format for WindowsAlthough AVI files are native to Windows, other programs and players will also recognize and play them.23
24ReferencePart of this slide set is prepared or/and extracted from the following book:Multimedia For The Web Revealed, Calleen Coorough & Jim Shuman, Thomson Learning, 2006, ISBN:This set of slides is for teaching purpose only.Self-study slide(s) is / are within the scope of the final examination.