Video. Using video  Carefully planned, well-executed video clips can make a dramatic difference in a multimedia project  Use video only when all other

Download Video. Using video  Carefully planned, well-executed video clips can make a dramatic difference in a multimedia project  Use video only when all other

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  • Video

  • Using videoCarefully planned, well-executed video clips can make a dramatic difference in a multimedia projectUse video only when all other methods (text, still images) are not enough; dont use it just because its possible

  • Obtaining video clipsShoot your own clipsBuy footage; this can be a nightmare since the licensing rights and permission may be difficult to obtainOn some projects you have no choice but to pay the price for required footageExample: Istockphoto

  • Some technical detailsLight is converted into an electric signal by a sensor called a CCDGood cameras have 3 CCDs (RGB)Component video is split into two separate chroma channels and a brightness channelComposite video has all signals mixed together and carried on a single cable

  • Broadcast video standardsNTSC: Used in USA, Japan and some other countriesPAL: Europe, Australia, South AfricaSECAM: France, Russia and few other countriesHDTV: High Definition TV. 16:9 aspect ratio.

  • Video compressionEven a small 10-second clip of full-motion video requires transfer of an enormous amount of data in a very short amount of timeOne frame of 24-bits requires almost 1MB of computer data, 30 seconds will require a one gigabyteFull-size, full-motion video requires that the computer deliver data at about 30MB per secondThis technological bottleneck is overcome using digital video compression schemes or codecs (coders/decoders)

  • Video compressionA codec is the algorithm used to compress a video for delivery and then decode it in real-time for fast playbackAll popular codecs employ lossy compression algorithmsPopular codecs: MPEG, Divx, RealVideo, DVI/Indeo, Cinepak

  • Typical filename extensionsavi - Audio Video Interleavemp4 - MPEG-4 Part 14 or MP4 file formatmkv & mka - Matroska Multimedia Containermpg & mpeg - Moving Picture Experts Groupflv - Flash Videowmv, wma & asf - Advanced Systems Formatmov - Apple Quicktime Movierm - Real Media File3gp - 3GPP Multimedia Filevob + ifo - Video Object & DVD Information File Wikipedia: Comparison of Container Formats

  • Video frames of MPEG compression

  • (Net videos, CD-ROM videos, oldish)(DVD, digital TV, HDTV)(multimedia, digi-tv, mobile)

  • (Edition software)(Post production software)

  • Use of video in multimedia(good video is illustrative)

    (use static video, near shots)

    (less than 1 min clips)

    (video is confirming and creates mental images)

    (divide long video into clips with interactivity)

  • Animation

  • Principles of animationAnimation is possible because of a biological phenomenon known as persistence of vision and a psychological phenomenon called phiAn object seen by the human eye remains chemically mapped on the eyes retina for a brief time after viewingCombined with the human minds need to conceptually complete a perceived action, this makes it possible for a series of images to blend together into a visual illusion of movement

  • Computer animationComputer animation programs typically use layers, keyframes and tweening techniquesThese methods are commonly used also with traditional animations that are done without computersYou can usually set your own framerate, but the rate at which changes are computed and screens actully refreshed will depend on the power of your display platform and hardwareThe smaller the object, the faster it can move

  • Animation file formatsSome file formats are designed specially for animations; they can be often ported among applications and platformsPopular animation formats: Director (.dir and .dcr), 3D Studio Max (.max), Windows Audio Video Interleave (.avi), Machintosh Quicktime (.mov), Motion Video (.mpg), Flash (.swf)

  • Video vs. animationVideo includes something that is real; an animation has no limits

    When to choose video, when animation?

  • (Animation software)

    , Blender.

    (Camtasia Studio, Captivate)

  • Example:2D Visualization of nuclear power plant components

    3D visualization of a wood pressing machine