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Dreamweaver Chapter 9 Multimedia Multimedia • Audio – Live recorded sound • i.e. movie theme songs, foreign language phrases – Attract interest – Share information • Guidelines – Make sure its clear – Limit the time it plays. i.e. when site loads Multimedia • Video is live or recorded moving pictures used to teach or entertain • Guidelines: – Video files are large – Use them to enhance not to convey a message – Not all people will be able to access it due to access issues (speed of download vs. size of file) Multimedia • Animation – Uses graphics or text to represent motion • Guidelines – Used to draw attention to important content – Limit animations • Too much is distracting File Size Guidelines • Larger the file = longer the download • Steaming media – Reduces user wait time – Web server breaks transmission into pieces – Users hardware plays first piece while the rest of file is downloading – Other pieces received by the player (i.e. real player, windows media player), are stored and played in order – The result is a continuous stream of content • Streaming requires CODEC (compression/decompression) software to compress and decompress data Multimedia Authoring Tools are Software Packages • Integrate media components such as audio, video, animation, and images into one project • Most widely used: – Macromedia Director Audio Applications • Create and edit audio files – GoldWave – SoundForge – Audacity Video Applications • Windows Movie Maker • Adobe Premiere Pro – Allows control over every frame – Supports more movie formats than wmv Evaluating Multimedia Sites • Do audio, video or animation support sites goals? • Are pages cluttered? • Does media distract? • Does site give option to skip? • Does sound and video work properly when page loads? • Does it take too long to download? • Does it enhance the site? Audio File Formats • .wav – wave format developed by Microsoft and uses a very short clip • .mid – Midi is used by synthesizers and electronics • .ram or .ra – Real Audio was developed by Real Networks • AIFF – Used by Macintosh • MPEG – Moving Picture Experts Group and can crate small, highly compressed audio files • Swf – Shockwave flash object developed by macromedia and requires a flash plug in to listen to or view Video File Formats • AVI – Windows media player must be downloaded before it can play • Mpg – Compressed and used for streaming • mov (QuickTime) – Developed by apple and can be used for streaming • RAM Real Video from Real Networks – used for streaming good for low speed connections • WMV Windows Media Video – can be used with Windows Media Player and used for streaming • swf Shockwave – Macromedia and requires a plug in Sampling • Digital recording devices capture sound by sampling a sound wave • Sound is captured in fragments • The fragments are reproduced and played together • The sampling rate is the number of times per second a device samples the sound waves • The higher the sampling rate the better the audio quality Video Sampling • Video clips are called frames and the rate they appear is measured in frames per second • Each single image in a video clip is a frame • Frames are measured in FPS( frames per second) – Internet video varies form 10 to 30 FPS – Slow frame rate can result in jerky video – Faster FPS results in better video quality Audio • Sound card and speakers – Required to play audio • Microphone and audio application – Required to record audio • Stored sound files – Can be edited with audio editing software Incorporating Sound on Page • Link audio file to a button – User clicks to play sound – Gives user control • Set sound file to play automatically – When page loads – Can play once or loop repeatedly • Best to play only when page is loading – Complete page 260 Activity 9A Creating and Adding Video • Video Recorder – Creates video • Two types of recorders – Analog • Data must be translated into digital format • Video capture card performs conversion – Digital (digital camcorder) • • • • Use cable to connect video to computer Transfer video to hard disk Video editing software edits video Video is inserted to page Challenges When Using Video • Large amounts of download time required • Different file formats require different CODECS to compress and decompress file data • Web browser must understand the files format and codec • Because of these challenges video is provided via a link not placed directly on page Try It • Page 262 Activity 9B Insert a Video Clip Animation Files GIF Macromedia Flash Individual Gif images displayed one after the other. All images are stored in a single GIF file. More sophisticated files that include interactivity and download more quickly Created with Fireworks, Image Ready Created with Flash Inserted like a GIF image Inserted like any file Requires a Flash plug in free from macromedia web site Extension=gif Extension=swf Try It • Activity 9C Insert an Animation Page 266 • Activity 9D Flash Buttons Page 267 Homework • Know terms and main ideas for test P269 • P270 Reviewing Key Terms #1, 2, 3, 4, 5, 6, 7 • P270 Understanding Main Ideas #11, 12, 13, 14 • P273 Challenge Yourself Compare Plugins