12.m3 cms content-updating-pt3
- 1. IT2032PA Content Management System (CMS) Nitec in Social Media & Web Technology
- 2. CMS Content Updating In this chapter, you will learn: o Define what is “digital audio” o Identify the various sound formats and its characteristics o Describe the advantages and disadvantages of the various formats across platforms. o Define what “digital animation” o Identify the characteristics and file extensions of various animation formats. o Describe the advantages and disadvantages of the various formats across platforms.
- 3. Digital Sound A sound file format is simply a recognized methodology for organizing the digitised sound’s data bits and bytes into a data file. Audio in Macintosh o On Macintosh, digitized sound is stored as data files (file extension .AIF or .SDII Audio in Windows o Microsoft has established a common audio file format called the wave audio format (wav)
- 4. Digital Sound Working with audio in the Internet o Download the entire audio file o Let the audio file streams into the computer
- 5. Digital Sound Musical Instrument Digital Interface – MIDI Format o It is not a digital audio format but a form of music notation o Both Mac and Windows make use of MIDI files o A MIDI interface is built into many sound cards of the PC o MIDI sounds are typically stored in files with the .MID extension
- 6. Digital Sound Advantages of MIDI Format o it is a near universal playback o easy integration into existing HTML pages o MIDI sizes are relatively small (2 KB and 25 KB)
- 7. Digital Sound Disadvantages of MIDI Format o it uses entirely different method of producing sound o it is basically a music notation and not a storage format for digitized audio o it is limited to jingles, instrumental tunes and ambient synthesizer background sounds
- 8. Digital Sound Windows WAVE Format (.wav) o Developed by Microsoft and IBM and is the common audio file format used for Windows. o may be compressed or uncompressed o one of the common formats used to store and play audio data o it doesn't address compression
- 9. Digital Sound Aiff Format (.aiff, .aif) o stands for Audio Interchange File Format and was developed by Apple for storage of sounds o a flexible file format o allows the specification of arbitrary sampling rates, sample size, number of channels, and application-specific format chunks.
- 10. Digital Sound Snd Format (.snd) o The SND (Sound ) was developed by Apple Computer Inc. o SND files are not cross-platform o Not supported by all web browser
- 11. Digital Sound MP3 Format (.mp3) o Uses a compression ratio capable of bringing file sizes down to approximately a megabyte a minute o uses a lossy compression scheme o MP3 stands for MPEG 1 layer 3 o usually 10-12 times smaller than normal 44Khz 16-bit stereo wav files o MP3 files are the sound part of the MPEG video format
- 12. Digital Sound RealAudio Fomat (.rm, ram) o developed for the Internet by Real Media o also supports video o features true streaming technology o allows streaming of audio (on-line music, Internet radio) with low bandwidths o reduces significant file size reductions
- 13. Digital Sound Windows Media Audio Format (.wma) o is a relatively late entry into the field of proprietary audio formats o performs very good at lower bit-rates o produce quality indistinguishable from the original CD at 128 kbps o supported by most full-featured player programs o is royalty-free when incorporated into software that runs on the Windows platform o ASF is Microsoft's specification for streaming
- 14. Compression MPEG-1 Digital Audio Compression o Layer I – not commonly used and seldom discussed. o Layer II – used in DVD audio. o Layer III – commonly called MP3. It is a popular format for compressed music on the Internet.
- 15. Compression MPEG-2 Digital Audio Compression o adds multiple channels o provides backward compatibility with MPEG-1 decoders
- 16. Compression Dolby Digital Audio Compression o also known as AC-3 o chosen audio compression for the new digital television transmission o allows up to 5.1 channels of discrete digital audio to be compressed
- 17. Audio on the Web Benefits o communicate ideas through informative dialogue, narration and voice content o improve site navigation with sound effects o enliven the entertainment pages o provide background music to your presentation o online music sales and distribution of digitized audio clips
- 18. Streaming Media The Streaming Media is a powerful technical innovation 1. Compress a digital audio file 2. Breaking it into small packets 3. Sent one after another over the internet. 4. When the packets reached their destination 5. They are decompressed and re-assembled 6. Played by the user’s system.
- 19. Streaming Media Formats The widely used formats are: o RealNetworks’ RealAudio o MP3 o Adobe Flash o Microsoft’s Window Media o Apple’s QuickTime
- 20. Digital Animation Animation makes static presentation come alive.
- 21. Streaming Media Formats Animation is possible because of a biological phenomenon known as persistence of vision and a psychological phenomenon called phi
- 22. Streaming Media Formats Tweening o The series of frames in between the keyframes Frame Rate o is the frequency (rate) at which an imaging device produces unique consecutive images called frames.
- 23. Animation File Format Fli/Flc Format FLC - Animator Pro Flic Files o This is the main animation file format created by Animator Pro. FLI - Original Animator Flic Files o limited to 320x200 resolutions o file structure is very similar to that of a FLC file
- 24. Animation File Format GIF89 o allows multiple images to be put into a single file and then displayed as an animation in a Web browser o Allows for transparency
- 25. Animation File Format SWF (Small Web Format or Shockwave Flash) o was designed to deliver vector graphics and animation over the Internet o designed to meet the following goals: • On-screen Display • Network Delivery • Simplicity • File Independence • Scalability • Speed
- 26. Animation File Format MNG o is short for Multiple-image Network Graphics o designed to replace the animated GIF o designed to animate a series of JPG images in as complicated a way as possible
- 27. Animation for the Web HTML makes no provision for animation Animation using: o GIF89 o Adobe SWF o Java Script