Your SlideShare is downloading. ×
  • Like
InetCh4-MultiMedia.ppt
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×

Now you can save presentations on your phone or tablet

Available for both IPhone and Android

Text the download link to your phone

Standard text messaging rates apply

InetCh4-MultiMedia.ppt

  • 1,024 views
Published

 

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
    Be the first to like this
No Downloads

Views

Total Views
1,024
On SlideShare
0
From Embeds
0
Number of Embeds
0

Actions

Shares
Downloads
16
Comments
0
Likes
0

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. Information Resources on the Web Part 3 - Multimedia Tutorial 4
  • 2. Images and Graphics
    • Graphics Interchange Format (GIF) :
      • older image format
      • good compression for small- or medium-sized files
      • .gif filename extension, usually
      • <= 256 different colors
      • widely used on the Internet for images that have only a few distinct colors
        • line drawings, cartoons, simple icons, and screen objects
  • 3. Images and Graphics
    • Animated GIF file :
      • combine several images into a single GIF file
        • special editor
      • browser displays with appearance of cartoon-like animation.
  • 4. Images and Graphics
    • Joint Photographic Experts Group (JPEG) :
      • newer file format
      • >= 16 million colors
      • good for photographs and continuous-tone art
        • images that do not have sharp edges
      • .jpg filename extension. usually
  • 5. Images and Graphics
    • GIF and JPEG formats offer file compression
    • Uncompressed graphics files
      • -- too large to transmit efficiently.
    • JPEG file compression is lossy .
    • lossy compression
      • -- erases some elements of the graphic.
      • The greater the level of compression , the more graphic detail is lost.
  • 6. Images and Graphics
    • More graphic image file formats:
      • Windows bitmap file format (.bmp)
      • Tagged Image File Format (TIFF) (.tif)
      • PC Paintbrush format (.pcx )
      • Portable Network Graphics (PNG) format (.png)
    • Windows bitmap , TIFF , and PC Paintbrush formats
      • all uncompressed graphics formats
      • avoid them -- too long to download.
    • PNG format newer -- not yet approved as a Web standard
  • 7. Images and Graphics
    • WebMuseum site -- fine arts
    • Search engines/Web directories -- improving image classification for databases.
  • 8. Sounds, Music, and Video
    • Sound or video clips
      • enhance information
      • often require software extensions to Web browser.
    • Software extensions , or plug-ins:
      • are usually available as free downloads.
    • Firms that offer media players for free
      • earn $ by selling encoding software to developers
      • earn $ by selling enhanced player software
  • 9. Sounds, Music, and Video
    • Computer needs sound card and speaker(s) or earphones to play an audio file.
    • Wave (WAV) format
      • digitizes audio waveform information at a user-specified sampling rate
      • can be played on any Windows computer that supports sound.
    • size of WAV files limits use on the Web to short, lower-quality audio information.
  • 10. Sounds, Music, and Video
    • MIDI (Musical Instrument Digital Interface) format
      • standard adopted by music industry for to create and read musical information.
      • digitally records information about each element of the sound, including pitch, length, and volume.
      • Easier to edit music recorded in the MIDI format
        • can manipulate individual characteristics of the sound precis ely .
      • much smaller than WAV files
      • often used on the Web
      • .midi or .mid file extension usually
  • 11. Sounds, Music, and Video
    • UNIX operating system’s audio file format
    • known as the AU format because file extension usually .au .
    • AU files similar size as WAV files to store same information.
  • 12. Sounds, Music, and Video
    • Streaming transmission :
      • server sends first part of file to browser
      • browser begins playing file
      • while browser is playing file, server sends next segment of file
      • popular for transferring sound and video files
      • can access very large audio or video files in much less time than download-then-play procedure requires.
  • 13. Sounds, Music, and Video
    • RealNetworks, Inc ., developed
      • RealAudio format for audio files
      • RealVideo format for video files.
    • Must download and install one of the real file players
    • file extension is .ra or .ram
    • RealNetworks formats compressed further – more efficient Internet transfer
  • 14. Sounds, Music, and Video
    • Older video file formats available on the Web
      • AVI (Audio Video Interleaved) format
      • QuickTime format
    • 1 minute of AVI or QT video and sound  file that is about 6 MB
      • too large to transmit over slower types of Internet connections.
    • International Standards Organization’s (ISO) Moving Picture Experts Group (MPEG)  series of standards for compressed file formats.
    • Lossy: technique deletes information file
      • result can deteriorate quality
  • 15. Sounds, Music, and Video
    • MP3 :
      • MPEG format’s audio track
      • somewhat lower quality than WAV format files
      • 90 percent smaller than WAV
      • popular when disk storage on personal computers dropped in price and CD writers (also called CD burners) became affordable for home use
      • CD might hold
        • 15 songs in WAV format (about 40 MB per song)
        • 150 popular songs in MP3 format (about 4 MB per song)
  • 16. Ethical and Legal Concerns: Sharing Audio Files
    • MP3 files smaller  easy to send by Internet
    • File sharing software – Napster, Kazaa, ...
    • File-sharing activity is unethical
      • deprives the creators of their rights to control distribution and to profit from their work.
    • File-sharing is also illegal in many countries, including the United States.
  • 17. Legal MP3 File Distribution
    • Portable digital music players with flash memory technology can store thousands of songs.
    • Sites now sell digital music in MP3 and other formats.
      • some charge per song
      • others charge a flat monthly fee
      • restrictions on the number of copies of each song
      • may restrict you from converting downloaded song files into other formats
      • may restrict types of devices you may play the song on
  • 18. Future of Electronic Publishing
    • Information can be spread more rapidly than ever, in large quantities, but with low required investment.
    • E-zines :
      • Web-based magazines
      • appearing on the Web in increasing numbers.
      • can focus on specialized, narrow interests
      • Usually managed by an editor
    • Blogs :
      • usually written by single person, expressing particular viewpoint
      • most focus on issues where people have strong opinions