1 / 19

SWE 423: Multimedia Systems

SWE 423: Multimedia Systems. Chapter 2: Media and Data Streams. The Term Multimedia. Multi Prefix From Latin “Multus” meaning numerous Media Root Plural form of the Latin word “Medium”. “Medium” is a noun meaning middle or center. The Term Media.

stacy-crane
Download Presentation

SWE 423: Multimedia Systems

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SWE 423: Multimedia Systems Chapter 2: Media and Data Streams

  2. The Term Multimedia • Multi • Prefix • From Latin “Multus” meaning numerous • Media • Root • Plural form of the Latin word “Medium”. • “Medium” is a noun meaning middle or center.

  3. The Term Media • Media: A means to distribute and present information • Text • Graphics • Pictures • Voice • Sound • Music

  4. Attributes of Media • Perception Media • Representation Media • Presentation Media • Storage Media • Transmission Media • Information Exchange Media • Presentation Spaces and Presentation Values • Presentation Dimensions

  5. Key Properties of a Multimedia System • Discrete and continuous media • Support of one type does not constitute multimedia (according to authors) • Independent media • Unlike video, one can have more than one type. • Computer-controlled systems • Video recorder is not sufficient • Integration

  6. Characterizing Data Streams • Distributed networked multimedia systems transmit continuous and discrete data • Data transmission characteristics: • Asynchronous • Synchronous • Isochronous

  7. Asynchronous Transmission • The sender and the receiver do not need to coordinate before data can be transmitted. • Two independent clocks (one at the sender and the other at the receiver) determine the start of each bit (bit synchronization)

  8. Synchronous Transmission • The beginning of transmission may only take place at well-defined times, matching a clocking signal that runs the synchronism with that of the receiver.

  9. Isochronous Transmission • The time interval separating any two corresponding transitions is equal to the unit interval or to a multiple of the unit interval. • Transmission rate “guaranteed” and jitter is minimized. • Significant instants of two or more sequential signals have a constant phase relationship.

  10. Characterizing Continuous Data Streams • This is in relation to audio and video transmission • Strongly and Weakly Periodic Data Streams • Variation of the data volume of consecutive information units. • Interrelationship of consecutive packets.

  11. Strongly Periodic Data Stream • Constant time interval • Minimum jitter • e.g. PCM encoded voice in telephone systems

  12. Weakly Periodic Data Stream • Duration of time intervals between neighboring packets is a function with finite period duration. • Time intervals between neighboring packets is not constant.

  13. Non-Periodic Data Streams • Other possibilities • e.g. mouse movement on white boards of the screen in video conferences

  14. Variation of the Data Volume of Consecutive Information Units. Periodically Regular e.g. MPEG Strongly Regular e.g. uncompressed audio/video

  15. Variation of the Data Volume of Consecutive Information Units. Irregular e.g. JPEG

  16. Connection between consecutive packets: Interrelated • No gaps in between • Maximal throughput and use of resources • e.g. ISDN channel transmitting audio

  17. Connection between consecutive packets: Non-Interrelated • Gaps between some packets • e.g. DVI-PLV encoded streams over FDDI

  18. Comparison

  19. Information Units • Logical Data Units • E.g. Video Data • Clips • Scenes • Images • Regions • Pixels

More Related