Multimedia Definition and Components

• Course: Multimedia Systems (CS208).
• Topic: Multimedia Definition and Components.
• Instructor: Dr. Maha Ghoneim.

What is Multimedia?

• The term "Multimedia" is derived from two parts: "Multi" from Latin "Multus," meaning numerous, and "Media," the plural of medium, referring to how information is distributed and presented.
• Multimedia combines text, graphics, sound, animation, and video delivered digitally and interactively.
• Multimedia devices are the electronic tools used to store and experience multimedia content.

Multimedia Components

• Text: Characters used to form words, sentences, and paragraphs, enhancing multimedia presentations when combined with other media.
• Image: Photos (taken by cameras) and pictures (drawings or artwork) created/taken digitally.
• Audio: Includes speech, sound effects, and music.
• Animation: The illusion of movement created through the rapid display of static images.
• Video: The recording, capturing, and processing of moving real picture frames.

Linear vs. Interactive Multimedia

• Linear multimedia programs are designed for sequential viewing, offering a passive experience with a predetermined start and end point, requiring no user interaction during playback.
• Non-linear (Interactive) multimedia gives the viewer navigational control to specify which elements are delivered and when, representing a non-sequential type.
• Interactivity arises from an interface or connection that allows user choices to influence variable outcomes, eliminating path restrictions and time constraints.

Hypermedia

• Hypermedia combines hypertext, graphics, audio, and video or Linked elements.
• Hypermedia presents a structure of linked elements for user navigation.
• Clicking an image to enlarge it, a word to hear its pronunciation, or a video to jump to a related article exemplifies hypermedia interaction.

Multimedia Applications

• Common applications include: Education, Home entertainment (Video on demand, Gaming), Marketing, E-shopping, Tourism, Medicine, and Electronic newspapers.

Multimedia Quality of Service (QoS)

• QoS represents requirements that guarantee user satisfaction, such as data transfer speed, receiver wait time, and data loss likelihood.
• Service parameterization is defined by ISO standards through QoS.
• The primary goal of QoS is to provide priority including dedicated bandwidth.
• The primary goal of QoS is to provide controlled jitter and latency required by some real-time and interactive traffic
• The primary goal of QoS is to provide improved loss characteristics.
• QoS requirements for multimedia have been addressed by groups like ITU, ETSI, and 3GPP.
• ITU's main contributions are in Recommendations F.700 (framework for multimedia services) and G.1010 (end-user multimedia QoS categories).

QoS Parameters

• Throughput (Bandwidth): Refers to the data rate supported by a network, measured in bits per second (bps); multimedia applications typically require high bandwidth.
• Delay: The time lag between signal departure from the source and arrival at the destination, ranging from nanoseconds to fractions of a second, with greater delays occurring over the Internet.
• Jitter: Variation in packet arrival times, caused by congestion, timing drift, or route changes; its significance varies depending on the multimedia application, with live presentations being less tolerant than pre-recorded playback.
• Loss: The amount of data that fails to reach its specified destination within a period, mitigated by providing dedicated channels/bandwidth or retransmission of data.
• Reliability: Essential for real-time multimedia applications needing consistent packet delivery; system reliability depends on network factors and is inversely proportional to the failure rate.