Skill Area 325: Deliver the Multimedia content through various media Multimedia and Web Design (MWD)
325.1 Understanding of multimedia considerations for Internet (13hrs) 325.1.1 Analyze factors affecting delivery of multimedia contents over internet 325.1.2 Illustrate authoring models
Factors affecting delivery of multimedia contents over internet Multimedia can be delivered in multiple ways including through stand-alone CD ROM. With the fast development of the Internet, it is possible to delivery multimedia contents on the World Wide Web (www).
Factors affecting delivery of multimedia contents over internet (cont) Most multimedia files are normally big in size There are several factors that affects the delivery of multimedia contents over the Internet: 1. Bandwidth 2. File size 3. Compression 4. Streaming 5. Other relevant factors
Bandwidth Bandwidth refers to how much data you can send through a network or modem connection. They are usually measured in bits per second or bps. The more the bandwidth, the more information can be transferred within a given amount of time. A bandwidth regardless it be high or low rate at that time, if like a highway road, when they is less users using the bandwidth then transfer of data or information in this case multimedia contents will be at a faster time rate compared to more users using the same bandwidth.
File Size The bigger the file size the more heavy to be sent via the internet. However with a higher bandwidth, it will still be delivered at a faster time rate compared to a lower bandwidth. If a big file size is sent over a low bandwidth then delivery of multimedia contents will be at slower speed rate thus cause the file to be transferred to either lag or to the point where the file transferred can be stopped due to the slow speed. If file size is small den regardless the bandwidth speed it will take shorter time to deliver the multimedia contents over the Internet.
Compression Compression is the reduction in size of data in order to save space or transmission time. Content compression is as removing all extra space characters. This kind of compression can reduce a text file to 50% of its original. Due to compression techniques like extension or plug-in for browser, displaying media element over the net the possible.
Compression (cont) To deliver the contents over the Internet minimum requirements must be met: 1. Minimize the number of cast members 2. Use low- resolution images and sound 3. Use images that can be compressed 4. Do not use loops continuously
Streaming Streaming stands for the real-time transport of live or stored media (e.g. video, audio and any associated data) over the Internet, between the client and server computers. In the streaming mode, the content file need not be downloaded in full, but plays out while parts of the content are being received and decoded. The term real time means that the user receives a continuous stream nearinstantaneously (with a minimum delay) and that the duration of the transmitted and received streams is exactly the same
Streaming (cont) Streaming is the only technology that is capable of transmitting video and audio events across the Internet in real time, i.e. while they are happening. Multimedia expands from the PC onto new user platforms such as hand-held wireless devices, interactive television set-top boxes, games consoles, 3G mobile phones, etc.
Advantages of Streaming It can deliver live content such as a football match, a concert or a political speech as it happens. It provides random access to long movies. The streaming server can act as a remote video player and perform some VCR functions (e.g. skip back and forth, enable watching only a portion of a media production without downloading the whole film).
Advantages of Streaming (cont) It occupies no space on the user s hard disk. The user does not get a copy of the media file that stays on a streaming server. The user can save a media, but what is actually saved is the URL of the stream, the current point in the media s timeline and the user s settings (such as the sound volume level). It only uses the exact network bandwidth it really needs. If the streaming content exceeds the connection speed, some data packets get lost and the content may break up.
Advantages of Streaming It allows for streaming tracks (e.g. stock and news tickers) to be included in otherwise non-streaming content. It can benefit from using broadcast and multicast approaches (where one stream can be sent to many users). (cont)
Streaming Media Format There are more than a dozen formats for streaming audio over the Web. Widely used formats over the Internet are like RealNetworks' RealAudio, streaming MP3, Macromedia's Flash and Director Shockwave, Microsoft's Windows Media, and Apple's QuickTime. More recent entries that synchronize sounds with events on a web page, such as RealMedia G2 with SMIL and Beatnik's Rich Music Format (RMF). Also included are a host of downloadable formats, including Liquid Audio, MP3, MIDI, WAV, and AU.
Authoring models With all that is discussed about the delivery of multimedia contents, authoring tools and models are of course needed to transfer information via the Internet. There are two types of authoring model: 1. Application-based 2. Browser-based
Application-Based Authoring Model An application that allow users to create the multimedia and its contents from an application modeling tool. One of its benefits is that the application need no updates compared to a browserbased application. However, an updated version of the application may be required due to a higher specs requirement of the application (that wants to be displayed over the Internet) from the application to be able to be displayed via the internet.
Browser-Based Authoring Model Browser-based is a term that refers to any piece of software which runs inside a web browser. Developing a browser-based application saves software developers from having to create a front-end for their applications. This reduces development cost and time and allows the software developers to devote more resources to making their core applications better.
Browser-Based Authoring Model ADVANTAGES: 1. They can communicate over the internet 2. They don t have to be installed on every client computer However, this mode of communication is relatively slow compared to network speeds and when the database becomes large there will be performance problems with many web-based applications