asgment 1J

QUESTION 1 (a)

1.0 INTRODUCTION

The term streaming has become fairly broad in definition and now generally refers to media, such as video and audio, that is delivered over a network. The data associated with multimedia applications can be and usually is, quite complex. It can include text, images, 3D graphics, animation, video, audio and much more. A simple text message with voice annotation, video synchronized with voice (as in television) and an HTML document with embedded voice, video, images and data are all forms of multimedia.

Video on the web isn’t a new concept. Web pages have contained video and audio clips for years. But with commonly used formats, the video was downloaded in its entirety before viewing, a painfully slow process that was rarely worth the wait. The large file sizes of multimedia content necessitated that another method be deployed so that users can view or listen without long download times.

One solution was for multimedia files to be transmitted via the same method as standard web content, with the exception that the file was broken into smaller pieces so that playback could begin before the entire file reached the end-user’s desktop. In this case, multimedia content is viewed with a plug-in component that has been incorporated in the browser. This kind of video viewing is called progressive downloading, also referred to as progressive streaming, HTTP streaming or pseudo-streaming. Examples of this technology include Flash, Shockwave, AVI files and MPEG formats such as MP3 files.

“Real-time streaming” builds on the concept of progressive download, allowing a multimedia signal to be transmitted for viewing after only a momentary delay for data buffering. Real-time streaming reduces startup time and eliminates the need for significant on site storage capacity by buffering only that part of a stream that has not yet been viewed. Effective transmission of these video signals over low bandwidth facilities requires a high data compression rate in order to smooth out the quality of the visual presentation. Real-time streaming uses specific protocols and delivery formats that can understand the condition of the network and adjust transmission rates so that the client will receive the content even if the quality is degraded.
Real-time streaming requires streaming-specific media servers. Vendors of streaming media server software use proprietary methods for data compression, synchronization, format and bandwidth management, so users must download a player for each streaming media data type they want to access. The most common streaming media vendors are Real Networks, Microsoft Media Services, and Apple QuickTime.

There are several ways of delivering streaming media content. A video information source may be either live or on-demand. For live content, the data is captured, transported and displayed while the event is happening. On-demand content, also referred to as Video on Demand or VoD, is recorded beforehand, then stored and viewed at the clients leisure. VoD technology is similar to a common Video Cassette Recorder (VCR), users can stop, pause, rewind, fast forward, and play.
Streaming Method Video Support Network Traits Applications


2.0 HOW DOES STREAMING MEDIA WORK?
Streaming is all about compromises. Raw video content, with all its color, detail and sound, consumes a great deal of bandwidth. For example, a typical television show produces millions of pixels changing every second. To make that same show available on a PC, a computer would have to transmit all of the information for each pixel across the Internet. At the receiving end another computer would have to transform that information into pixels for display, keeping track of changes to the display in real-time. Raw (uncompressed) video contains too much information for limited computer and network systems to handle.
The quality of a multimedia presentation is an important end user issue in video and audio systems. Jerkiness or fuzziness in video playback, drop out rates and fidelity of sound reproduction represent measures of quality, just as completeness and accuracy do for text and binary files. In addition, the viability of a multimedia data service depends on the cost and capabilities of the networks, processors and media databases. Architectural tradeoffs between the quality of service, the costs incurred and the resources assigned will always be necessary.

2.1 Streaming Media consists of five end-to-end elements:

Ø Production
Ø Encoding and publishing which create and edit multimedia content
Ø Streaming Servers where content is stored and from which content is served to clients
Ø Network Infrastructure for content delivery
Ø Streaming Players which allow the content to be viewed from the client’s PC






2.1.1 Production
Producing streaming media content is very similar to producing a traditional video. The process can be broken down to three areas:

Ø Pre-production deals with the scope of the video. An important pre-production task is making the decision between live or on-demand format
Ø Production is actually shooting the video
Ø Post-production deals with the process of digitizing the video for “streaming media” delivery

Content is typically filmed using a standard digital video camera. The output of the camera is fed into a video and audio capture board located in the encoding computer.

2.1.2 Encoding
Encoding compresses video files into specific formats using mathematical formulas to compress the video data at the source and to decompress that data for video display at the receiving end. Compression technologies not only relieve bandwidth requirements but also processing requirements, which can become very intensive for large files for pieces of files.

Both live and on-demand content can be encoded. Encoding on-demand content consists of taking file output that has been stored on the encoding computer and compressing the entire file at once. Live content is encoded “on the fly” while the event or broadcast is happening.

When encoding streaming content, it is important to understand the “bandwidth” that the viewer population will have available for viewing. Typically end-user bandwidth capability is broken into three groups:

Ø Narrowband is often defined as access only up to 56kb/s. While this is the largest population today, a rich broadcast media experience is hard to achieve in this environment.
Ø Midband refers to access speeds between 128kb/s to 256kb/s.
Ø Broadband refers to higher access speeds available from cable modems, DSL (Digital Subscriber Lines) and direct LAN or high-speed WAN connections. Broadband access is typical in enterprise networks and is rapidly growing for remote users as DSL and cable modem service becomes more common

Encoding software uses a codec (short for compressor-decompressor) to compress files for transmission and decompress files for viewing on an end-user’s machine. Most streaming media products use proprietary methods for data compression, synchronization, format and bandwidth management, so users must download a player for each streaming media data type they want to access. The most popular codecs are from RealNetworks (RealVideo8 Codec), Media 100 Sorenson Video Codec, Apple Video Codec and Microsoft Media Encoder.

Since most connections (including DSL and cable modems) do not have the capacity to deliver pure, uncompressed CD-quality audio or film quality, file compression is a critical aspect of streaming media delivery. For example, a one minute playback of CD-quality audio requires 10MB of data, approximately enough disk space to capture a small library of books or a 200-page website. Without compression, a 24-bit color video, with a 640 x 480 resolution, at 30 frames per second, requires an astonishing 26 megabytes of data per second. To put this in perspective, a 2 hour “feature” film would consume around 25 Gigabytes. In contrast, QuickTime encoding, could compress such a file to 700MB, RealNetworks’ encoding process would produce a 250MB file. Of course this is approximate based on frame rate, resolution and other factors.

Basic parameters for encoding include:
Ø Target Bit Rate – The target bit rate is set lower than the ideal bit rate for the connection. For example, 56Kbps modems can only achieve 53 Kbps of actual throughput. Many encoding technicians will target 42Kbps or even 36Kbps for these users. For midband connections the target is usually set between 80 and 100Kbps. Finally, even though broadband connections can generally support 1MB bit rates, the typical rate is set at 300Kbps since broadband users often must share a connection with several others.
Ø Audio vs. Video Bit Rate – When encoding, the audio and video streams are encoded separately. By necessity, video requires much more of the bit rate than an audio signal. Most codecs will select the optimum encoding for the audio when based on a selected video bit rate.
Ø Image Size – Scaling down the frame size is one of the best ways to lower bit rate requirements. Most 56Kbps streams will use a 160x120 or 176x120 image size. Larger frame sizes are generally expected at broadband rates and are usually 240x180 or 320x240

Streaming Media Formats
There are many different file formats. A media file format might be something like a BMP picture file, an AVI video file, or a AIFF audio file. It holds the information used to describe a sound or a picture in a special known format. For example, the start of the file describes the color of the picture, the middle of the file describes the brightness of the picture and the end of the file describes the dimensions of the picture. There are two types of file formats, those that require complete download before viewing and those that can be viewed prior to completing download (streaming). Streaming file formats are specially encoded to enable viewing prior to downloading the entire contents. Streaming file formats also include information on timing, compression and copyrights.

2.1.3 Streaming Media Servers
There are two major approaches for streaming multimedia content to clients. The first is the server less approach which uses the standard web server and the associated HTTP protocol to get the multimedia data to the client. HTTP delivered clips can be prepared for progressive download, in which the clips will begin to play as soon as enough data has been delivered to the receiving computer’s hard drive. The second approach is the server based approach that uses a separate server specialized to the video or multimedia streaming task. The specialization takes many forms, including optimized routines for reading large multimedia files from disk, the flexibility to choose from multiple protocols types such as UDP/TCP/HTTP/Multicast to deliver data and the option to exploit continuous contact between client and server to dynamically optimize content delivery to the client.




Streaming Media Control Protocols
Streaming media protocols are a higher level client/server protocol for controlling the efficient delivery and quality of service of a media stream. Streaming Media Control Protocols provide methods to include common video controls such as stop, pause, rewind, and fast-forward as well as provisions for security, usage measurement and rights management so that streaming content providers can control their content and derive revenue by charging usage fees. The IETF standard streaming media protocol today is Real-Time Streaming Protocol (RTSP), but RealNetworks and Microsoft have built proprietary streaming media control protocols, Real RTSP G2, Real Progressive Network Audio (PNA), Microsoft Media Service (MMS).

Streaming Packet Formats
Streaming Media data has different transmission requirements and constraints than traditional Web (http) data. Most transmission protocols, such as TCP/IP, specify that the receiving station send an acknowledgement when the data is received. When not all data is received, the receiving station issues a request for the data to be re-sent. This method cannot be implemented for real-time streaming because of its time-dependent nature. Playback of audio or video is disrupted while the receiving station issues a request for the missing packets. Also, by the time the missing packets are re-sent, the scene requiring the packets will have already been viewed.

In order to deliver the streaming media to the client, the server takes compressed files from the encoder and breaks the file into smaller packets for delivery to the client. Streaming packet formats add header information to transport protocols, typically over UDP (User Datagram Protocol), though TCP (Transmission Control Protocol) and HTTP (HyperText Transfer Protocol) are sometimes used for reliable transport or to stream across firewalls that discard UDP packets. The information added to the transport header provides the basic functionality for transferring real-time data over packet networks such as source identification of origin streaming server, payload type identification which identifies the appropriate decoding and playback information to the client, sequence numbering for ordering packets and detecting losses, and time-stamping to control the playback time and measure jitter. This enables multiple media streams such as video, audio, and graphics to be properly synchronized with each other as well as for the packets to be re-assembled in the right order at the receiving destination.

Streaming Media Delivery Formats
Streaming Media servers can use Streaming Media Delivery Formats to integrate different media types and optimize delivery over disparate network infrastructures. A media delivery format does not describe the audiovisual data and it does not provide a method for encoding. Rather, the media delivery format is the unique way that audio-visual data is arranged into a single file. The file is created through scripting, like an HTML page, and contains information about timing, stream synchronization for multiple stream types, copyright and ownership, presentation layout and event information. The files that are incorporated into the media delivery format may be located in the same file or location or in a separate file or location, but the media delivery format will contain the synchronization information that the streaming media player will need in order to play the right files at the right time.

Ø Advanced Streaming Format (ASF) is Microsoft’s media delivery format. An ASF stream can contain a number of independent multimedia streams, such as a stream of MPEG compressed video, a stream of Real audio and any other streams for that are required for a complete presentation. Even though different media types may be able to be played back independently, the ASF splits up these independent formats and nests them within its own format. At the beginning of every ASF file is a header object describing the properties of the media streams held inside the ASF file. These properties include what kind of formats are involved, how these formats are arranged, the relationships between streams and other file information such as copyright and ownership. The data itself is stored after the header object, arranged in the way that the header object defines. It does not matter where the actual files are kept as long as the ASF properties describe the correct locations. An ASF file is invoked via a text link or an object on a web page. To create a link to an ASF file from a web page, editors create a corresponding “asx” file.

Ø ASX, WVX and WAX Files are Windows Media metafiles — simple text files that act as links from Web pages to Windows Media-based content on a Windows Media server or Web server. The basic purpose of a metafile is to redirect streaming media content away from the browsers, which cannot render the content, to a Microsoft Windows Media player. The metafile contains a type of Extensible Markup Language (XML) scripting that can only be read by the Windows Microsoft Media Player. A metafile script can be very simple or very complex. The most basic metafile contains simply the URL of some multimedia content on a server. A complex metafile can contain multiple files or streams arranged in a play list, instructions on how to play the files or streams, text and graphic elements and hyperlinks associated with the elements on the Windows Media Player interface.

Ø Synchronized Multimedia Integration Language (SMIL) is used by the Real Player G2. SMIL differs from Microsoft’s ASF in that it does not actually contain the audio-visual data in the same file. SMIL is like HTML, a markup language that defines which streams are playing at what time and of what type. The SMIL file contains layout, event and timing information of a presentation and even language options for the multimedia content. SMIL can also be used to incorporate interactive elements such as hyperlinks and buttons into streaming multimedia content.

2.1.4 Network
The network transport layer that delivers streaming content is different than that used for non-streaming content. While both transport protocols are based on IP (Internet Protocol), non-streaming content uses the Transport Control Protocol, or TCP a connection-oriented transport protocol. A file successfully transmitted over TCP, a logo for example is always identical to its source, although the time required for transmission may vary widely depending on infrastructure and network conditions between client and server. As a result, streaming content is best suited to a “connectionless” protocol. Streaming media typically uses UDP (User Datagram Protocol), with which IP packets are sent from the server to the client without establishing a connection that checks to ensure that each packet is received without errors. This protocol enables streaming media’s real-time nature since there is no need to wait to resend dropped packets. However, it also means that the content quality may be degraded markedly between server and client or that two different users may have a much different experience if the network between client and server degrades.

Streaming media also can be used in multicast and unicast environments. Unicast is a one-to-one connection and works with TCP and UDP for transport. Unicast enables users to watch what they want, when they want with complete control by using separate media streams for each client request. Since every user typically has to go to the origin media server to view streaming media content, this often consumes too much bandwidth in the network and/or overload origin media servers, especially when a large number of users try to view the same content at the same time. Since network and server capacity is already under great strain, this problem will likely only worsen as the use of streaming media and broadband networks expands.

Stream Thinning
Streaming-media vendors have tried to build in resiliency to overcome some of the performance hurdles of streaming delivery. When an end-user connects to a streaming server, there is constant negotiation between the server and the client software to decide what the server should actually send. If there is a connection problem or not enough bandwidth to deliver the stream as the content provider intends, the server will actually scale back or “thin” the stream. This allows the server to avoid dropping packets. Thinning can also occur in reaction to geography (distance) and time and is effected by the location of remote streaming servers. For example, a live broadcast that is delivered to 10 different cities could result in audiences in 8 of the cities receiving the broadcast as it was intended, but the audience in the last 2 cities receiving only half of the video bandwidth and frames per second due to congestion at peering points in their network route. Both RealNetworks and Microsoft have added additional functionality to help with congestion. RealSystems’ G2 congestion technology, SureStream, drops the client’s bit rate until thinning becomes necessary. When network congestion eases up, RealSystem G2 is able to dynamically increase the bit rate back to the client.

2.1.5 Streaming Player (Client)
Streaming Media content is accessed through specialized client software. This software generally runs on a PC, but could also run on an Internet-enabled device, such as a wireless PDA or cell phone. The client decodes, or decompresses the video or audio stream for playback. When receiving a stream, these clients “wait” a few seconds before actually playing the intended content, this is called buffering. Since the time necessary to decompress the audio and video vary, buffering in the application ensures that the audio and video data are synchronized for playback. The buffering process places the data in a buffer, once the buffer is full, the player software can be playing one packet, decompressing another and receiving the third. The buffer allows for the media to continue playing uninterrupted even during periods of high network congestion. Even though buffering technologies help with performance, the client often will still experience packet loss. It is not uncommon for packets to be lost or delayed along the way. Late packets are packets that the client receives into its play buffer too late to use. This is actually the worse case of all because these packets use up bandwidth and take up space in the client’s buffer that could otherwise be used for forthcoming packets. Lost packets never even make it to the client. Both late and lost packets can produce undesirable effects on audio and video, including pixelation, jitters, frozen video, audio popping, or audio static residing on their personal computers.

Finally, since streaming media products use proprietary methods for data compression, synchronization, format and bandwidth management, users must download a different player for each streaming media data type they want to access. The only exception is that all players will support content that has been created with standard RTSP/RTP streaming formats (though these formats have yet to see widespread use). The most popular players are Real Player, Microsoft Media Player and QuickTime.















3.0 Conclusion

Streaming technologies are rapidly gaining popularity as a way to deliver dynamic media over the Internet. As bandwidth increase and compression technologies mature, it becomes increasingly easier to deliver real-time, dynamic media, such as video, audio, animation, Java applications and 3D and vector graphic, using streaming technologies. If used properly, streaming applications can add impressive capability to your site.

Streaming technologies offer many business opportunities, such as corporate communications to internal and external audiences, distance learning and live events. Since the data associated with streaming media is too large for delivery over Internet infrastructure and must be compressed into smaller files, delivering streaming media is often a matter of making compromises.




























QUESTION 1 (b)

Current Problems with Streaming Technologies
There are a number of issues still need to be addressed in the current streaming marketplace including:
1.0 TechnologyA streaming media system is made of many interacting technologies. Video cameras and audio recorders create raw media. Editors use composition tools to combine raw media into a finished work. Servers store media and make them available to many people. Clients retrieve media from servers and display them to the user. Servers and clients store media in various file formats, they send and receive them in various stream formats. Servers and clients communicate over computer networks, using agreed upon network protocols. Servers encode media into a stream for transmission, clients receive the stream and decode it for display. Codecs perform the encoding and decoding.
In general, multimedia content is large, such that media storage and transmission costs are still significant to offset this somewhat, media are generally compressed for both storage and streaming. A media stream can be on demand or live.
2.0 Streaming bandwidth and storage
Streaming media storage size (in the common file system measurements mebibytes, gibibytes, tebibytes, and so on) is calculated from streaming bandwidth and length of the media with the following formula (for a single user and file):
Storage size (in mebibytes) = length (in seconds) · bit rate (in kbit/s) / 8,388.608 (since 1 mebibyte = 8 * 1,048,576 bits = 8,388.608 kilobits).
Real world example:
One hour of video encoded at 300 kbit/s (this is a typical broadband video for 2005 and its usually encoded in a 320×240 pixels window size) will be:
(3,600 s · 300 kbit/s) / 8,388.608 = 128.7 MiB of storage if the file is stored on a server for on-demand streaming. If this stream is viewed by 1,000 people, you would need:
300 kbit/s · 1,000 = 300,000 kbit/s = 300 Mbit/s of bandwidth
This is equivalent to 128.7 MiB per hour.3.0 Protocol issuesDesigning a network protocol to support streaming media raises many issues. Datagram protocols, such as the User Datagram Protocol (UDP), send the media stream as a series of small packets, called datagrams. This is simple and efficient, however, packets are liable to be lost or corrupted in transit. Depending on the protocol and the extent of the loss, the client may be able to recover the data with error correction techniques, may interpolate over the missing data or may suffer a dropout. The Real-time Transport Protocol (RTP), the Real Time Streaming Protocol (RTSP) and the Real Time Control Protocol (RTCP) were specifically designed to stream media over the network. They are all built on top of UDP.
Reliable protocols, such as the Transmission Control Protocol (TCP), guarantee correct delivery of each bit in the media stream. However, they accomplish this with a system of timeouts and retries, which makes them more complex to implement. It also means that when there is data loss on the network, the media stream stalls while the protocol handlers detect the loss and retransmit the missing data. Clients can minimize the effect of this by buffering data for display.
Another issue is that firewalls are more likely to block UDP-based protocols than TCP-based protocols. Unicast protocols send a separate copy of the media stream from the server to each client. This is simple, but can lead to massive duplication of data on the network. Multicast protocols undertake to send only one copy of the media stream over any given network connection, i.e. along the path between any two network routers. This is a more efficient use of network capacity, but it is much more complex to implement. Furthermore, multicast protocols must be implemented in the network routers as well as the servers. As of 2005, most routers on the Internet do not support multicast protocols and many firewalls block them. Multicast is most practical for organizations that run their own networks, such as universities and corporations. Since they buy their own routers and run their own network links, they can decide if the cost and effort of supporting a multicast protocol is justified by the resulting bandwidth savings.
Peer-to-peer (P2P) protocols arrange for media to be sent from clients that already have them to clients that do not. This prevents the server and its network connections from becoming a bottleneck. However, it raises technical, performance, quality, business, and legal issues.
Newer camcorders stream video to a computer over a FireWire connection. This uses a system of time-based reservations to ensure throughput, and can be received by multiple clients at once.
4.0 Social and legal issuesSome streaming broadcasters use streaming systems that interfere with the ability to record streams for later playback, either inadvertently through poor choice of streaming protocol or deliberately because they believe it is to their advantage to do so. Broadcasters may be concerned that copies will result in lost sales or that consumers may skip commercials. Whether users have the ability and the right to record streams has become a significant issue in the application of law to cyberspace.
In principle, there is no way to prevent a user from recording a media stream that has been delivered to their computer. Thus, the efforts of broadcasters to prevent this consist of making it inconvenient or illegal or both.
Broadcasters can make it inconvenient to record a stream, for example by using unpublished data formats or by encrypting the stream. Of course, data formats can be reverse engineered and encrypted streams must be decrypted with a key that resides somewhere on the consumer's computer, so these measures are security through obscurity, at best.
There are several issues that must be addressed when considering streaming media. The following agenda will give you a greater understanding of the issues related to streaming in order to make streaming media a successful technology.
i) Knowing Your Audience
Determining which direction you take with streaming technologies requires that you have some knowledge about the audience for your content and the technology infrastructure in which it will be delivered. If you have a user community that is primarily dial-up, then you have limited options and a low bandwidth solution might be in order. If you have a closed intranet community within your company and have high speed data networks to the desktop, you more than likely can stream much higher quality content. These characteristics of your audience all reflect on the preparation of the material you will stream to your users and how it must be optimized for that community of users that you serve. The situation gets much more muddled when you don’t have a clear understanding of the audience. In this situation, you might develop a strategy that will provide different resource at varying degrees of quality.
ii) Compression
Now that you know your audience and the infrastructure, you need to reduce file sizes so that they work for a modem or LAN and this is where the idea of compression comes to light. The goal of streaming compression is to throw away data that you don't need. This makes the file size much smaller. But be careful, if reduced too far, it begins to degrade the image and sound quality. Software compression/decompression is a rapidly evolving and competitive industry, thus much of the work has taken place outside the standards bodies and still remains proprietary in nature. Because of the evolving nature of this industry, advancements are still radically changing the character of the marketplace and quality of the compression continues to improve dramatically as a result. The process for delivering the dynamic content (audio, video, and graphics) is generally achieved through the use of a codecs. The term codec is short for compressor/decompressor. Codecs can be implemented in a variety off ways in hardware, software or both. Some popular codecs for digital video are MPEG, Indeo and Cinepak. On the Web, codecs are typically implemented as software plug-ins that add functionality to your browser. Plug-ins such as Apple’s QuickTime player, Microsoft’s Media Player, Real’s RealPlayer and MacroMedia’a Shockwave Player are examples of some of the major plug-ins that currently have wide acceptance on the Internet. Generally, these player are built in such a way that they will support a variety of different formats.

iii) Bandwidth Considerations
Bandwidth also will play an important role in how you develop content for streaming. Generally, the more bandwidth available the better the quality. Thus, if your know your typical user has a 28.8 modem connection, the quality of the content that will be streamed, particularly video content, will be quite low. This means so much data will have to be thrown away in the compression process, that the resultant stream will need to be very small file. This is typically considered a low-quality stream. Thus a low-bandwidth connection of 28.8 kbs or less would be considered a low quality stream. On the other side of the equation, if you have dedicated networks with lots of capacity, you will be able to serve and stream high-bandwidth files. High-bandwidth, or high-quality stream files, would be files that typically would be above 300 kbs. With high-capacity networks, it is possible to serve MPEG 1 files, which give full-screen, full-motion video comparable to standard television.
iv) Type of content
The type of content also determines how successfully you will be able to streaming the content. Typically, video is the most problematic because the sheer size of the data files. On the other hand, other types of content such as high-quality audio and vector graphics, might yield perfectly acceptable streams of high-quality content at 28.8 connections speeds. Another area where type of content might also be a factor is how it is produced initially. If the content is very dynamic in nature, it is very difficult to achieve good quality. This is a major factor in the compression of video for streaming. An example of this might be the difference between a talking head video and something dynamic like video footage of a football game. In the first instance, there is very little that changes in the video frame but the mouth and the head, thus high levels of compression can be achieved because most of the frame image is static and unchanging between frames. The compressor is only looking at the changes between the frames of video. But in the second example of the football game, the camera is panning the players are moving in every direction and thus the video compression between frames is very poor caused by the changing nature between the frames.
v) Quality of Service
Another area where streaming media delivery has a major impact is in the area of Quality of Service (QoS). Quality of Service refers to the ability to get service without interruption. Logically, the more streams you are serving the more saturated you networks become. Likewise, the higher the quality, the bigger the file sizes and again the more saturated the networks become. Thus, the whole area of QoS becomes an issue as your streaming applications impact other mission critical services. With this in mind, the highest quality streaming video may not necessarily be the best solution to implement if network capacity is already stressed. Alternative delivery strategies sacrifice the highest quality for lesser quality to support a larger community of use. It might also be advisable to consider different strategies that conserve network capacity.














QUESTION 2
1.0 Introduction
The news industry is currently undergoing major transformations as a result both of the growing popularity of the Internet itself and of advances in interactive multimedia technologies for the Internet. The types of news sources available on the Internet include newspapers, news wires, cable television, news magazines and radio stations. New technologies for the Internet include animations, direct manipulation of graphical interfaces and real time on-demand audio and video.
The shift from paper to electronic delivery of news occurred almost simultaneously with both producers and consumers of news. The number of Internet users has been debated widely but current estimates range from 10 million to 22 million Internet users and 11 million to 17 million WWW users. The number of newspapers online has grown from 20 in 1993, to 100 at the end of 1994, to over 800 at the start of 1996. At this rate of growth, there will be 1,500 to 2,000 newspapers online by the end of 1996. A recent Canadian survey of 197 news organizations showed that 38% of them were hooked to the Internet in 1995, and another 56% were planning to go online in the next 12 months. Vincent E. Giuliano of the Electronic Publishing Group has reported that the circulation of newspapers has declined since 1990, with the newspaper share of advertising slipping from 50% in 1930, to 27.6% in 1980, to 23.6% in 1993. During recent years, the electronic services industry has grown at a rate of 10%.
The amount of information stored on electronic news repositories is increasing very rapidly. Without an effective organization of information and design of the user interface, users will become lost and confused in the vast amounts of information.
2.0 Interactive Multimedia Technologies
Online interactive multimedia has greatly increased the popularity of electronic newspapers, particularly with the younger age groups, which have shown in recent years a significant decreasing interest in print-based newspapers. Currently only 52% of 18 to 24 year olds read daily newspapers, compared to 71% in 1967. The average age of readers in many large newspapers is over 50, which has motivated many newspaper organizations to move toward electronic delivery methods and seek new markets.
Multimedia news can contain images, sounds and movies. The most recent advance is the development of interactive multimedia technologies such as Shockwave by Macromedia Inc. and Java by Sun Corporation. These technologies incorporate images, sound, video, animations and user input into multimedia applications. These applications (also known as applets) are downloaded from a WWW server and provide interactions similar to that found on current CD-ROM implementations. Many of these technologies can be incorporated into WWW browsers with plug-ins, software modules that can be defined to process particular types of files that are downloaded as part of a WWW page.
Radio and televisions stations are also making their broadcasts available on the Internet with on-demand multimedia technologies. On-demand audio technologies, such as RealAudio or TOOLVOX by VOXWARE, can begin playing a sound file as it is being downloaded. On-demand video technologies such as VDO Live can begin playing a video file as it is being downloaded as well. The use of images, audio and video can increase the impact and perception of news. Examples of recent news events delivered with multimedia on the Internet include:
Photos of Yitzhak Rabin (Nando).
Video Re-enactment of Yitzhak Rabin's assassination (CNN).
Multimedia Coverage of the O.J. Simpson Trial's Finale (CNN).
Images of Nicole Simpson, photos and animations of the murder scene, photos of her bruised face, and her 911 phone call (aiff format) to police (CNN)
SuperBowl Photos and Video Replays (Nando).
Hearing Nicole's distressful voice in her 911 phone call and seeing the crime scene can be dramatically different than reading about it. However in many cases the electronic medium has not been used fully, appropriately or effectively used. The following section of the paper discusses diverse sources of multimedia news. Subsequent sections present design guidelines for interactive multimedia news.
3.0 Delivery of News on the Internet
The range of delivery styles and news sources on the Internet is wide encompassing newspapers, news wires, news magazines, television networks and radio. Below are several example Web sites.
3.1 Newspapers
Currently 800 newspapers are available on the Internet, eight times as many as two years ago. Many of these newspapers are available on the Web in their entirety at no cost. Some are only partially available and require a fee for full access. Unlike previous text-only versions of online newspapers, today's electronic versions contain images, audio, and video. In some cases audio and video are available on demand, negating the need to download the entire audio or video file before being able to hear or see the news story. Readers are able to contribute their thoughts and opinions on stories using electronic mail and to see other readers' comments online. News is continually updated, which appeals to readers of breaking stories, such as sports news or conflicts in progress.
Of the 800 newspapers online, 717 are accessible on the Internet, 44 are available on online services, and 39 operate Bulletin Board Systems (BBS). The BBS allows users to avoid the cost of getting Internet access from an Internet Service Provider (ISP). There are 450 newspapers online in the United States, 212 in Europe, 49 in Canada, 38 in Latin America, 38 in Asia, 10 in Australia and New Zealand, 7 in Africa, and 7 in the Middle East. Some examples of newspapers on the Internet include; USA Today, The New York Times, Wall Street Journal, The Washington Post, San Jose Mercury News, The Irish Times, and Le Monde (France).
Very few newspapers are making money from their Internet-based systems. One of the exceptions is The Nando Times from North Carolina, which has over 2,500 paid subscribers that access the news paper either on World Wide Web or with Nando Net's BBS. Nando has archives of news and uses photographs and advanced multimedia effects implemented with Java extensively.
3.2 Web TV
In the past, television was only distributed via cable, satellite or terrestrial systems. Today, with the increase in Internet connection speeds, advances in technology, the increase of total number of people online, and the decrease in connection costs, it has become increasingly common to find traditional television content accessible freely and legally over the Internet. In addition to this, new Internet-only television content has appeared which is not distributed
via cable, satellite or terrestrial systems. Internet TV can come in many forms. For instance, it can:
· be watched on a regular TV (via a Set-top box), or on a computer, or on a portable device (such as a mobile phone)
· show a channel 'live' (like regular TV), or allow the viewer to select a show to watch on demand ("Video-on-Demand")
· involve any budget - from home camcorder productions to expensive professional productions
· be protected from copying, or easily duplicated as a perfect copy
· be free or paid for - and may be supported by advertisements
· be an interactive or passive medium
One of the barriers to wider adoption of Internet television is streaming technology, which can be of poor quality and high cost to the providers. The BBC's Dirac project seeks to address this by creating a scalable, high quality,
free codec for streaming video content over the net. .
As Internet television becomes more pervasive, efforts are being made by companies such as JumpTV to develop the transmission of existing pay TV channels to regular TV sets over the net, while retaining control over how the media is used. Such control is required in order to protect existing subscription and pay-per-view business models. Major television networks also have descriptions of their television shows, transcripts of news broadcasts and timetables for their programs. Some major television networks on the Internet with news content include NBC, CBS and CBC. CBC has transcripts of The National, a nightly news program and CBS has a daily on-demand video of their Up to the Minute news broadcast.
3.3 Web Radio
Internet radio (aka e-Radio) is a broadcasting service transmitted via the Internet. Not every internet "radio station" has a corresponding traditional radio station. Many internet radio stations are completely independent from traditional ("terrestrial") radio stations and broadcast only on the Internet. Broadcasting on the Internet is usually referred to as webcasting since it is not trasmitted broadly through wireless means but is delivered over the World Wide Web. e-Radio suggests a streaming media that presents listeners with a continuous stream of audio to which they have no control much like traditional broadcast media. It is not synonymous with podcasting which involves downloading and therefore copyright issues. Nor does e-Radio suggest "on-demand" file servering. .
Because the radio signal is relayed over the Internet, it is possible to access the stations from anywhere in the world, for example, to listen to an Australian radio station from Europe or America. This makes it a popular service for expatriates and for people who have interests that may not be adequately catered for by their local radio stations (such as progressive rock, anime themed music, 24/7 stand up comedy, and others). Some of the internet radio services offer news, sports, talkback, and various genres of music, everything that is on the radio station being simulcast over the internet with a netcast stream.


3.4 Podcasting
Podcasting is a collection of technologies for automatically distributing multimedia files (audio, video etc) over the Internet using a publisher/ subscriber model. It differs from earlier online delivery of audio or video because it automatically transfers the digital media files to the user's computer for later use. Podcasting enables independent producers to create self-published, syndicated "shows," and gives broadcast radio or television programmes a new distribution method. Podcasts can be played via any digital audio player or computer with audio-playing software (pocket PCs, mp3 players, pda, PC, iPod). Since RSS was developed, feeds have been used to deliver not only audio, but video files and other media such as photographs and text by podcast. Podcasting's essence is about creating content for an audience that wants to listen when they want, where they want, and how they want.
Top Web Resources for podcasts:
· Podcasting News' Podcast Directory is a good place to start.
· iPodder.org is home of one of the first podcast applications.
· A Podcast Directory is available at Podcast.net.
· Podcast Central is a mini-portal of podcast info.
· Audio Weblogs has a list of the 100 Last Podcasts.
· Podcast Bunker is a search tool for podcasts.
· Trade Secrets Podcast.
· SportsPod has the right idea - sports broadcasts on demand.





4.0 The impact of Internet multimedia news on society
One of the major benefits of online news is the ability for users of the Internet to gain different perspectives on news. Users are no longer dependent on their traditional sources to receive their news, but can now reach news services around the world. The global accessibility and rapid availability of news may result in different opinions of events. Local biases in reporting may now be quickly offset with information from different sources at relatively low cost.
One of the most recent examples of bias in reporting deals with the diverse accounts for the number of people at the Montreal rally before the Quebec referendum in 1995. Internet news readers were not only able to get diverse views of this story from across Canada, but were also able to have continual updates of the referendum results, see reaction to the referendum from around the world, and gauge the reaction of financial markets.
In other cases, the 'Trial of Century', namely the O.J. Simpson case, was extensively reported and watched on television. Television has a linear format for presenting information. While television viewers had the option to change channels, most channels were reporting the same information in similar formats. The World Wide Web can provide users the freedom to choose the news stories that they want, to be presented in formats of their choice, and to see the news when they want. While this style of news delivery has many advantages to the consumer of news, it does represent a change and loss of editorial control for news providing organizations. To what extent will users be empowered to control the news they want to see and what effect this will have on society will probably be determined over the next few years.









5.0 Conclusion
Perhaps the most powerful aspect of computing technology is the ability to combine text, graphics, sounds, and moving images in meaningful ways. The future of online newspapers will bring about intelligent agents who will keep users informed of news by browsing on behalf of users. Current filtering systems are based on keywords, but future systems may use knowledge-based techniques to filter information more accurately than existing methods. Such agents will pose threats to user's privacy and security. Improvements in online interactive multimedia will increase the dramatic effects and impression of news and result in new forms of electronic advertising. The global expansion of online news services on Internet will also increase the amount of news available to users from what was previously available from traditional television news sources. What is largely unknown to the news industry is the extent to which users will be willing to pay for access to such services. Users have so far resisted fees, in part due to the large availability of free Internet news. Understanding effective design of online interactive multimedia and the needs of users will be key to future successful Internet-based news delivery systems.














REFERENCES

M. Dastbaz (2002). Designing Interactive Multimedia Systems. Published by McGraw-Hill by Steven Gardiner Ltd, New York, NY 10020. OUM Digital Library, Kuala Lumpur.

Nantha Kumar Subramaniam & Rohaizak Omar @ Abd. Rahim (September 2006). Interactive Media (CBMI4103). Published by UNITEM Sdn Bhd, Kuala Lumpur, Malaysia. OUM Module.

http://streamingmedia.stanford.edu

http://www.streamingmediaworld.com

http://www.isoc.org/inet96/proceedings/a7/a7_1.htm

http://encyclopedia.thefreedictionary.com

http://www.cs.su.oz.au/bob/land.html

http://www.ukoln.ac.uk/qa-focus/documents/benefits/breifing