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About Streaming ServicesThis section provides documentation and support for streaming media usage at UIC, sample applications of streaming media, content creation tips, detailed usage instructions for our Flash Streaming Media Server and the tools you need to use, and a variety of related third-party links. You can contact the ACCC Streaming media administrators at the special email-address streaming@uic.edu What is streaming?Most files on the web have to be downloaded entirely before you can open/view them. For multimedia files, this can take extremely long. Thus those files are preferably streamed, i.e. they are sent in a special format, allowing the player application to view the file almost right away, before receiving the entire file. An audio clip can thus begin playing after just a few seconds of buffering (=downloading part of the file into memory). The buffer holds just a small part of the file, and while you are listening (or watching video), the next parts are being downloaded. Obviously, if your connection is not reliable, you may use up this buffered data before a sufficient new amount has been downloaded. This phenomenon is called Net congestion and may interrupt your playback briefly while new data is buffered. For a good user experience, it is thus crucial that your media be designed with the target audience in mind, balancing quality with the available bandwidth. Why stream and when?Streaming is useful whenever users want to open a large media file without waiting. While applications or packages typically have to be downloaded in their entirety before you can do anything with them, there is no reason why you should not be able to see the first minute of video while the next minute comes in. On the other hand, there is no need to use streaming methods if your data are stored locally, on your PC. While the media files can in fact be played back from, say, a CD-Rom, they will not really be streamed. Thus you will not have any buffering-induced delay in playback. Have you ever waited impatiently for a webpage to fully display, so you could interact with it? Waited for one image after the other to slowly appear? Well, the http://-protocol used for the web is not a streaming protocol. There is no special intelligence in it that would preload the next page you want to view while you are reading the current one (although there are some add-on programs that do just that). What is needed?See the pages on media creation for details, but basically you need:
For video capture, you would additionally need:
Alternatively, a digital video camera and IEEE-1394 (Firewire) adapter can be used, or a webcam for speaker video. You may then need additional software for format conversion. Who does the work?Most of the time, you and your staff will have to do this yourself. The Instructional Technology Lab staff will be happy to show you the basics, give you producion tips, and guide you in the creation process. However, we cannot shoot your video, convert the clips for you, or create your SMIL presentations. There are commercial production houses for this kind of work, at UIC the Center for Advancement in Distance Education (CADE) provides production services. Whoa! I need help!Questions about streaming media? Send them to itl@uic.edu or request an appointment in the ITL . Questions about the ACCC RealServer or the files you placed there? Contact the ACCC Flash Media Server administrator at streaming@uic.edu Streaming FormatsThe current leader in the market is Adobe Flash video. Popularized by YouTube, it has given people the ability to view video with out the need to install an external application to view video. The original developer and once market leader, RealNetworks, pioneered streaming audio and video, and version 4 of their player was the first streaming video playback tool. RealVideo uses advanced encoding mechanisms to convert the enormous digital video files to a manageable size, but many quality tradeoffs are to be made. Since version 6 (G2), SMIL multimedia presentations are possible. RealPlayer (now in version 11) is available for Windows, Mac, and various Unix environments. File formats: .rm (Realmedia=audio, video), .ra (Realaudio, older), .smi (SMIL multimedia presentations), .rp (Realpix, pictures with effects), .rt (Realtext), .swf (Macromedia's Shockwave Flash), .jpeg, .gif, .png (images), etc.; current player version: 11. The second player in the market is Microsoft with Windows Media Technologies. Their Windows Media Player is now also widespread, but this is a Windows-only solution. File formats: .asf (Asynchronous Streaming Format), .wma (Windows Media Audio); current player version: 11 on Windows XP and Windows Vista. Apple's Quicktime finally made the step to streaming in the summer of 1999. Long the leader in video-for-download, Quicktime is a mature platform with exceptional quality. File format: .mov (Movie); current player version: 7. |