Create Media for Online Delivery
Overview
The two main forms of video delivered over the internet are streaming and progressive download. The Helix server deals only with streaming media. Streaming media is served by a specialized server. The media never really resides on your computer, it is played through your browser via a plug-in, or smaller application which provides your computer with extra features. For example, the Real and QuickTime Players are plug-ins which allow you to open media files. Many computers already have a player installed; if yours does not, free downloads are available through the links under Browser Setup below.
There are certain cases when progressive download is preferable to streaming. If you need to play something over and over quickly or jump from place to place in a video, then progressive download is a better choice. The first time a progressive download file plays, it gets saved to your hard drive. Once it has played, it can be managed in much the same way as a VCR. You can cue forward and reverse or jump to any spot with no buffering delay. The word "progressive," in this case, refers to the fact that the media plays the first time as it is downloading. Many people mistake this behavior for true streaming. Progressive download is generally not a good solution for lengthy video programs due to the amount of disk space required on the computer receiving the file.
Copyright Issues
Please be aware that any video files that are uploaded to a site must comply with the Teach Act. To ensure that you do not infringe upon copyright law please read the above link to "copyright issues." You may use the following link as a guideline also,copyright guidelines.
Recommended Formats
For web streaming, we recommend creating QuickTime and Real Media files.
MP3 and MPEG-4 files are not recommended at this time, because of technical difficulties associated with streaming them on the Helix server. MP3 files are recommended for use in Blackboard Vista, and can be uploaded directly onto Blackboard Vista sites. For further information, or assistance with using MP3 and MPEG-4 files in another setting, please contact Instructional Design and eTeaching Services eteach@bc.edu.
Recommended Compression Tools
If you are able to digitize your own media, the following table contains guidelines for free or inexpensive compression tools, suggested formats, bandwidth and syntax examples.
Macintosh
- Helix Producer Basic to create Real Media files
- IMovie (May already be installed with Mac OSX)
- QuickTime Pro for Mac $29.95
Windows
- Helix Producer Basic to create Real Media files
- MovieMaker (May already be installed on with WinXP)
- QuickTime Pro for Win $29.95
Recommended Compression Settings
Creating QuickTime Files
The following table illustrates settings used to create QuickTime files using programs such as QuickTime Player Pro, Helix Producer Basic, iMovie, and Cleaner (we recommend using the same settings if you are using other compression tools).
| Options/Settings | 56 K | DSL | Broadband |
| Compression | Sorenson3 | Sorenson3 | Sorenson3 |
| Quality | Best | Best | Best |
| Motion | 12 frames/sec 10 for key frame/sec |
24 frames/sec 10 for key frame/sec |
30frames/sec 10 for key frame/sec |
| Data Rate |
30kbytes/sec | 100kbytes/sec | 150kbytes/sec |
| Sound (voice only) |
Qualcomm Pure Voice, 24,100khz, 16 bit and mono, full rate |
Qualcomm Pure Voice, 32,100khz, 16 bit and mono, full rate |
Qualcomm Pure Voice, 44,100khz, 16 bit and mono, full rate |
| Internet streaming/hinted streaming |
select | select | select |
| Size- width/height |
160x120 or 120x90 |
320x240 or 400x300 |
320x240 or 400x300 |
Note: We are currently recommending Sorenson3 but this may change in the future.
For further information or assistance, please contact Instructional Design and eTeaching Services eteach@bc.edu.
Creating Real Media Files Using Real Producer 10
We recommend creating a SureStream file for 56K, 256k, and 384k.
1. To do this, click on "Audiences." A New window will open.
2. Select "56K Dial-up," and then click on arrow button.
3. Select "256K DSL or Cable," and then click on arrow button.
4. Select "384K DSL or Cable," and then click on arrow button.
5. Close the window.
For more documentation, please view Using Real Producer 10
Ways to Link Media Files
QuickTime
- To open with the player:
Example: rtsp://gulf.bc.edu/webct/hac/wow.mov
- To embed in a web page:<embed src="wow.mov" width="320" height="256" autostart="false"></embed>
Note: This file must first be processed with a tool called MakeRefMovieX. You can get it here.
Read Media
-
To open with the player:Syntax: http://gulf.bc.edu/ramgen/webct/hac/wow.rm
- To embed in a web page:
Syntax: <embed src= "http://gulf.bc.edu/ramgen/webct/hac/wow.rm" type="audio/x-pn-realaudio-plugin" controls="ImageWindow,ControlPanel" width=320 height=240 autostart="false"></embed>
Resources
- Real Network Tutorials
- Real Network Documentation for Content Authoring and Production
- QuickTime Tutorials
Know Your Audience and Their Limitations
Since your users may have different platforms and have a range of connection speeds, you should offer choices to accommodate both PC and Mac users with 56K, DSL, and Broadband connection speeds.
For assistance, please contact eteach@bc.edu.