If adding streaming audio to a web site is a black art, what about video? Moving images are really the final step in the evolution of the web. Streaming video completes the loop, giving a communication tool that offers all the advantages of video tape without the problems of distributing hundreds of cassettes.
So why has video taken so long to catch on? The answer is simple - bandwidth. Reasonable quality video in an eight-centimetre window needs broadband speeds if it is to work. In reality this means between 200-400kbps (kilo bits per second).
That’s 25-50 kilobytes of information for every second you wish to stream, or 1.5 - 3Mbytes for every minute. As you can see, the file sizes get very big very quickly. My evaluations have shown that a stream rate of about 225kbps is required for reasonable, watchable video in a small-ish window. That’s five times faster that a dial-up modem can deliver and about half the speed of a typical broadband or office LAN (Local Area Network).
In comparison, you can stream reasonable quality audio at around 32kbps - low enough for even dial-up modems. In reality, things are not so simple. The trick with streaming video and audio is to pick a streaming rate that is SLOWER than your typical connection speed. That way, the end user’s PC buffers the incoming signal so that you have something “in reserve” if the connection falters a little.
If the connection doesn’t play ball you run the risk of a buffer overrun, which leads to that annoying stuttering and freezing that you so often see on the net.
But before you all rush out to put the latest corporate video on your intranet I suggest you speak to your techies first. While most corporate intranets are more than capable of streaming a file at 200-300kbps we have overlooked one problem.
What happens if 5,000 people all want to view it at once? Can your server handle that many people? Can the infrastructure cope with that much data? Will you stop other people from carrying on their essential work if you take up that much bandwidth?
Assuming that your office network is robust enough to cope what exactly can you stream and how? You can take any MPEG, WMV or Quicktime movie and stream it over the web. You can even convert DVD material into a suitable format and stream that too, although the level of complexity goes up accordingly.
DVDs are actually very clever devices made up of a host of different computer files. The trick if you wish to stream them is to extract the video and audio files from the DVD using a process called ripping.
Once extracted you can then convert the resultant .VOB files to smaller, faster MPEG or WMV files. Unfortunately, there are a lot of industry standards out there and one-size fits all approach is virtually doomed to failure.
PCs running MS Windows are generally happy receiving Window Media Files (.WMV), whereas Macintosh users are going to be happier with Quicktime movies. But if you host all your videos as Quicktime, the chances are that Window users won’t be able to view them. MPEG files are great, but again, older versions of Windows Media Player won’t like them.
A solution is to offer users a choice of file formats on the same page and let your users choose. Or, given that Macintosh users are in the minority anyway, just ignore them and settle for .WMV - I know it’s harsh, but if they are really keen they will download and install the Windows Media Player anyway.
Another solution involves using Macromedia Flash, the plug-in for which can be found on more than 90-95% of all machines in the world apparently. Flash is truly cross-platform, but your end user must have the plug-in Installed otherwise all they will see is a blank box.
The other advantage of using Flash is that you can build the video player right into the page, complete with stop, play, pause and rewind buttons.
Learning to stream video takes time. Get the stream rate wrong and your videos will stutter like Norman Collier. Get the CODEC wrong and half your users will hear the audio, but not see the video. Rip your DVD incorrectly and you will have video and audio that don’t actually synch up.
Frequently Asked Questions
Q. What is streaming video? A. It is video delivered to your computer that can be watched while it is still downloading.
Q. What do viewers need to have on their computer? A. A soundcard and speaker(s) or headphones, their normal browser software and a so-called plug-in - a small piece of software that converts the data into sound. If you opt for .WMV streaming they will also need the Windows Media Player.
Q. This all sounds expensive - is it? A. Not really. The programs needed to convert video into a streaming format are very reasonable. I recommend MSIVideo (http://hop.clickbank.net/?snichols/msincome) Its great, very easy to use and only costs $39.95. Another alternative is Webmaster media maker (http://www.webmastermediamaker.com/?hop=snichols)
Q. What is the quality like? A. Judge for yourself - visit http://www.infotechcomms.co.uk/info10.htm and watch the demonstration programme. The trick is to get the quality as high as you can, but still make it playable on an average modem-equipped home computer.
About the Author
Steve Nichols is a freelance journalist who runs InfoTech Communications (http://www.infotechcomms.co.uk). A background in radio means that Steve was ideally placed to take advantage of the arrival of streaming media via the web.
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What a wonderful article !
Tina.