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Wednesday, February 15, 2006

How To Add Streaming Video To Your Web Site


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.

Video Conferencing: Choosing A Camera That Is Best For You

When you think of video conferencing you probably picture a webcam perched on a computer or monitor recording your image and sending it out to the world. While webcams are most frequently used by online conference participants, it is also possible to get the work done with a digital video camera. Which webcam or digital video camera you opt for depends on your needs. Here are some points to consider when making your selection.

Webcams

Nowadays, web cams can be found for under $20 and go all the way up to $150. The difference between the high end cameras and the starter web cams are usually due to the quality of image that is put out.

First, take a look at the resolution of the camera. Ideally you should get a webcam that can produce at least a 640x480 resolution.

Then check how many frames per second the camera can handle. For video conferencing the ideal level is 30 frames per second (fps).

Finally, find out what kind of sensor the camera uses. The better web cams use CCD technology instead of CMOS. Also, remember that most webcams connect to computers with a USB cable.

Digital Video Cameras

For an even better result (sharper and faster images), you can use digital video cameras. These are the same devices that are used to record home movies, etc. Digital video cameras start as low as $250 and go up to thousands of dollars. In order to use a digital video camera, you need to make sure that the device supports a USB or a Firewire output and that it can be used as a webcam and connect you with online applications.

Whether you use a webcam or a digital video camera depends on the type of conferencing that you will be doing.

If you’re meeting in a manner in which the quality of the video is not too important, then a lower end webcam will probably suffice. However, if you need quality video, then a higher end webcam, or even a digital video camera will be required.

If you’ll be in a conference room setting, in which you need to get more than one person on camera, a digital video camera with tilt/pan/zoom capabilities will work best.

Firewire digital video cameras provide images that are so nice that you can see the second hand of a watch sweep by. You can also see details of products and items that normal webcams simply cannot provide. This is because firewire handles the processing of video much better than USB does, allowing for smoother images and better quality.

When you are out shopping for webcams, take a look at Logitech products. They are one of the leaders in this field and have a wide variety of models. They offer great products at reasonable prices. For digital video cameras, Canon offers a good selection and devices of excellent quality.

So, consider your needs and your budget and then find a webcam or a digital video camera that is best for you.