LIVE STREAMING VIDEO
Made Somewhat Less Complex!

...just be thankful if it works at all

Why is live streaming video a bit like an old episode of "I Love Lucy?" Do you remember the episode where Lucy and Ethel worked in a candy factory? All Lucy had to do was pick up the candies off the conveyor belt and put them neatly in boxes...but the belt was sometimes fast and sometimes slow.

This is pretty much the way the internet works. Data flows across the net much like little candies on a conveyor belt. Sometimes the belt (net) runs fast and sometimes it might be painfully slow.

So what does this have to do with live streaming video?

Most of us know that video is a series of still pictures that, when viewed one after another, create the impression of movement...remember those old flipbooks. Internet, or live streaming video, works like that...sort of. Because of the tremendous resources (bandwidth) necessary to transmit video through your cable or through the air, a less "intensive" method needed to be developed for the internet.

Internet video is "compressed" meaning that only the parts of a picture that change from frame to frame are sent to your computer. For instance, a person talking in front of a white wall is easier to send because much of the picture remains the same from frame to frame. However a shot of children running and playing might be harder to send because so much of the picture changes in each frame.

That's why a video of someone talking seems to move naturally while a shot of a baseball game might appear to be a series of jerky still shots.

REALVIDEO is a scheme that looks like the your television. It transmits picture and sound in highly compressed data packets (remember those candies) over the web to you. Realvideo requires a special "plug-in" that must be installed on your computer.

How Slow is Slowwww?



You will get an idea of just how much the internet "belt" slows down and speeds up by looking at the "statistics" function on your Realplayer (under the "view" menu) while you're looking at a web video. It's a bit horrifying to note that on many connections you actually receive no information for seconds on end. To overcome the uncertain data rates of the web, the folks who created the Realplayer wrote in a "buffering" scheme.

Have you noticed that your video doesn't start right away when you connect using your videoplayer? Your player is "buffering" or storing data in the computer memory to make up for times when the web slows down. When the web really slows down, no amount of buffering will help and the picture will freeze. You will get the dreaded message of "net congestion."

One of the great things about REALVIDEO is that you can broadcast sound. It's one thing for your picture to jerk and stop but it would really be unsettling for the sound keep slowing down. For that reason we've configured our broadcast to favor sound in the event of a web slow down. Even if your connection is slow and your picture stops, you should still be able to hear steady sound.

HOW ABOUT SOME USEFUL TIPS
Okay, here they are....

Download the FREE Realvideo Player. They don't make it easy, they want you to buy the flashy player, but don't do it. It does nothing useful for you

Minimize the size of the Realplayer on your desktop. It will always float on top but get rid of those "channels" by clicking on the size icon.

You may increase the size of the image by dragging the program box and making it larger. The bigger picture is the same "resolution" as the smaller picture so it won't look any sharper but it might be easier for the class to see. You can enlarge to full screen if you have a fast video card in the computer and a good connection.

Please only use one computer in your lab for receiving REALVIDEO. Two reasons...we pay by the computer connection so help us save money, also since data reaches each computer at different times you will hear a cacophony of sound that will drive you nuts.

TECH NOTES for video streams

We're using two streaming servers for this webcast. One is especially for schools with fast connections and the other is for schools with slower connections.

Of the two streams we're using the broadband stream should be sharper. It should show as 320x240 pixels. If you have a high quality connection you should get 150kbs. Look at the lower left corner of theRealplayer and it will tell you in kbs (kilobits per second) your connection speed (the speed at which the Realserver is able to send your video). If you have a high speed network this stream should read 150 to 100 kbs.

The slower connection is set for 28.8 and 56k for DIAL-UP accounts.

If you are on the broadband stream and it is reading 20kbs then either your connection is SLOW or your realplayer is not set to match your school's connections.

The faster your connection the better the picture should be. If you have a fast connection but you're getting a slow kbs rate (remember to check the lower left corner of the Realplayer) then double check that Realplayer is set for your connection speed.

Try both streams and see which one looks best for you. You may also want to try some other streaming sites and compare the quality of the image to what we're sending. We'll do our best to send you the best quality video the internet can handle.

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