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Real Video, Part 2
technofile  by al fasoldt
Columns and commentaries in a life-long dance with technology 
Simple gray rule

Making your own RealVideo files

Technofile for April 20, 1997

By Al Fasoldt

Copyright © 1997, Al Fasoldt
Copyright © 1997, The Syracuse Newspapers

Last week I described an amazing way to watch live TV programs on the Internet. The invention is called RealVideo. All you need to watch live or rebroadcast TV shows is a free software program from Progressive Networks, the developer of the RealAudio system.

The free RealVideo player (and a $30 version with more features) can be downloaded from the Progressive Network's World Wide Web site,

RealVideo turns normal TV pictures into highly compressed images that are reconstructed by the RealPlayer at your PC or Mac.

But the RealVideo folks have another treat. If you have any computer video files especially if you have a QuickCam camera or similar computer-based video device you can make your own RealVideo recordings. Think of them as the computer version of videotapes. And you can make your own live video for broadcast on the Web.

The RealVideo encoder is a software program available only for Windows 95 and its heavy-duty cousin, Windows NT. It's free, although the current version will stop working in June. (Progressive Networks will have an improved version before then, but it may not be free.)

You can download the free RealVideo encoder from this Web site: You may find the site busy at prime time; if so, try it before dinner or when you first get up in the morning.

I've been making my own RealVideo TV Webcasts for a few weeks. Although I appear on a regular TV show, I'm still too shy to send out my live TV signals to anyone outside my home-office network. But I've also converted many of my standard Windows video recordings called AVI files to RealVideo recordings, and I've done the same thing for the half-dozen home-grown AVI recordings I made of the neighbor kids when they were clowning in front of the camera.

In all cases, the resulting broadcasts and recordings were better than I had expected. The live camera feeds could have used more processing muscle a computer faster than my 100 MHz PC would have helped because the work of squeezing the data in each picture must be done instantly, in real time. But converting my AVI recordings into RealVideo files went very well, because processor speed does not matter. (Slower computers just take longer to convert the videos.)

Two aspects of the RealVideo encoder impressed me when I converted my AVI files.

First, the encoder provided many quality levels. I was able to choose the appropriate level easily. (Choices include a "talking heads" option for videos that don't have much movement, for example. This keeps you from wasting a lot of the video on scenes that are static.)

Second, the resulting RealVideo files took up only a small fraction of the file-storage space the originals did. This showed how clever the RealVideo encoding technique is, because I was careful to make sure the videos retained as much of their original quality as possible. (The encoder has two main viewing windows, so you can look at the original and the encoded RealVideo version at the same time, while you are creating the RealVideo file. This makes it easy to see if the RealVideo version is faithful.)

One of the AVI videos of the kids next door is stored as a 13-megabyte file and plays for about three minutes. The RealVideo version is less than 1 megabyte. The original would not fit on a floppy disk and is too big to send across the Internet to a typical user with a dialup connection, but the RealVideo version fits on a floppy with room to spare and can be sent by e-mail easily.

The sound quality usually suffered on all my RealVideo productions, although it was usually good enough for kids-making-faces recordings. It was never up to real hi-fi standards, reaching the quality of good AM radio (in stereo) most of the time.

A quick note: You don't need to make your own computer videos using a QuickCam camera or any other video device to try out the RealVideo encoder. Everyone who has a Windows 95 installation CD has AVI files available. There are some excellent ones on the CD-ROM.

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