Real Video

Video over the Internet for most users is a curiosity. At normal modem dial-up bandwidths, such as 28.8kbps or 56kbps, it is one step up from unwatchable. However, this curiosity is full of promise. Streaming video, such as Real Video, will be the technology that transforms the Internet from a bastard offspring of print into a full entertainment and information medium combining all the strengths of past media with interactivity. Currently broadband in the form of cable modems and ADSL reaches about 1.25 million users (1 million cable, 250K ADSL). If you think Real Video is a powerful technology now, then wait a few years until broadband truly penetrates the consumer market. Then you'll be glad you learned about Real Video back when it was new.

Broadband has a lot of promise. For those of you with fast connections try a couple of the high-bandwidth aggregation sites, onBroadband.com and Broadband Zone.com. The first has links to Broadband content; the second has info on broadband and interactive TV tools as well as a great content library. For those of you with slower connections let's talk about how to develop video that works well on slower connections that form the mainstream today.

Shooting the Video

If you are creating the video yourself there are ways you can shoot the video that will make it easier to encode to Real Video. Always make sure you tape to the best source tape possible. The best in descending quality are:

  1. Beta Cam SP - Used by professionals for TV
  2. Digital Video or DV - Video captured as digital video and dumped to a hard drive
  3. S-VHS or 8mm - Two common formats in higher end home camcorders
  4. VHS - The classic format, tends to have a lot of noise that makes it harder to encode, but sometimes that's all you have.

When shooting use a camera on a tripod. Lot's of movement makes for a hard to encode picture. Lot's of camera pans, wipes and transitions are also hard to encode. Talking head shots are the easiest to encode, but they are also boring, so mix it up a little. After a movement, leave a second or two for the scene to "resolve" before having anything important happen.

Digitizing the Video

Since we are encoding to Real Video, which will be running at a low frame rate we don't need to capture video at full screen and 30 frames per second (fps). To save hard disk space and make encoding easier, we can capture at 24bit color, 15 fps, and 320x240 pixels. Always make sure to capture uncompressed video so that you have the best possible source file to work with.

Video captures should be done on a fast machine since the CPU often does most of the encoding. Make sure you have at least a fast EIDE hard drive or a SCSI drive. The video capture card doesn't need to be a top of the line card. The Intel Smart Recorder III is a good card selling for $199 that offloads a lot of the processing on the CPU making it cheaper. Adobe Premiere is good capture software or you can capture directly in Real Producer.

Encoding to Real Video

Real Producer is the free version of the encoding software from Real. It is best for single bandwidth encoding. If you would like to take advantage of SureStream, that allows you to encode a number of different bandwidth streams into one file, then try Real Producer Plus or Real Producer Pro. The Pro version has a number of SMIL templates that make it easier to publish SMIL files.

Go ahead and open the uncompressed video file that you digitized. When you first start Real Producer it will walk you through a Wizard. Choose "Record from File". Next you can choose to encode to a single stream or to SureStream with multiple bandwidths. Choose "Single Rate" for this example. You'll then be asked what bandwidth you’d like. Remember that 28.8kbps is almost unwatchable. 56kbps encoding is better, but will probably spend a lot of time buffering. Make the decision based on your target audience. Next you'll be asked to make a decision about the audio. Is it voice, music or a mix? After that comes a decision on video. Normal Video should be selected for video with mixed talking heads and motion. Smooth should be chosen for talking head shots, while Sharpest should be chosen for motion shots. Slide Show can be chosen for video that is basically a slide show with lots of still non-moving images. After that select a name return to the main screen and press "Start".

Embedding in SMIL

In our first article, The SMIL Primer, we discussed how to embed the Real Video into a SMIL presentation. Here is the code again.

<SMIL>
<HEAD>
<META NAME="title" CONTENT="WebReview Demo"/>
<META NAME="author" CONTENT="jrule@ruleweb.com"/>
<META NAME="copyright" CONTENT="©1999"/>
<LAYOUT TYPE="text/smil-basic-layout">
    <REGION ID="PixChannel" TITLE="PixChannel" LEFT="0"
    TOP="0" HEIGHT="120" WIDTH="160" BACKGROUND-COLOR="#888888"
    FIT="fill"/>

    <REGION ID="VideoChannel" TITLE="VideoChannel" LEFT="160"
    TOP="0" HEIGHT="120" WIDTH="160" BACKGROUND-COLOR="#888888"
    FIT="fill"/>

    <REGION ID="TextChannel" TITLE="TextChannel" LEFT="0"
    TOP="120" HEIGHT="50" WIDTH="320" BACKGROUND-COLOR="#888888"
    FIT="hidden"/>
</LAYOUT>
</HEAD>
<BODY>
<PAR TITLE="multiplexor">
    <VIDEO SRC="webreview.rm" ID="Video" REGION="VideoChannel"
    TITLE="Video"/>

    <IMG SRC="webreview.rp" ID="Headline Pix" REGION="PixChannel"
    TITLE="Headline Pix"/>

    <TEXT SRC="webreview.rt" ID="Ticker" REGION="TextChannel"
    TITLE="Ticker"/>
</PAR>
</BODY>
</SMIL>

 

Conclusion

Video delivery over the Internet continues to amaze me. I can remember back in 1993 trying to do Quicktime video playback from a 1X CD-ROM and finding it nearly impossible. A 1X CD-ROM is 100K/sec or 800kbps. That's half a T1 line! With that kind of bandwidth now we can do full motion playback at 320x240 using Real Video. The compression co-decs from Real have simply gotten that much better. As bandwidth increases and compression gets better expects streaming video to start competing with TV. Then the Internet will be a true mainstream entertainment medium.