This section gets really technical and requires an understanding of the codecs that come with QuickTime. If you're a beginner, it may not be for you and you might want to skip ahead.

Streaming Settings

You can compress for the web using QuickTime Player. Unfortunately, you need to upgrade to QuickTime Pro first.

If you buy any editing or compression software, it will probably come with QuickTime Pro. Otherwise, you'll need to register online for QuickTime Pro if you want to do anything other than watch.

To prepare a movie for HTTP streaming (progressive download), select File --> Export --> Options. Choose your codec then click on "Prepare for Internet Streaming" and "Fast Start - Compress Movie Header".

To ready a movie for RTSP streaming, open your already-compressed movie, then go to File --> Export --> and select "Movie to Hinted Movie" from the pulldown menu. Be sure to check "Make Movie Self Contained".

You can also buy additional software for really fine tuning your video streaming. Here's some now:

Sorenson Pro and Media Cleaner Pro

The professional edition of Sorenson 2 offers several new menus to accommodate HTTP and RTSP streaming.

Under the Encode Tab, "Automatic Keyframes" lets you add additional keyframes at set intervals, and the "Data Rate Tracking" option allows for "tight" or "relaxed" data rates. The more relaxed, the more the data rate can fluctuate depending on the content, which is better for HTTP streaming. A tighter the data rate means a more constant flow of information, which is better for RTSP streaming.

Under the Streaming Tab, the "Keyframe Size" option allows for "minimum" and "natural" sizing. Higher quality keyframes provide higher quality starting points for all subsequent interframes. For low-bandwidth RTSP streaming, keep this setting as close to minimum as possible. This will avoid unnecessary and erratic fluctuations which might throw off your steady stream of video transmission. For broadband delivery, keyframes can vary more in size according to the nature of the video content.

During RTSP streaming, some data may not make it all the way. "Force Block Refresh" updates any picture information which hasn't been updated during a specified time period. This helps restore clarity to garbled images without forcing the viewer to wait for another keyframe.

The makers of the Sorenson Pro suggest one compression technique that uses fewer keyframes but more detailed interframes. By cleaning up regions of the picture suffering from lost data without adding any keyframes you're less likely to throw off a steady RTSP flow of video. This trick seems particularly good for live streaming, where the speed and consistency of compression are more important than the image quality. To try it out, shut off automatic keyframes (set to 999999 or as infrequently as possible), and turn on a very short Force Block Refresh interval (set anywhere from 2-5 seconds).

Media Cleaner Pro further enhances the functionality of Sorenson Video (versions 1 and 2) with its "variable bit rate" (VBR) feature. Media Cleaner passes over your video twice, first, analyzing it, then, compressing it. This way, Media Cleaner can determine exacting keyframe placements and the best data rates for your video. VBR guarantees higher quality output for HTTP streaming. You can set a peak data rate if you want to keep your file size within certain boundaries, and, as always, the higher the data rate, the higher the quality (and the bigger the file size and, consequently, the slower the download).

If used incorrectly, VBR can be detrimental to RTSP delivery, because real-time streaming requires a steady flow of information. At high settings, VBR has too many fluctuations. Keep the peaks low and close to the average data rate.

For RTSP streaming, "Spike Suppression" is an alternative to VBR which prevents data rates from exceeding a specific "spike" level. It's faster but not as refined as VBR.

Until you have mastered the nuances of compression, experiment with different codec settings on short clip excerpts that best reflect your overall movie.

For more info, download the Media Cleaner Pro instructions from the company web site.

QDesign Music Pro

One complaint with QDesign Music is that the audio sounds "hollow" or "tinny" - this can be remedied by upgrading to QDesign Music Pro, which offers much more range in its compression, and some would say it's on par with, or better than MP3.

To prepare real-time streaming audio, choose a bit rate that's slightly less than that of your audience's connection speed. For example, if you want to compress music for a 28.8 bps modem, save at 20 - 24 kilobits per second.

Presets

Media Cleaner Pro also includes excellent presets for QuickTime, MP3, Real G2, and Windows Media (ASF) formats.