Recently Sorenson released the Sorenson Video 3 CODEC. According to Sorenson, this CODEC is a vast improvement over Sorenson Video 2, giving higher quality video at the same bit rate with faster compression and making better use of VBR (variable bit rate). Currently, Sorenson Video 3 is available in two forms; Sorenson Video 3 Standard Edition, which is included in the latest release of QuickTime 5.0.2, and Sorenson Video 3 Professional Edition.

The Professional Edition has many more features over the Standard Edition, including:
· Improved performance
· Enhanced quality
· Support for alpha channel/chroma key
· Color watermarks
· Automatic keyframes through scene change detection
· Bi-directional prediction
· Support for two-pass Variable Bit Rate (VBR) compression
· Block refresh for packet loss correction
· Media key support through secure encryption
· Compression time packetization for error resiliency to packet loss

Of course reading about Sorenson Video 3 gives you one impression. How does the new CODEC actually work?

I haven't received the Sorenson Video 3 Professional Edition as of this writing, but I was eager to check out the compression quality available in the Standard Edition. If you follow DMN TV, our streaming media show, which is part of the Digital Media Net family, you may have noticed our latest edition is encoded with Sorenson Video 3. Co-Producer Paulo de Andrade and I were both amazed at the quality we were able to achieve with this new CODEC and have decided to encode future editions of DMN TV in this same format.

But how much better is SV3?

I took some time this week to encode some footage supplied by our friends at Art Beats from their Digital Film Library to find out. I selected three clips for this test, each for their unique qualities that can make compression and streaming difficult.

From the Reel Fire 2 collection, I used the brushfire ignition clip (RF202). This clip offers many hurdles for encoding, including fast motion, detail and huge areas of contrast, all of which which can make video compression a nightmare.

Because not everyone needs to compress video that has these specifications, I compressed a cloud fly through from the Cloud Fly-Thrus 2 collection (CF217). While this video clip does have some drastic motion, that is typical in many streams today, it also has subtle color and tonal variations that can be lost when a video is compressed for the Web.

For the final clip of this test, I wanted something that combined both of these, so I chose a canyon fly over from the Aerial Landscapes collection (AL110A).

Incidentally, if you would like to view each of these in their pre-Digital WebCast forms, visit www.artbeats.com and use the reference numbers above to access the clips.

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