The Test
Because I only have access to Sorenson Video 3 Standard, the only compression option available is the Basic compression option. I previously have been using the Sorenson Video 2 Professional Edition, and the two have very different variables, which can be set in Cleaner 5. To try and make the tests come out as close to one another as possible, I used the secret DMN TV compression settings that were used in the latest edition of DMN TV (www.dmntv.com), which happens to be compressed at 15 FPS at 240 x 180.

I also want to make it clear that these tests are being done with the Standard version of Sorenson Video 3. Results should be quite a bit different when using the Professional Edition.

I compressed these files three times; Sorenson Video 3 Basic, Sorenson Video 2 Professional Edition with Basic settings and Sorenson Video 2 in VBR.

The first round of tests were done at 300 kbps which is a speed designed for viewers on a DSL or Cable modem. At this rate, all of the video looks pretty good, with only slight variations in the canyon and clouds example. The biggest differences can be seen in the fire example. As far as over all quality goes, Sorenson Video 2 Basic comes out on top in this example. While it is slightly "fuzzier" than the other two, it maintains the frame rate and contrast over the others. Sorenson Video 2 VBR doesn't really come out well in this series, and while Sorenson Video 3 Basic maintains the best detail; for some reason the compression falls apart in the last moments of the video. (I reran the compression several times with the same results.) I should also point out that no keyframes were set in these examples, which would have improved the quality of each of these clips.

The big difference that can be seen in these examples is in file size:

300 kbs file size results
Canyon
Sorenson Video 2 Basic 902KB
Sorenson Video 2 VBR 871KB
Sorenson Video 3 Basic 866KB

Clouds
Sorenson Video 2 Basic 536KB
Sorenson Video 2 VBR 513KB
Sorenson Video 3 Basic 498KB

Fire
Sorenson Video 2 Basic 472KB
Sorenson Video 2 VBR 373KB
Sorenson Video 3 Basic 566KB

Because of the fast motion, contrast and other aspects of the fire video, Sorenson Video 3 Basic does fall behind the Professional settings of Sorenson Video 2. However, Sorenson Video 3 Basic does beat the other two in the other examples. While this may not seem like big differences, remember these are short video clips. Over the long run the file size savings will add up.

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