BitJazz make some fairly serious claims for their SheerVideo codec, but fortunately, these claims are easy to test. They claim it will "save both time and space in professional video and film production and archival, yet always maintains absolutely perfect fidelity." I have traditionally used the Apple "Animation" codec at 100% quality and "Millions of Colors+" to create "uncompressed" video, usually from 3D animation tiff sequences, in a production workflow to maintain absolute picture quality and the essential alpha channel for compositing work. It is in this environment that I decided to compare SheerVideo to "Animation 100%". In comparing the two lossless codecs, I also decided to try some lossy codecs to see what difference they made in terms of picture quality, file size, and playability. I have often used "photoJPEG" codec at 100% quality in compressing 3D animation files for real-time playback on slower machines or for smaller file sizes, and I was curious to see how Apple's new Pixlet codec would also perform in this environment.

The speed and file size testing consisted of compressing a 200 frame tiff image sequence. The resolution of the tiffs was 960 x 540. I used an 800mHz 17" LCD iMac for the tests, compressing from and to the internal hard drive.

Lossless Codecs
200 frame 1/2 HD (960 x 540) movie, to SheerVideo 56 seconds, 121MB
200 frame 1/2 HD (960 x 540) movie, to Animation+ 67 seconds, 223MB

Lossy Codecs (for comparison)
200 frame 1/2 HD (960 x 540) movie, to Pixlet 91 seconds, 39MB
200 frame 1/2 HD (960 x 540) movie, to Photo-JPEG 46 seconds, 31MB

It's pretty obvious from the figures that both of BitJazz's claims about their SheerVideo codec are backed up by these results. It was the second fastest codec in the test, knocking 11 seconds off the time to go out to Animation+, and produced a file just over half the size.

I decided to examine the lossy codecs as an experiment because they're not directly comparable and they don't support alpha channels. It's also useful to see how they perform in terms of picture quality as compared to lossless codecs. To test for picture quality I used an old After Effects trick where you place two clips on two tracks, and put the top clip in difference mode. Any differences in them will show up as colour on a black background. The brighter the colour, the more the difference. To make it easier to see the differences, I also used a levels filter on an adjustment layer to brighten up the colours and make them more visible.

In the After Effects test, the SheerVideo codec proved to be totally lossless, showing no differences at all from the Animation+ 100% compression. Given that SheerVideo is producing files of nearly half the size, this is an excellent result and validates Bit Jazz's lossless claim.

Again, as part of my experiment, it's interesting to see how the lossy codecs compared. Visually, they both produced excellent results, very similar file sizes, although the photoJPEG was twice as fast as compressing as Pixlet, which was the slowest in the test. The photoJPEG also played back a lot smoother, showing that Pixlet needs a lot more processing power to work effectively. However, in the After Effects difference test, the photoJPEG produced much superior results compared to Pixlet.

Frame from Original Uncompressed video

Difference Result for Pixlet Codec

photoJPEG

Getting back to SheerVideo, I found the installer quick and easy to use, and registration was easy. Most importantly, the SheerVideo codec has a free "Reader" so that you can play back SheerVideo encoded movies on any Mac without having to buy another copy of the codec. The codec is also easy to use. When exporting using the SheerVideo codec, you have the option of letting it pick the most appropriate variant according to it's analysis of the source video, or you can choose from RGB[A] and a number of YUV options.

It's hard to review a product like SheerVideo because there's so little to criticize. They have the free reader available and they are working on PC and Linux versions, so compatability will soon no longer be any issue at all, and the codec performs flawlessly in testing, reducing file sizes and time to compress by a significant margin. I recommend SheerVideo to anyone who is currently using the Animation codec in their workflow.

copyright©2004 Graeme Nattress