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MPEG-2 Compression
The first Casablanca model and most PC cards make use of the Motion-JPEG compression technique. This technology offers a DV comparable picture quality at roughly 3.5 MB/Sec., making a 9 GB hard-disk capable of storing about 40 minutes of video.
Wavelet is another, not as common compression technology working with a similar effectiveness. Both Motion JPEG and Wavelet compress each single video picture (50 pictures a second) independently. So far, this has been the only payable method of storing video digitally on hard-disk for editing. MPEG-2 on the other hand, compresses more effectively. This technology compares the single pictures with (e.g.) 20 neighboring pictures and saves the changes in the video signal. With a camera panning, the technique saves the information coming into the camera's view while with a stationary camera filming a football game, it saves the movements of the players. This method is very complex and has in the past therefore only been available for professionals. Advances in semi-conductor technology have made it possible to manufacture cheaper systems for end users. MPEG-2 is far more effective than Motion-JPEG - roughly 3 times more so. This low data rate is, in addition, a condition for real-time effects because current hard-disks are not capable of delivering 2 high quality Motion-JPEG / Wavelet picture-data streams reliably. This data rate is reduced with MPEG-2 - even the IDE hard-disks used in the Casablanca Avio model can work seamlessly with 2 MPEG-2 picture streams. MPEG-2 is also the method used by DVD video players and the new digital television. The DVD (Digital Versatile Disk) has been received extremely well by the press for it's very high picture quality. Casablanca Avio and Kron allow a far higher data rate than DVD, leading to an even better picture quality than DVD's picture quality. Even the Avio model reaches broadcast picture quality. Casablanca Avio and Kron utilize a true MPEG-2 data stream. Limiting to technically simpler methods ("I-Frame only") would have resulted in a loss in picture quality. Picture-perfect editing ("editable MPEG") therefore requires an enormous effort in terms of development and we are proud of our success.
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