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New compression introduced, the selective ratio engine.

This new engine is a different way of approaching the video data! Selectable in three pre-defined levels, this new engine determines the balance in distincting the important screen parts from the less important ones.
Things that are not in focus in the current frame, like backgrounds, are low in detail or as we define it, of low importance to the screen.
and can be approached differenty than the important ones.

With this new compression method, setting the slider to low will lead into a scheme where the important parts of the screen are a bit more compressed than the less important ones. Compressing of low important parts can result into macroblock because the original encoder in a good encoder setup already achieved the best possible compression without loss of detail.
In medium the important parts are even more compressed than the non important parts, and in high the compression is almost done only on the important parts.

However in all three mode's the less important parts are still being compressed, because that is still mandatory to get the desired endsize.
By using this new method, the macroblocking (over compressed parts) will be less visible than with the conventional approach.
If they occur they will be more eye friendly shaped, meaning they are not 100% square but a bit more dithered shape.
The human eye will notice them less in this non square shape and thus resulting in a more pleasantly viewable version of the picture.

But all encoders are based on different motion detection scheme's, meaning there's no golden rule.
Most of the time setting it to medium will give you a very descent looking output, however with some encoders setting it to low or high might give a better quality output.
It's advisable to experiment with these settings on different discs from various distributors and view the end result on your setup by burning the video onto a rewritable disc.

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