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Old 19th January 2002, 15:11   #1  |  Link
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What's more important: "Bits/pixel*frame" or "Compressibility check" ?


after I have read the DivX3 guide for Gknot, I do not know if I have understand it correctly, so:

At first, the guide says that the "Bits/pixel*frame" box, (before the 5% compr.check)should be around 0.20 if u go for 1 CD!

Then the guide talks about the Compressibility Check with the 5%!
After I have done that, GKnot shows me a value of "57,5% of 0.581 Compressibilty Test" (I know that I shouldnt go under 60% but this is not so important for this movie).
OK, I have put down my resolution so that I get this 57,5% value!
But now the value of the "Bits/pixel*frame" box shows "0.334", that's 0.134 higher than needed, isnt it?

But I cannot go up with my resolution because then I would go below that 57,5%!

So, what is more important now? The value of the "Bits/pixel*frame" box or the Compressibility Check value?

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Old 19th January 2002, 15:45   #2  |  Link
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I think if it is more bits/pixel the movie need it to compress the 57%,i always check the %
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Old 19th January 2002, 20:10   #3  |  Link
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In who wants to update the Q&A ?, diji1 (thanks, dude!) wrote the following Q&A:

Q: What does the bits/pixel*frames number mean ? What does the compression check do ? Do I need to use it ?

A: The bits/pixel*frame number provides a very rough guide as to whether the resolution is appropriate for the bitrate. It should only be used to determine the resolution settings before running a compression check. Suggested values are around 0.22 for 1 CD rips and around 0.27 for 2 CD rips. The compression check should always be run after setting this, and this value can be ignored from then on.

The compression check encodes a small portion of the movie to check how "compressible" it actually is as no 2 movies will be compressed to the same quality using the same settings. After it has finished the number next to the "load" button shows the quality of the movie as a percentage - under 65% means it is below optimum quality and you should lower resolution and over 75% means you could raise the resolution ( if appropriate - you may be happy with resolution ).

After you have set the correct resolution you must use the same field operation, noise filter and resizing settings in the first/second pass as the compression check for the check to valid.
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