DiVX5Enc Comp.Test Question

[Nozomi]

Sorry for the stupid question, what am I suppose to do after obtain the % of the result from the Comp.Test job output? Is this value indicate the resolution that I choose is suitable or not? So, in what range is the suitable % range? 50% - 60%? I read the /docs many times but cannot figure out what Comp.Test result for...

[jonny]

Good values are not in the docs... simply because i think is a subjective thing.
I like to encode at 60%-70%, but someone use 50%-60%, you must find what is the best range for you.
If you obtain a low comptest value, to increase compressibility you can:

- lower the resolution.
- increase the bitrate (ex: increasing the number of cds).
- use a less aggressive resize method.
- use some noise filter.

Note that, after changing some parameters, you must make another comptest.

Cheers
jonny

[Nozomi]

Jonny,

Am I right that to allow the encoding with "Less" compressibility means better quality? Beyond what % will the output unlikely to meet the traget size?

Regards,

[Acaila]

Roughly anything over 90-95% is likely to become undersized. If you use B-frames that would be somewhere around 85-90%.

[jonny]

Am I right that to allow the encoding with "Less" compressibility means better quality?


I'm not sure i've understand what you say... anyway bigger compressibility test values give better quality.

[Nozomi]

Jonny,
Make it simple, do you mean quality for Comp.Test vaule 70% is better than 50%?


Acaila,
Under what % range will be within expected target size (i.e. as calculated by GKnot)?

Can I say if Comp.Test % is in the within target size range then I can use the bit rate value for Comp.Test to proceed with the entire encoding?

[jonny]

Make it simple, do you mean quality for Comp.Test vaule 70% is better than 50%?


YES


Can I say if Comp.Test % is in the within target size range then I can use the bit rate value for Comp.Test to proceed with the entire encoding?


YES



Acaila,
Under what % range will be within expected target size (i.e. as calculated by GKnot)?



Roughly anything over 90-95% is likely to become undersized. If you use B-frames that would be somewhere around 85-90%.

[Nozomi]

Understood that 85% - 95% will become under the target size. What about over target size range?

[jonny]

DivX5 never go oversized in a 2 pass mode (at least if you don't use a VERY VERY low bitrate).