Has it got sense setting the bias in DVD-RB?

[tom942]

I was reading the guide that is available at the main site about encodig with CCE and how to set CCE's bias, and I saw that if you've got, for instance an average bitate of 3300 kbps, you should set it to 33 or if you've got 2900 kpbs, you should set it to 29.

Like is a relative old guide:

Has it got sense to set it that way under DVD-RB?.

Could it be applied the same principle to HC?.

Or is it better to left the default setting (20)?.

I've been doing a search, but all the threads that I found about this are relative old, about year 2002-2003.

Greets and :thanks:

[Boulder]

I think you're confusing flat part priority with VBR bias, at least that's what I gather from the values 29 and 33.

I personally have used bias 0 for a long time now. With such low bitrates that DVD5 offers most of the time, there's no need to apply any bias towards CBR. HC's internal default is 0 at the moment.

[tom942]

This is the guide where I found that, Boulder:

http://www.doom9.org/mpg/cce-roba.htm

Also add the following line to the [item] section of each file you're encoding:

vbr_bias=30

Where you replace the value of 30 according to your bitrate. The higher your bitrate the higher this factor. For a bitrate of 4000kbit/s you'd use a bias of 40, for a bitrate of 3000kbit/s you'd use a bias of 30, etc. Trilight has compiled a nice page outlining how the bias can be chosen.


But I suppose it is outdated.

Then, do you use 0 instead of the "default" 20 that comes set in DVD-RB?.

[Boulder]

Yes, I use 0 in DVD-RB and in my manual encodes. The same goes for CCE and HC.

[tom942]

I have done the same DVD with Bitrate Distribution enabled in DVD-RB (100% sample), but this time, with the bias at 0, and it works really fine.

Thank you for your suggestion. This way I don't have to rack one's brain :).

Edit: It worked fine with HC, but not with CCE, in some segments it does weird things, so I leave it to Bias 20 in CCE again :(.