Need advices for a movie encoding on 2cds using xvid 1b2

[jp80]

I read the doom9 guide, advicing to keep the bits/pixel around 0.25 and to use the lanczos resizing filter the for a high bitrate movie on 2 cds.

But this is in the case where a single mp3 track is used for audio, whereas in mine I'd like to mux the avi file with two ac3 tracks...

So if I plan to put my movie on 2cds, will it still have a good quality in xvid 1b2 if I set the resolution to keep the bits/pixel around 0.17? And knowing it should have an average bitrate around 1051kB/s according to GK, as 600mb/1400mb will be already taken by the dual ac3, should I still use the lanczos filter, or bicubic?

[Tuning]

Note that GK currently doesnot support XviD 1.0b2, So after doing calculations with GK you have to manually use VDM for encoding.
Tutorial here (http://www.doom9.org/xvid.htm)

As far as GK don't support XviD 1.0b2 you cannot perform compressibility test, Which is the solution to your questions.

If compresiblility test returns around 60-65%, then you can undoubtly go with encoding at current bitrate. At higher values (>75%) of compressibility, you are wasting bitrate. Look the above linked guide.

Hope that helps...:)

[jp80]

Now that latest GK is now compatible with xvid 1.0, I still wonder if my bitrate of 1051 kB/s gives enough quality for a picture resolution output at 704x368, and which resize filter should I use with it?

[Tuning]

For deciding what bitrate is required for a particular setting, do a compressibility test. If the compressibility test returns value around 60-70% or more you can proceed with current settings as good quality encode will be resulted. If it is around 80% then your bitrate is huge and you are wasting bits with such a bitrate. There is a Gk tutorial explaining use of XviD here (http://www.doom9.org/gknot-xvid.htm).
Read this guide and follow the instuctions presented by doom9. Then everything will be OK!.

Bye.:)

[iago]

[...]If it is around 80% then your bitrate is huge and you are wasting bits with such a bitrate[...]If quant 2 (%100) means the best possible quality with the given settings, why should he be wasting bits with a compression ratio of %80 (especially as long as resolution is high enough and sufficient space is spared for high-quality audio)! ;)

A matter of personal taste, actually...

Though I agree that XviD with b-frames gives quite pleasing results even with a compression ratio of ~ %50.

regards,
iago

[Tuning]

A matter of personal taste, actually...

Hi iago, i agree your comments. But if you consider a general GK user the size prediction is important. Which can only done in 2-pass and some savings in bitrate can be done with compressibility. That is what i mean.

Bye.