2 Pass Variable Bitrate

[Nerfboy]

Would anyone recommend 2 pass variable bitrate over constant when encoding? And why?

[Solitaire]

Hi,
I always use 2P VBR on all my dvd's which are in excess of 60 minutes duration. Main reason is file space compared to quality. If the top bit rate is kept in region of 8000 and the lower rate is reduced compared to file size (duration) then it is quite possible to get a good 90 minutes duration at very good picture quality. The 8000 bit rate will have to be reduced as the duration approaches 90 mins as the lower bit rate doesn't want to be reduced lower than 4000 - 5000.
A 120 min duration file encoded in 2P VBR will generally look much better than one encoded at CBR due to the extra bitrate available for the fast movement sections and the large areas of any moving green coloured objects like tree or long grass blowing in the wind or being panned across. The prime factor is file size, there is only about 4.4Gb file size available on a single layer dvd so VBR has an advantage over CBR when the duration exceeds 60 mins and even more so as it exceed 90 mins and approaches 120 mins.
Keith

[Nerfboy]

Thanks for that. Although now I am trying to encode with 2 pass and it is telling me "You cannot use 2-pass mode and multiple file output together. Do you want to use single file mode?"

Is that b/c I am selecting m2p and not m2v?

[STORMDAVE]

You're using ProCoder Express right? Ignore that error and press Yes, it will do 2 pass.

[Nerfboy]

Is single file mode something you want to avoid?

[Operater]

Hello everyone, from warm Greece.. Happy to 'meet' you there...

I have a similar question... What more gives the 2 pass variable from the single?
It helps quality, I think, but especially where?


Sorry for my english... I'll try improve them...

[STORMDAVE]

Nerfboy I always ignored that popup and PCE always rendered 2pass.

Operator, in 2pass mode, the encoder reads the complexity of the scenes on the first pass (to see where to use high and low bitrates) and on the second pass it does the encoding.

If your program is 60 minutes long and you use 2pass you're not goin to notice a big difference. It comes into play when you try to fit 2 hours on a DVD5. I always use 2pass when above 90 minutes.

[Nerfboy]

Cheers for that, I am going to get Procoder 3...anything I need to know about that? What advantages does it have over PCE...

[STORMDAVE]

For starters it supports many more formats and has Mastering setting for MPEG2. Also has DVD Preview Target which uses all cores to render to MPEG2 (There is no 2Pass for this, though).

I think you can upgrade from ProCoder Express to PC3, find a reseller.