Can't get the right size MPEG2!

[ashsharma]

This is starting to drive me nuts now.

I'm converting a divx file to MPEG2. The film is 1:41:45 long, I've used bitrate calculator to figure out the bitrate and get an average of 5534 which I'm using for the vbr average bitrate in Tmpgenc. But keeps producing a file that is too small (2.2-2.4Gb).

What am I doing wrong?

Also when changing the audio on bitrate calculator, what should I be setting the audio at? The source bitrate?

Please help, I'm going insane!

[Gazorgan]

Nothing.

You set a max bitrate. Sometimes there's simply not enough there to encode. If your resolution was 352x240 then I doubt you could use all that bitrate. Even 352x480 interlaced can't use a bitrate as high as 5500.

How does the MPEG look? Ideally it will look just like the AVI.

[ashsharma]

The source avi is 576x320.

The Mpeg looks ok, but I'd like to get it to the highest quality before I burn it.
I'm going to try running it again, but what should I set the audio to in bitrate calculator? I might be setting this too high.

[GKar]

FYI, Bitrate Calc is only valid for CBR, its unreliable in VBR because it depends on the amount of action in the film I believe. VBR calculations are trial and error. I set my Dazzle DVC II hardware encoder close to maximum bitrate when I capture, around 9.7 MB in VBR mode and if the MPEG2 is too big I shrink it with DVDShrink or author it to 2 DVD's. I always record DVD audio at 224kb and sample at 48khz.

[ZippyP.]

What type of VBR are you using? If you're using 2-pass VBR then setting the average bitrate will produce a file very close to the specified size. If you're using some other type of VBR then file sizes are unpredictable.

224 is the typical bitrate for MP2 audio which is what TMPGEnc produces.

[ashsharma]

Yeah I'm using 2 pass VBR, I've done it a few times now and the largest I can get the MPeg is 3.57GB. I've been using the value from the bitrate calculator. But also if I try using the wizard in tmpgenc, if I use this value for the average bitrate it says that the resulting mpeg will take up 104% of a DVD.

I can't think what I'm doing wrong.

[funkguy4]

Yo. Since your source is already kinda semi low res. you probably don't have enough to use those bits up with. How aboot you get ANOTHA movie to put along with it. Then you can file ~ 4.3 GB

[ashsharma]

Yo. Since your source is already kinda semi low res. you probably don't have enough to use those bits up with.

OK that might be it. How can you tell whether it's low res or not?

Also, can I convert any avi to widescreen ratio? or does it have to remain the same as the source?