2 pass encoding serious problems!

[Baldur]

Hi everybody.
I'm experiencing serious problems in encoding with divx 4.11 two passes method!
I've got to compress a 112 minutes long movie, to put it on a single 700MB cd. I'm using wma V2 64Kbit/sec for the audio.
That means that the final audio file will be exactly:
8KB x (112x60)secs/1024 = 52.5 MByte
so I have exactly 700-52.5=647.5 MByte of free space for my video file. Right?

That means:
647.5x1024x8=5304320 Kbits
and then
5304320/(112x60)=789,33 Kbit/sec

Well, i used this settings, but the result was a 1,89Gbyte large file, without audio!
Can someone help me? Thanx

[SithUK]

Have you tried using a BitRate calculator? I don't believe you can use as simple formula as you have outlined to calculate a final Avi file size.

Sith

[Baldur]

Though I don't believe that much in bitrate calculators, (due to the fact that DivX doesn't maintain a constant bitrate throughout the whole file), i used divx4 bitrate calculator v2.0, and it gave me a value of 809,77 Kbit sec, that's bigger than the one i used.
So I don't think that was an error of bad formulas!!!
A bit is just a bit! So if u use a simple formula, like I do, u'll have a value using which u should be able to obtain a file smaller than the size u want (divx is a VBR codec). So u can increase the value u obtain, by 10 or 20 bit/sec, and be sure it'll work right with one pass encoding!
I think that mine is a problem of two pass settings!

[khp]

What tool did you use ?

What settings did you use ? mQ, MQ, keyframe interval,,,

[Baldur]

800 Kbit/sec
Maximum Keyframe interval 100 frame
Maximum quantizer 12
Minimum Quantizer 2

Well, I went on tryin' and finally had a result near to what I needed.
I have to say that probably the error was due to bad Xmpeg settings. So I did once more the second pass, and obtained a file 724 MB large, with audio. But that's still too much for a cd. And I obtained it using the same settings that gave me a 694MB large file with one pass encoding. So now my question is:
when I do the 2 passes encoding, is it true that I shall use a value lower than the one I could use (for the same movie) doin' the single pass?
Thanx everybody