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MoonWalker
10th April 2002, 12:59
I just finished a 2-pass encoding of Dracula 2000 (Very Very compressible movie)...Well when a encoding ended the overflow was 12325. Is this normal?

My settings :

Wanted size : 1003574 Kb
Actual size : 1003618 Kb

2 Cd Rip
Motion : 5
Quant : MPEG
I-frame Quant min/max : 2/4
P-frame Quant min/max : 2/31
I-frame boost : 20%
Alt cc used
Agression : Low
High : 300%
Low : 100%
Strengh : 50% (BTW are these sensible values?)
End Credits I-Frame Quant 20 P-Frame Quant 20

And here are the last lines of the debugview :

2nd-pass: quant:20 MPEG inter stats1:96 scaled:96 actual:96 overflow:12325 credits
2nd-pass: quant:20 MPEG inter stats1:96 scaled:96 actual:96 overflow:12325 credits

Quantizer distribution for 2nd pass:
[356] Q:2:110476
[356] Q:3:23359
[356] Q:4:1

I am using Koepi's XviD-06042002-1..

MoonWalker

-h
10th April 2002, 13:21
I just finished a 2-pass encoding of Dracula 2000 (Very Very compressible movie)...Well when a encoding ended the overflow was 12325. Is this normal?

An overflow of 12325 means the codec was 12325 btyes away from where it wanted to be. 12325 out of 1027659776 bytes isn't too bad :)

-h

sierrafoxtrot
10th April 2002, 13:52
i've noticed that when you use const Q for credits, the overflow looks like that. it's pretty normal, and filesize accuracy isn't compromised.

Kyo
10th April 2002, 17:47
@MoonWalker

A question of a lost Boy :( :
where do u get the values of: ?

Quantizer distribution for 2nd pass:
[356] Q:2:110476
[356] Q:3:23359
[356] Q:4:1


Thanks
:p

MoonWalker
10th April 2002, 20:32
@-h

Thanks :)

@Kyo

I got this values from the three last lines of the Debugview...

MoonWalker
10th April 2002, 22:22
An overflow of 12325 means the codec was 12325 btyes away from where it wanted to be. 12325 out of 1027659776 bytes isn't too bad

But wouldn't be better if these bytes where gone to thes previous frames?So we'd end with overflow 0??Why to loose these bytes?I am not a coder so I don't know why this is happening..Maybe is the codec itseld like that

MoonWalker

-h
11th April 2002, 01:03
But wouldn't be better if these bytes where gone to thes previous frames?So we'd end with overflow 0??Why to loose these bytes?I am not a coder so I don't know why this is happening..Maybe is the codec itseld like that

Well 12000 bytes adds up to about... 2 frames. It's completely normal behaviour - the codec can't be "spot on" since it can't know exactly how many bits a frame will use before actually encoding it.

-h

MoonWalker
11th April 2002, 08:53
2 frames?:rolleyes: I guess I have to think before I write :o :) Thanks...


MoonWalker