Encode keeps coming out too big (?)

[absinthe]

I've encoded probably a hundred movies with XviD and pretty much have a procedure down pat, but I've hit a snag on my latest attempt and it has me confounded.

Attempting a 2-disc encode of a 2-hour movie, using 2-pass, MPEG matrix, max B-VOPS 1, max consec. I-frames 240. My quantizer settings are the default 1/31/1/31/1/31. Trellis is on. No GMC or Qpel.

I target a bitrate for size with the built-in calc, and even though I clearly have about "1166" in the calc. box before encoding, the movie comes out about 80 MB too big and is about 1266 kbps. At first I thought I had just made a mistake, but now it's happened twice in a row. I'm quite sure I got the audio size correct as I select the exact file in the calculator.

I know setting I-frames for every 10 frames is supposed to add a bit of size, but I always do this for NTSC film encodes and things always come out just right.

Well, 'til now anyway ...

Ideers?

-abs

[Sharktooth]

:search:

[absinthe]

Yes, I've searched a read a bit, but ... :confused:

It's not as if this encode was unique. NTSC DVD rips is about all I do, and my settings never change except for the occasional interlaced video or very rare PAL DVD. If I do a 1-CD rip, I'll use H.263 and check 'adaptive quant,' and on 2-CD rips I use the MPEG Matrix and no adapative quantization.

The only thing I did differently (and beat me over the head if this would really make a difference) is that I set DGIndex to save the job using the 'IEEE-1180 reference' algorithm. Could that possibly cause this? I've gone back and indexed the VOBs again with the standard algorithm, so we'll see ...

-abs

[jon.schaffer]

My quantizer settings are the default 1/31/1/31/1/31

--> set it to 2/21, 2/31, 2/31... and see the result: you will have an undersized file... but with the max quality.


Explanation:
THIS encode is too highly compressible and the bitrate control goes crazy - it puts too many Quant1 frames which oversize the file...

You could >search< anyway. There are PLENTY of topics with the same problem...

[absinthe]

This is frustrating. I've now encoded it a third time, and it comes out too big by the same amount every time.

In between the second and third try, I encoded another movie using the same settings. It came out perfect as it usually does.

What I'm driving at is that it seems to be the material and not the settings that's causing this. The settings are the same and work in 99 jobs out of 100 ... how can the material cause the problem?

-abs

[Koepi]

We have another thread for this old, known over- and/ or undersize problem a few threads below.

Set quant range from 1-31 and set overflow treatment values to 10-20% each. This will solve your issue.

[absinthe]

Originally posted by Koepi
We have another thread for this old, known over- and/ or undersize problem a few threads below.

Set quant range from 1-31 and set overflow treatment values to 10-20% each. This will solve your issue. Thanks Koepi, I'll give this a whirl. Does your comment apply to the 1.1 version only? (I'm still using 1.0.3).

-abs

[Koepi]

in 1.0.3 it's the same.