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05-26-2004, 05:58 PM
maurus maurus is offline
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Two questions:

1) Sometimes, the video file created with Mencoder is more short than predicted. With the same bitrate for 1 CD 89 min:

- With QuEnc=722 MB OK
- With Mencoder (with the temp.conf of MencodeMe, template DVD): 600 MB

It is posible?
I have too many buffer underflow errors. It is the cause of the minor size? It lost frames?

2) Bitrate. I use overscan factor=2, check 16:9 source to LetterBoxed 4:3 and use those settings of new MenCalc for my settings in the file .conf of MEncoder. The crop is 448x432 and then expand with black to standard 480x576.

I must change to up the bitrate? I see how certain files are also more short of the predicted size. It is also the cause of the minor size?

Do you understand me? My english is so poor...


I changed keyint=15 for PAL (GOP size)
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Someday, 12:01 PM
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05-27-2004, 03:52 AM
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I assume the template u used got a lmin value of 1 (lmin=1) ... so do another test using lmin=0.5 and try again. BUT Phil reported some days ago that lower lmin values at 1cd encodings (= low avg bitrate) do mess bitrate curves up. I dont remember if that only happened at 1pass VBR encodings.

So do a test and lower the lmin value as desribed above and do a 2pass encoding (generally recommended when using mencoder).

That was exactly the reason why I made packshot purposed only for dvd encodings (=higher avg bitrate), as no matter which parameters are used:
WE STILL didnt found the "general" full k(S)VCD compilant parameters where all these issues do not appear in general:
a) No buffer underruns
b) constant quality in the whole stream
c) no max bitrate overruns (max 2500)

I did read in here so many issues related to 1cd encodings using mencoder that in the "parameter experiences"-state now ... I do not recommend using mencoder at 1cd encodings. But that could change very fast as its a matter of figuring out the perfect paramaters for that format.
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05-28-2004, 03:00 AM
maurus maurus is offline
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Very important lmin=0.5.

The size now is correct, it is the same of the file created with QuEnc.


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