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Extensive tests without vrc_minrate
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Lots of screenshots from 3 different streams coming on the next posts :) Cheers, Bilu |
Test 1: Dark underwater scene
Conclusion: lmin=1 is recommended. scplx_mask needs naq, but doesn't bring value. lmin=2.49:vbitrate=3000 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1500 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1500:vmax_b_frames=2 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=3000 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1500:scplx_mask=0.3:naq http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1500:scplx_mask=0.3:naq:vmax_b_fra mes=2 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1500:scplx_mask=0.3 http://www.digitalfaq.com/archives/error.gif |
Test 2: Clean anime
Conclusion: again the same as in Test 1. lmin=1:vbitrate=1000 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1000:vmax_b_frames=2 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1000:scplx_mask=0.3:naq http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1500 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=1500:vmax_b_frames=2 http://www.digitalfaq.com/archives/error.gif lmin=1:vbitrate=3000 http://www.digitalfaq.com/archives/error.gif |
Test 3: High bitrate peaks
All tests done with vbitrate=3000:lmin=1. Conclusions: lmax is REALLY needed. Can't wait to see vrc_buf_aggressivity working :!: Lmax values can't be too low or you'll get buffer underflows. I could get up to lmax=6 in this stream, but I wanted to see how far would the quants go :) Best combo IMHO seem to be using lmax together with vrc_eq=1, it doesn't overquantize for so much time as with others. lmax=31:vrc_eq=tex http://www.digitalfaq.com/archives/error.gif lmax=31:vrc_eq=1 http://www.digitalfaq.com/archives/error.gif lmax=10:vrc_eq=1 http://www.digitalfaq.com/archives/error.gif lmax=10:vrc_eq=1:vmax_b_frames=2 http://www.digitalfaq.com/archives/error.gif lmax=10:vrc_eq=avgTex http://www.digitalfaq.com/archives/error.gif lmax=10:vrc_eq=tex^0.5 http://www.digitalfaq.com/archives/error.gif lmax=10:vrc_eq=tex http://www.digitalfaq.com/archives/error.gif |
For this last tests, did you use the exact same scene for each BV screenshot :?: 8O
This encoder behaves so much different with different settings... :roll: |
Test 1: dark underwater scene from "The Abyss"
Test 2: scene from "Read Or Die" anime Test 3: intro from "Neo Genesis Evangelion" Same scene is used during each set of tests. Bilu |
I tried your settings, but they're giving me buffer underflows the whole way down... :roll:
i'm now using the settings from the guide by rds_correia, and so far I have no buffer underruns. I hope I won't get those bitrate peaks... :roll: Edit: I just encoded 50% of the movie and stopped the process, just to see if the average bitrate would be fine. I encoded with vbitrate=3000... after 50% BV says the average bitrate is 1620kb/sec... Is that normal? I know the ratecontrol doesn't work yet how it is supposed to be... However bitrate peaks are already above 8000. I fear that when I increase vbitrate I'll get bitrate above 9000kb/sec... :roll: |
Don't set vrc_minrate.
About underflows, don't limit max quantizers. The last settintgs on rds_correia guide were my settings until vmesquita and incredible found out that vrc_minrate screws avg bitrate guidance. I confirmed it here: http://sourceforge.net/mailarchive/m...msg_id=6860343 Bilu |
Alright, thanks bilu... Now these are the settings I'm using currently:
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of=rawvideo=1Output is KDVD by the way... Edit: Oh 2 more questions... I get 1 buffer underflow at the very beginning of the movie right before mencoder starts working. is that normal? I get that with every settings I used so far. And: Is there a way to raise DCT-Precision to 9bit? |
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Bilu |
Unexplored territory:
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Bilu |
bilu,
already tested without minrate, and yes, works (as expected). I get (in BitrateViewer) min bitrate about 190, with a vbitrate=1500 and maxrate=9800 (KDVD). I'm afraid that with lower vbitrate and/or maxrate (for KVCD) it will go under 150 (and with this minimum bitrate my player freezes from time to time). |
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Constant noise may be the answer to keep a bitrate over 150 Kbps. Bilu |
Yes, I remember using noise in the beginings of ffvfw encodings (a looong time ago :roll: )
It could be adjusted in a way. But I didn't like the output (maybe added too much noise). Do you think that it would be really necessary to add noise to avoid too low bitrate?. Yes, I know the answer: yes, if I want to avoid too low bitrate, this is a way. My question is: is it the only way?. |
If you can't use the encoder's minrate setting then you'll have to prevent "no-motion" situations that would generate bitrates lower than 150 Kbps.
Now imagine you get a stream with a dark stalled part of a few seconds, like a room with the lights out. How can you deal with it to avoid "no-motion"? Noise. It's the only way. Bilu |
And the funny thing is, even if mencoder during encoding reports buffer underflows .... sometimes afterwards inspecting in BV :arrow: Everything is totally normal :?
BTW ... I did yesterday some comparisons to CCE 2.50 and there the Q curve behaves exactly as it should do in mencoder. 8O (But CCE 2.50 does still have problems with patched matrixes ... well in my case... if std. CCE is used, everything results perfect) |
Did anyone experience some kind of a pulsing video with mencoder? :roll:
because when i look at my mencoded movies they look like they have some kind of pulsing/flashing effect. It's hard to explain, but artifacts do appear in the background in certain intervalls. It also seems like the picture gets darker and lighter... weird huh? I'll post some samples tomorrow! |
Hey J3elly,
I haven't experienced such an issue with mencoder but I must say I have seen something like that being posted on the forum long ago and it wasn't mencoder we were testing back then. Could it be not using B frames?? I think we need kwag or jorel to look at your post. They'll remember for sure. Cheers |
Hmm,
Could it be a very looonng GOP size?? Just a thought. C ya |
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If you are encoding at high resolutions, you must use a larger size for VBV buffer. Look a the man page of mencoder, and search for "vrc_buf_size". -kwag |
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