SBC - Lord of the Rings

[sid]

Hi,

i got Lord Of The Rings DVD and trying to encode it with Nandub now...any suggestions or ideas on it ?

I used Besweet for Audio with --alt-preset standard.

SBC Bitrate: ~950
Keyframe Interval: 10
Min Bitrate: 400
Internal SCD: 100%
Space KF: 24
EEP&QC: Full - Antishit 21-MinQ 0-Mm 0

MBCM: 30%
CC: 50 %
LC: 10 - 30
End Credits: 350
Filters: HP 270 - LP 2500
BR: Proportional
Smoother: 3%

Span: 8
Sensitivity: 10
MBDLL: Both at 300 = off
CM: 30%
BRM: unchecked

Payback Delay: 120
Corrections on low bitrate: both off
Gauge: 30 - 35 - 80
KF Boost: 5%
Freeze: 0%

DRFs: all default

Scene change treshold: Alternate 35
Crosspoint: 450

Filters: Precise Bicubic Resize

I think i dont have to mention that it is a fast movie with tons of high bitrate scenes and almos 3h.

I am trying to get it on 2cds with MP3, i know you can get good quality on 2cds.

Any ideas which settings i could improve ?

Btw i also tried to leave MBCM, CC and luma switched off, but it didnt give me great improvements, i even got a worse quality.

[iago]

@Sid

I haven't encoded that movie and don't know much about its compressibility (well, it seems a hard case actually); but generally speaking about your parameters, I guess there *are* a few things you can do to improve your quality ;):

1.) Try changing your DRF settings: DRF: 2-8 or 2-10 / keyframes quality: 2-4 or 2-6 for example (especially for "keyframes quality" the default values (4-31) are senseless).

2.) First try "without" anti-shit and capping your keyframes as mentioned (2-4 or 2-6).

3.) Min. bitrate 400 may be too high, try lowering it to sth. like 300-350 (and also you can try setting your high-pass value the same as this one).

4.) encode end credits at 150 or 200 (350 is too high imo if you don't "especially" want higher quality credits.

5.) Leave KF Boost at 0.

6.) Enable "Corrections on Low Bitrate Conditions" and check "Modulated" too.

7.) Curve compression 50% is absolutely too high imho. Lower your crosspoint value (not lower than 350 though for 2CDs) and try calculating CC again until you reach a lower CC value.

8.) The default value "45" for payback delay is fine imho.

9.) Also you can consider using "Neutral Bicubic" (0,0.5) or "SimpleResize" instead of Presize/Sharp Bicubic to increase compressibility.

10) I don't know what resolution you are using but you can also consider lowering your resolution in some hard cases to achieve better quality.

11) You can also increase your low-pass value to 3000-3500 for allocating more bits to high-bitrate scenes.

Phewww, look at this! It's been a long long list here and I stop! ;) Briefly, there are many tweaking possibilities to get better quality with SBC, but also don't forget the limitations of the codec, where even SBC cannot do much to solve these problems (smearing, blockiness, etc.).

Good luck! Hope you get better results in your future tries ;).

regards,
iago

[sid]

ok i will try your suggestions in an over-night encode :D
thanks so far

i had especially problems with blockiness in some high bitrate scenes, smearing in normal scene, and moving pixels when they show forrest from a far distance..

btw i had the cc was not calculated i just set it to 50% :p i tried to achive better quality with it, but didnt work so far :rolleyes:

[Slogra]

I encoded Lord of the Rings some time ago at 704*???. But it was a bit blurry (athough i used sharp bicubic resize). So if i would do it again, i would have chosen a lower resolution.

[sid]

I use 640x272, i get a good picture now and acceptable blocks, but there are still this pixel jumping problem.

[JasonFly]

@iago:
thank you for your help with shit keyframes.
The lowering keyframe quality trick works fine.
Could I set it to min=2 and max=2 for 25 cd rip or will it increase too much filesize?

But my main question is not this , you said:
Enable "Corrections on Low Bitrate Conditions" and check "Modulated" too

I didn't find in any guide the meaniing of these parameters.
What do they do?

Thank you very much iago.you're the master of sbc!

PS:
encode end credits at 150 or 200 (350 is too high imo if you don't "especially" want higher quality credits
Putting a 150 bitrate for credits whereas min bitrtate is 300 will crash nandub at the first frame of credits.
And the value 150 is too low imo.Because you won't see anything. Just cut the credits instead of using such a low bitrate.

[iago]

@JasonFly

"...Finally corrections on low-bitrate conditions: This is to prevent a side-effect of the minimum allowed bitrate. At very low bitrates the curve gets lower than minimum allowed bitrate. The codec is left at that bitrate and the deviation is updated accordingly but the gauge has the tendency to augment rapidly in these cases which can cause an overuse of bits in the next "normal" scene. If you activate this feature you should activate modulated as well." from Doom9's Nandub guide: www.doom9.org/nandub.htm

Also you can download Koepi's "Nandub Options Explained" document from: http://mitglied.lycos.de/koepi/

thank you for your help with shit keyframes. The lowering keyframe quality trick works fine. Could I set it to min=2 and max=2 for 25 cd rip or will it increase too much filesize? Are you kidding/pulling my leg Jason? ;) Come on man, what's a 25 cd rip?!! Well, of course it will affect file size (but 25 CDs would suffice anyway - LOL! :)); however I don't see any reason to set the maximum to 2, 2-4 would be OK in most cases (for both 1CD and 2CD encodes) imho.

As for the credits, I have never had any crash with credits bitrate 150 so far ;). But it's a matter of taste of course and imo depends on the credits actually (for example, for Matrix end credits I wouldn't use 150 certainly and set a higher value).

And finally, I'm absolutely not a "master" but just an old "user" of sbc ;).

I'm glad you're happier with the results you get now.

regards,
iago

[JasonFly]

Scuse me I wanted to say 2cd rip
Thank you

[Slogra]

I set the credits start at the scrolling credits (frame 248532). I used 20% for that.
Since movie ends more or less unexpected, i thought it was nicer to do it like this :D .

But then again, I don't think the credits matter that much because it's only a fraction of the whole movie :rolleyes: .

[sid]

What about the jumping pixels ? Does anyone have a clue which setting has influence on them ? I mean i dont talk about big moving blocks...they are just small pixels which make the background seem to move slowly line for line sometimes...i cant express what i see exactly but maybe you know what i mean.