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View Full Version : Nero recode and the endless encoding time...


Sharktooth
7th March 2005, 13:12
To make it short i'm encoding LOTR: ROTK EE DVD 1 and 3.90 FPS for a total (extimated) encoding time of 15h40m on a 3200+ CPU is not acceptable. It's ridiculously SLOW!
I'm at 50% of the second pass, so where's the real time encoding doom9 spoken about some time ago? And, most important, where's the promised patch with the encoder speed up?
FYI x264 encoded the whole DVD in about half the time...

EDIT: at 60% the extimated encoding time went up to 15h58m.

Sagittaire
7th March 2005, 13:47
ND MP: Cabac entropy coding, B-frames and weighted prediction on, deblocking filter strength -2, max number of reference frames 2, psychovisual level 2, cartoon mode (chroma improvement) on and max 2 consecutive B-frames for Matrix3/SPR. For Futurama, the deblocking strength was increased to +2 and weighted prediction was turned off (the rest of the settings were the same).

You don't must to use the best setting ... doom9 don't use the best setting for Nero AVC Main profil. For good quality/speed use:

- unconstrained (very important because Nero RC "standard" profil use high RC limitation)
- best quality (not extra)
- reference frame = 2
- bframe = 1
- cartoon (chroma) is slow but good for quality
- vector range -256+256 or -128+128
- deblock strength = 0 not adaptative
- psy mode is slow but good for quality
- weighted prediction

Sharktooth
7th March 2005, 13:52
I use 5 refs, 2 bframes, vector range -256,+256, deblock @ 1, and all options enabled.
http://www.aziendeassociate.com/recode.png

Sagittaire
7th March 2005, 14:03
5 ref frame + extra quality + high motion vection search + chroma + WPred + Psy combinaison are very slow ...

in order for increase speed change:
5 ref frame for 1 or 2 ref frame
extra quality for best quality
motion vector -256+256 for -128+128
Chroma desactived
Wpred desactived
Psy desactived

Sharktooth
7th March 2005, 14:07
If i should turn off/down all that settings i prefer using x264.
I set x264 at it's best except 5 refs and 2 b-frames and it encoded the whole s**t in half the time and presumably with better quality compared with your suggested settings.

Manao
7th March 2005, 14:17
OK, before a myth comes to live : Psy mode do not slow down the encoding process ( except if you've got something like a 16 Mhz processor, with which, indeed, you might get an encoding one second slower )

Except for that, Sagittaire's recommendations are rather correct : #reference > 2 is useless, and extra is a bit of an overkill.

WPred can be used ( it slows down only when it is used, hence not that often in fact ). Chroma will slow down encoding, but there i think it's a must.

Motion vector's min&max value won't change a thing.

BFrame > 1 won't slow down encoding.

Finally, sharktooth : don't presume that x264 with any kind of settings can be better than recode best + bframes + 2 refs + macroblock's partition, because it won't ( and that statement will stand true till x264 uses rate distorsion optimizations )

Sagittaire
7th March 2005, 14:17
in fact:
- multi-ref frame isn't high improuvement for quality (metric test)
- best to extra isn't high improuvement for quality (metric test)

Nero AVC with good speed is better than x264 (metric test) with these setting:
- unconstrained (very important because Nero RC "standard" profil use high RC limitation)
- best quality (not extra)
- reference frame = 1
- bframe = 1
- cartoon (chroma) is slow but good for quality
- vector range -256+256 or -128+128
- deblock strength = 0 not adaptative
- psy mode is slow but good for quality
- weighted prediction

Sharktooth
7th March 2005, 14:20
I didnt say x264 is better than recode... but recode needs a ridicolous amount of time to encode to top x264 and even at more or less the same quality (obviously x264 cant still reach the level of recode) x264 beats recode in speed.

EDIT: I choosen 5 refs and the other settings for testing speed.

Manao
7th March 2005, 14:33
Sharktooth : recode in good mode on a 'classic' ( 1h30 movie ) two passes encoding will yield same or better results than x264, with roughly the same encoding speed.

Sharktooth
7th March 2005, 14:37
Uhm, the differences between x264 and recode are not so evident.
Infact i couldnt tell the differece between 2 encodes.
Only examining them frame by frame i could tell which was better (recode - and that was with the settings above!).
So i dont believe recode's good mode will produce the same quality as x264. please...

Doom9
7th March 2005, 16:45
Reminds me of DivX6 in my latest codec comparison. Using all those extreme settings makes it ridiculously slow. Yet, I wouldn't say that it makes it look better.

So, even though I do not believe in PSNR as means to gauge visual quality, I suggest you give Sagittaire's suggestions a try - or use those settings I used in my comparison (3 ref frames, 2 b-frames if I remember correctly), and constrain the motion vector range as well. Just because x264 at extreme settings performs okay doesn't mean that disabling one or the other wouldn't incurr a non noticeable quality loss... after all, that's what the first pass turbo mode is based on: deactivating extreme settings don't necessarily change the output visibly.

And keep in mind that you cannot compare Recode and the Ateme commandline AVC encoder. Recode does resizing, audio encoding, real-time bitrate adjustment, preview.. all that stuff eats away your CPU cycles. And I doubt Recode will ever reach the speed the commandline encoder offers.

Sharktooth
7th March 2005, 16:57
Ah well, i given those setting a shoot... now in the first pass we're at 20 fps, like x264...
The big difference is in the second pass where x264 is able to produce more than 9 FPS while recode's "record" is 3.92...
Btw keep in mind recode is doing nothing of what you said.
It loads an AVS (with no filters except DEDecode, cropping and resize), the same i used for x264. No resizing, no audio compression and preview was disabled (as you can see in the SS).

Manao
7th March 2005, 17:03
Sharktooth : what was the duration of your test clip ( fast first pass in recode gets activated only if the clip is long enough ).

Moreover, going from extra to best doesn't change the first pass speed, only the second pass' ( it behaves in the same way as slow settings in xvid for the fast first pass : they get deactivated )

Sharktooth
7th March 2005, 17:08
The whole DVD 1 (2h02m) and btw here's x264 (athlon optimized) first pass:

http://www.aziendeassociate.com/x264.png

Manao
7th March 2005, 17:23
I guess the 3.92 figure was obtained with the previous settings ( extra, 5 refs ), am i wrong ? If so, you should get at least 1.5 times the speed of extra / 5 refs with best / 2 refs, and you shouldn't notice the difference. Good / 2 refs would give you at least twice the speed of extra / 5 refs, and still be on par ( more or less ) with x264 quality-wise.

Sharktooth
7th March 2005, 17:29
... recode should have 1 more feature: nth encodings!
ok, restarting with your suggested settings...

EDIT: Speed seems reasonably good now (almost doubled)... we'll see the final quality.

thegeby
7th March 2005, 17:55
Sharky, you lucky b*d:D Mine took 36 hours at ND Cinema quality:( (lucky I have long working hours)

Sharktooth
7th March 2005, 18:00
Well, with all the encodings i'm doing i think i will break that 36h barrier... I have 2 desktops and 1 notebook busy encoding with 3 different codecs ... :D

EDIT: First pass completed at the astonishing speed of 45FPS (what recode says) in about 1h.15m, but the second pass is below 12FPS and it's going down...
EDIT2: 10.8 and still going down...
EDIT3: 9.65 ...

Leo 69
7th March 2005, 19:30
Considering very good quality Recode gives, I usually agree to wait up to 30-40 hours... But the thing that worries me much is Recode's development progress. The thread named "Nero Recode feature list"
died on the 26 of February, and JohnV has not been posting since 21 of February. What a hell is going on ? Why keeping silence, I wonder ?
This is VERY strange behaviour from Nero, isn't it ?

Sharktooth
7th March 2005, 19:32
Yep, and the latest update did not contain any serious fixes nor the updated codec filters.

Sharktooth
8th March 2005, 02:13
Ok, the encoding is finished but the quality is exactly what i expected: inferior.
On the other hand i cant keep that PC busy for 15-16 hours for a single encode so i have no other choices.
The subtitles are another drawback. They can be seen only with the nero decoder (they works in MPC too though) but i can bear with it.
I seriously wish the promised recode update (speed!!!) and the "unlocking" of the directshow encoder and filters...