About the new luma-masking algo..

MoonWalker · 27th June 2002, 23:49

I want to test the new Luma-masking in the newer XviD builds...So I got "The others"(great movie, very dark)..I was thinking to do one-pass quantizer mode at 2x with Luma enable and disabled and the then compare the final size and the visual quality..Is this worthly?

MoonWalker

soujir0u · 28th June 2002, 00:32

I tried encoding with the new CVS builds, and found that Koepi's build produced smaller files with the clip that I tried (both cases with lumi masking on). Probably due to the fact that Koepi's build uses EPSV^2 (or was it EPVS?

), not sure though. The picture quality looked about the same to me.

rui · 28th June 2002, 08:44

Quote:

Originally posted by soujir0u
I tried encoding with the new CVS builds, and found that Koepi's build produced smaller files with the clip that I tried (both cases with lumi masking on). Probably due to the fact that Koepi's build uses EPSV^2 (or was it EPVS? ), not sure though. The picture quality looked about the same to me.

This confirms some tests i have done too.

Some time ago, when Koepi (and Nic) launched their EPSZ and EPSZ^2 activated builds, i compared two files with the same size (2-pass encode), one made with Koepi's build and the other made with a uManiac's build, which didn't have EPSZ code enabled.
I even posted here that Koepi's resulting avi was keeping more details, and since the builds were equal, except for the EPSZ code, this one must be the responsible for the quality increase i was getting.

But, testing this later uManiac's builds, for the same filesize (2-pass encode) the quality between them and Koepi's build are the same now, at least IMHO.

Since i believe that uManiac's builds still don't enable EPSZ code, something has improved (new lumi?).
If Koepi, or Nic, would compile a new build, based in the latest CVS, with EPSZ enabled, i believe that we would experience a little jump in quality.

yaz · 28th June 2002, 09:59

Quote:

Originally posted by rui

... Koepi's resulting avi was keeping more details, and since the builds were equal, except for the EPSZ code, this one must be the responsible for the quality increase i was getting.

But, testing this later uManiac's builds, for the same filesize (2-pass encode) the quality between them and Koepi's build are the same now, at least IMHO.

Since i believe that uManiac's builds still don't enable EPSZ code, something has improved (new lumi?).

i confirm all above.

add.:
- the new (tested) build of umaniac seems to be quicker than the last one from koepi
- i can't notice any significant difference in quality (earlier there was, esp. in how they treated the small objects in the background), but it may come from the characteristics of the clip i selected for the test.

hmmm ... it's never obvious (for me) what do they take from each others build/improvements :-) anyway, the latest builds seem to be quite "compatible", as regards quality (imho:-))

the bests
yaz

Nic · 28th June 2002, 10:40

Because rui helps me out so much, his wish is my command

http://nic.dnsalias.com

Changes:
EPSZ and EPSZ^2 activated.
Intel Compiler 6 Compiled!

New lumi-Masking
New Mini-Calc...
(Its been a while

)

Still has my filter, but that stills has the green frame bug

Ill fix that soon.

Cheers,
-Nic

JasonFly · 28th June 2002, 11:18

Nic:
Do you develop xvid or you just compile the sources?

Nothing to do with this but when will Xvid be is final version?

Nic · 28th June 2002, 11:26

Nope, I developed my filter, but thats it, other than that I just compile the sources

(I wish I had time to do more)

I hope XviD will never be "finished" & will just keep on developing...

But things are moving forward now after a bit of a slump, B-Frames are working for fixed quants for the developers, so there not too far off from being full usable (I hope!

)

-Nic

rui · 28th June 2002, 12:13

Quote:

Originally posted by Nic
Because rui helps me out so much, ...

It was an honor, Nic.

Quote:

Originally posted by Nic
I hope XviD will never be "finished" & will just keep on developing... But things are moving forward now after a bit of a slump, B-Frames are working for fixed quants for the developers, so there not too far off from being full usable (I hope! )
-Nic

This are good news.
I've noticed that the later builds already have a new tab (disabled, for now) to configure b-frames.

Nic · 28th June 2002, 12:39

Well, only for testing purposes and the experienced (!) :

http://nic.dnsalias.com/xvid.dll

This has B-Frame support (!!!!) (just overwrite the old xvid.dll in your Windows System(32) directory)

Seemed to work fine doing a CBR encode, I used the DX50 FourCC & turned on DX50 BVOP compatability. File was slightly bigger, but quality was good !

Cheers,
-Nic

ps
I just tried to do a 2pass encode with B-Frames, went fine, but the picture did get slightly corrupt at times. Please remember, this is just for experimentation & to show the current progression of the codec.

soujir0u · 28th June 2002, 13:04

Cool, now people will stop asking when B-frames is ready. Although it isn't really ready yet...

Will XviD forever stay in alpha stage just like ICQ stays on beta?

ProfDrMorph · 28th June 2002, 13:28

would be a funny thing if my luma masking code is already working well

. Someone with Win32/Knowledge should add a temporay tab for luma masking settings. This could help us finding better constants. To be honest: I hadn't have the time to do a real test to find out which constants are good. So the values my new luma maskin code is currently using are crap to say the least. Anybody who's interested in making a temporary change to the VfW front-end can mail me in case he wants to know what values have to be changeable. I could upload a build with this front-end to my webspace ( only the "final" constants we find for luma masking should be committed to CVS and not a more complex front-end. Maybe a single slider for luma masking agressivity should be in the CVS version of XviD but nothing more. )

for any body who's interested:

http://home.t-online.de/home/profdrm..._13.6.2002.zip

this is the link to the build I made after writing the new luma masking code.

Note: please do not only compare file sizes but also quality of encoded movies!

rui · 28th June 2002, 14:33

well, i just made a small test using Nic's dll with b-frames enabled.
I can't be sure if i enabled them correctly.
I left all xvid configs at default except:

motion search - 6
enabled packed bitstream

I left the maximum b-frames at -1 (?). Probably i didn't enabled them at all?
i will try to change this value to see what happens.

rui · 28th June 2002, 14:39

Ok, i changed the maximum b-frames to 1, but Vdub crashed

Probably it will need to be modified to support xvid b-frames.

Nic · 28th June 2002, 14:55

(hmmm worked ok for me? I set the value to 100 (just as a random value). I did the encoding in VDub...(Win2k, Celeron 1000)

-Nic

rui · 28th June 2002, 15:41

Ok, i think that i got it.
I said above that i had left xvid config at default but that wasn't completely true. I had enable ME hints.

Now that i disabled them, the 2-pass encode works.

But i can't judge the video, because i am at work with my p2-350 and win95B, and it would take forever to do a test here

I just got the encode started, saw that it wasn't crashing, and came here to the forum to post this.

I used, this time, the xvid defaults, except:

motion search precision - 6
maximum b-frames - 50
packed bitstream enabled

I didn't enabled the dx50 B-VOP compatibility, since i don't intend to use divx to see the video. This is the reason because this option exists, correct? Or is there another reason?

Teegedeck · 28th June 2002, 17:31

Quote:

Originally posted by rui
Ok, i think that i got it.
I said above that i had left xvid config at default but that wasn't completely true. I had enable ME hints.

Now that i disabled them, the 2-pass encode works.

But i can't judge the video, because i am at work with my p2-350 and win95B, and it would take forever to do a test here

Hm, you might be disappointed when you come home.

After what I've read on XviD.org, it doesn't work with 2nd pass, yet.

d4Rk Ch1Ld · 29th June 2002, 01:02

I'm doing some home-testing on newest XviD (without B-frames) and i am very confused with those luma-masking... can anybody tell me does luma masking have to be enabled during 1st pass or during both passes ? (prior XviD had shadowed luma masking in 1st pass)

does your testings prove better with luma-masking off or on ?
more/less details ? corrupted frames from time to time ??

thanx for u'r time...

soujir0u · 29th June 2002, 01:06

Quote:

Originally posted by d4Rk Ch1Ld
I'm doing some home-testing on newest XviD (without B-frames) and i am very confused with those luma-masking... can anybody tell me does luma masking have to be enabled during 1st pass or during both passes ? (prior XviD had shadowed luma masking in 1st pass)

does your testings prove better with luma-masking off or on ?
more/less details ? corrupted frames from time to time ??

thanx for u'r time...

Hi, I usually turn it on for both first pass and second pass. It's main purpose is to increase compressibility, and I never got any corrupted frames with it before.

Bulletproof · 29th June 2002, 01:43

Shouldn't Luma masking be increasing bitrate? that's what Nandub was doing becuase the codec often did not give enough bitrate to less complex scenes and thus the luminance masking was compensation for that..

Gant · 29th June 2002, 06:31

hummm... and all this time i thought luma masking was suposed to ... well Bulletproof already said it...
Please people who know.. explaint it better...

Thnaks in advanced.

Gant

27th June 2002, 23:49	#1 \| Link
MoonWalker Just A Walker Join Date: Oct 2001 Location: Crete,Greece Posts: 441	About the new luma-masking algo.. I want to test the new Luma-masking in the newer XviD builds...So I got "The others"(great movie, very dark)..I was thinking to do one-pass quantizer mode at 2x with Luma enable and disabled and the then compare the final size and the visual quality..Is this worthly? MoonWalker __________________ Using : http://www.spreadfirefox.com/communi...x15/blue_2.gif

28th June 2002, 12:39	#9 \| Link
Nic Moderator Join Date: Oct 2001 Location: England Posts: 3,285	So, You're feeling daring (?!) Well, only for testing purposes and the experienced (!) : http://nic.dnsalias.com/xvid.dll This has B-Frame support (!!!!) (just overwrite the old xvid.dll in your Windows System(32) directory) Seemed to work fine doing a CBR encode, I used the DX50 FourCC & turned on DX50 BVOP compatability. File was slightly bigger, but quality was good ! Cheers, -Nic ps I just tried to do a 2pass encode with B-Frames, went fine, but the picture did get slightly corrupt at times. Please remember, this is just for experimentation & to show the current progression of the codec. Last edited by Nic; 28th June 2002 at 12:56.

28th June 2002, 14:33	#12 \| Link
rui Registered User Join Date: Dec 2001 Location: Portugal Posts: 730	well, i just made a small test using Nic's dll with b-frames enabled. I can't be sure if i enabled them correctly. I left all xvid configs at default except: motion search - 6 enabled packed bitstream I left the maximum b-frames at -1 (?). Probably i didn't enabled them at all? i will try to change this value to see what happens. __________________ Rui

28th June 2002, 14:39	#13 \| Link
rui Registered User Join Date: Dec 2001 Location: Portugal Posts: 730	b-frames Ok, i changed the maximum b-frames to 1, but Vdub crashed Probably it will need to be modified to support xvid b-frames. __________________ Rui

28th June 2002, 15:41	#15 \| Link
rui Registered User Join Date: Dec 2001 Location: Portugal Posts: 730	Ok, i think that i got it. I said above that i had left xvid config at default but that wasn't completely true. I had enable ME hints. Now that i disabled them, the 2-pass encode works. But i can't judge the video, because i am at work with my p2-350 and win95B, and it would take forever to do a test here I just got the encode started, saw that it wasn't crashing, and came here to the forum to post this. I used, this time, the xvid defaults, except: motion search precision - 6 maximum b-frames - 50 packed bitstream enabled I didn't enabled the dx50 B-VOP compatibility, since i don't intend to use divx to see the video. This is the reason because this option exists, correct? Or is there another reason? __________________ Rui

28th June 2002, 00:32	#2 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	I tried encoding with the new CVS builds, and found that Koepi's build produced smaller files with the clip that I tried (both cases with lumi masking on). Probably due to the fact that Koepi's build uses EPSV^2 (or was it EPVS? ), not sure though. The picture quality looked about the same to me.

28th June 2002, 10:40	#5 \| Link
Nic Moderator Join Date: Oct 2001 Location: England Posts: 3,285	Because rui helps me out so much, his wish is my command http://nic.dnsalias.com Changes: EPSZ and EPSZ^2 activated. Intel Compiler 6 Compiled! New lumi-Masking New Mini-Calc... (Its been a while ) Still has my filter, but that stills has the green frame bug Ill fix that soon. Cheers, -Nic

28th June 2002, 11:18	#6 \| Link
JasonFly Registered User Join Date: Apr 2002 Location: France Posts: 180	Nic: Do you develop xvid or you just compile the sources? Nothing to do with this but when will Xvid be is final version?

28th June 2002, 11:26	#7 \| Link
Nic Moderator Join Date: Oct 2001 Location: England Posts: 3,285	Nope, I developed my filter, but thats it, other than that I just compile the sources (I wish I had time to do more) I hope XviD will never be "finished" & will just keep on developing... But things are moving forward now after a bit of a slump, B-Frames are working for fixed quants for the developers, so there not too far off from being full usable (I hope! ) -Nic

28th June 2002, 13:04	#10 \| Link
soujir0u Registered User Join Date: Oct 2001 Posts: 213	Cool, now people will stop asking when B-frames is ready. Although it isn't really ready yet... Will XviD forever stay in alpha stage just like ICQ stays on beta?

28th June 2002, 13:28	#11 \| Link
ProfDrMorph fresh brains! Join Date: Oct 2001 Location: Germany Posts: 195	would be a funny thing if my luma masking code is already working well . Someone with Win32/Knowledge should add a temporay tab for luma masking settings. This could help us finding better constants. To be honest: I hadn't have the time to do a real test to find out which constants are good. So the values my new luma maskin code is currently using are crap to say the least. Anybody who's interested in making a temporary change to the VfW front-end can mail me in case he wants to know what values have to be changeable. I could upload a build with this front-end to my webspace ( only the "final" constants we find for luma masking should be committed to CVS and not a more complex front-end. Maybe a single slider for luma masking agressivity should be in the CVS version of XviD but nothing more. ) for any body who's interested: http://home.t-online.de/home/profdrm..._13.6.2002.zip this is the link to the build I made after writing the new luma masking code. Note: please do not only compare file sizes but also quality of encoded movies!

28th June 2002, 14:55	#14 \| Link
Nic Moderator Join Date: Oct 2001 Location: England Posts: 3,285	(hmmm worked ok for me? I set the value to 100 (just as a random value). I did the encoding in VDub...(Win2k, Celeron 1000) -Nic

29th June 2002, 01:02	#17 \| Link
d4Rk Ch1Ld Registered User Join Date: Jun 2002 Posts: 9	Luma Masking -> XviD I'm doing some home-testing on newest XviD (without B-frames) and i am very confused with those luma-masking... can anybody tell me does luma masking have to be enabled during 1st pass or during both passes ? (prior XviD had shadowed luma masking in 1st pass) does your testings prove better with luma-masking off or on ? more/less details ? corrupted frames from time to time ?? thanx for u'r time...

29th June 2002, 01:43	#19 \| Link
Bulletproof Registered User Join Date: Jan 2002 Posts: 318	Shouldn't Luma masking be increasing bitrate? that's what Nandub was doing becuase the codec often did not give enough bitrate to less complex scenes and thus the luminance masking was compensation for that..

29th June 2002, 06:31	#20 \| Link
Gant _ Join Date: Dec 2001 Posts: 41	hummm... and all this time i thought luma masking was suposed to ... well Bulletproof already said it... Please people who know.. explaint it better... Thnaks in advanced. Gant __________________ Jya matta, Gant