digitalFAQ.com Forums [Archives]

digitalFAQ.com Forums [Archives] (http://www.digitalfaq.com/archives/)
-   Avisynth Scripting (http://www.digitalfaq.com/archives/avisynth/)
-   -   CQ vs. CQ_VBR ... VERY INTERESTING... (http://www.digitalfaq.com/archives/avisynth/1910-cq-vs-cqvbr.html)

kwag 12-24-2002 04:31 PM

Quote:

Originally Posted by SansGrip
Quote:

Originally Posted by kwag
Note: I just realized that the samples I encoded above were all done with "High quality" and not "Fast" on motion estimation in TMPEG.

As long as both CQ_VBR and CQ versions were done the same, I don't care -- I'll wait twice as long for a better encode if that's what it takes 8).

They were both done identical. :wink:

-kwag

SansGrip 12-24-2002 04:37 PM

Quote:

Originally Posted by kwag
They were both done identical. :wink:

Ok, now I'm starting to get excited by this :D. Time for me to try Resident Evil at 704x480... Let's see if it really is the resolution that makes the difference.

kwag 12-24-2002 04:42 PM

Quote:

Originally Posted by SansGrip
Ok, now I'm starting to get excited by this :D. Time for me to try Resident Evil at 704x480... Let's see if it really is the resolution that makes the difference.

We're all hyperventilating at this momemt :mrgreen:

SansGrip 12-24-2002 04:45 PM

Quote:

Originally Posted by kwag
We're all hyperventilating at this momemt :mrgreen:

Wouldn't this be a great Christmas present? ;)

Right now I'm figuring out a good CQ_VBR for R.E. at 704x480, 1 disc. Then I'll try to get as close to that size as I can with CQ...

SansGrip 12-24-2002 05:13 PM

Anyone else noticed that sometimes several CQ values (in my case 52-54) produce almost identical file sizes?

kwag 12-24-2002 05:35 PM

Quote:

Originally Posted by SansGrip
Anyone else noticed that sometimes several CQ values (in my case 52-54) produce almost identical file sizes?

Yes! It's a weird unlinear scale. Probably with "null" points throughout the complete curve :?. Maybe caused by the KVCD Q Matrix :?:

-kwag

gonzopdx 12-24-2002 05:50 PM

So how will using CQ instead of CQ_VBR affect the prediction? Will KVCDP be able to be used the same way or do we have to do manual prediction?

muaddib 12-24-2002 05:53 PM

Quote:

Originally Posted by SansGrip
Quote:

Originally Posted by kwag
We're all hyperventilating at this momemt :mrgreen:

Wouldn't this be a great Christmas present? ;)

:lol: I LOVE this forum!!! :lol:

SansGrip 12-24-2002 05:58 PM

Quote:

Originally Posted by kwag
Yes! It's a weird unlinear scale.

Might make prediction harder. But I like a challenge 8).

I just found correct sample sizes for both CQ_VBR and CQ, but am having mixed results. While one particular frame is much improved with CQ (with CQ_VBR it is almost entirely made up of macroblocks), generally the CQ version is slightly more blocky. But this is with motion estimation -- I'm currently reencoding at high quality to see if it makes a difference.

kwag 12-24-2002 06:08 PM

I have a feeling that CQ mode has a better bit rate allocation than CQ_VBR. That's why artefacts are less noticeable than with CQ_VBR. That's just my thought :o

-kwag

black prince 12-24-2002 06:16 PM

@Kwag and SansGrip,

Used 704x480, GOP=1-2-12-1-24, commented Blockbuster noise,
2 CD's with 112kb audio and CQ=85. The movie, Vanilla Sky,
2hr 19 min and the verdict is WOW great 8O Looking at BitRate
Viewer, the average Q = 2.87. I wish there was a corrulation between
picture quality and Q. :? Fast action scenes has the lowest Gibbs noise
I've seen, even better than KVCDx3 (528x480). This template seemed more
compressable the the PLUS templates. I going to try this same
resolution for 1 CD. :D I too would like to know what file prediction
formula should be using for this :?:

-black prince

SansGrip 12-24-2002 06:18 PM

As a side note:

CQ_VBR 6.5 (motion estimation) = 11,910,158
CQ_VBR 6.5 (high quality) = 10,610,730

Edit: Also:

CQ 56 (motion estimation) = 11,796,690
CQ 56 (high quality) = 11,303,978


Haven't done a visual compare of them yet...

SansGrip 12-24-2002 06:29 PM

http://www.digitalfaq.com/archives/error.gif

http://www.digitalfaq.com/archives/error.gif

I think I'll let the pictures speak for themselves :).

gonzopdx 12-24-2002 06:47 PM

So how will using CQ instead of CQ_VBR affect the prediction? Will KVCDP be able to be used the same way or do we have to do manual prediction?

SansGrip 12-24-2002 07:14 PM

Quote:

Originally Posted by grivad
So how will using CQ instead of CQ_VBR affect the prediction? Will KVCDP be able to be used the same way or do we have to do manual prediction?

Theoretically you should still be able to use KVCDP. When it says "CQ_VBR", pretend it says "CQ" ;). You might want to set the start value to 50 instead of 25, though, or it could take a while to get accurate.

kwag 12-24-2002 07:41 PM

Quote:

Originally Posted by black prince
I too would like to know what file prediction
formula should be using for this :?:

-black prince


I currently started to encode "K-19" at 352x240 LBR just to test the formula on CQ. It should be the same. Let's see how far off is the final target to the predicted size. I'll post result here when it's done. In about 2 hours.

-kwag

kwag 12-24-2002 07:45 PM

Quote:

Originally Posted by SansGrip
I think I'll let the pictures speak for themselves :).

Oh boy, they don't speak, they SCREAM :!: CQ CQ CQ ( Just like a ham radio operator ( me included :wink: ) :mrgreen:

SansGrip 12-24-2002 07:50 PM

Ah, kwag, there you are -- I thought you'd gone missing ;). What... spending time with the family on Christmas Eve instead of TESTING? :mrgreen:

Quote:

Originally Posted by kwag
Oh boy, they don't speak, they SCREAM :!:

heheh yes it's pretty persuasive. I'm currently testing 528x480, and then will try with different (more sedate) source material.

kwag 12-24-2002 07:55 PM

Quote:

Originally Posted by SansGrip
Ah, kwag, there you are -- I thought you'd gone missing ;). What... spending time with the family on Christmas Eve instead of TESTING? :mrgreen:

Of course :D , I get out of my office 2 minutes, go kiss my wife and check things around the house, then run back to my office for another 2 hours ( She's having a good time with the kids anyway :wink: ) :mrgreen:
Quote:


Quote:

Originally Posted by kwag
Oh boy, they don't speak, they SCREAM :!:

heheh yes it's pretty persuasive. I'm currently testing 528x480, and then will try with different (more sedate) source material.
I want to see those screenshots too :wink:

-kwag

SansGrip 12-24-2002 08:05 PM

Quote:

Originally Posted by kwag
( She's having a good time with the kids anyway :wink: )

Mine're watching Lilo & Stitch right now. They were allowed to open one present tonight and that's what they chose -- it's a Disney movie so it's giving the new receiver a good workout :D.

Quote:

I want to see those screenshots too :wink:
I decided I would test 352x480 again as well, just to make sure I did it correctly last time...


All times are GMT -5. The time now is 09:00 AM  —  vBulletin © Jelsoft Enterprises Ltd

Site design, images and content © 2002-2024 The Digital FAQ, www.digitalFAQ.com
Forum Software by vBulletin · Copyright © 2024 Jelsoft Enterprises Ltd.