Nandub bits per pixel calc

[FFiXx]

Hey, I was wondering if sum1 could help to understand how Nandub calc "bits per pixel", Im tryin to get BPP around 0.13-0.18 if that is possible, thx for readin my post :D

These r my settings atm:

VirtualDub.video.SetDepth(24,24);
VirtualDub.video.SetMode(3);
VirtualDub.video.SetFrameRate(0,1);
VirtualDub.video.SetIVTC(0,0,-1,0);
VirtualDub.video.SetRange(0,0);
VirtualDub.video.SetDivX(910,9999);
VirtualDub.video.SetQualityControl(2,16,20,20);
VirtualDub.video.SetMotionDetection(8,15,300,300);
VirtualDub.video.SetCrispness(100,0);
VirtualDub.video.SpaceKF(48);
VirtualDub.video.InternalSCD(100);
VirtualDub.video.SetMinKBPS(350);
VirtualDub.video.SetCurveFile("");
VirtualDub.video.SetCurveMcFactor(0);
VirtualDub.video.SetCurveCompression(15,25,5);
VirtualDub.video.SetCurveFilter(270,6000);
VirtualDub.video.SetCurveCredits(0,350);
VirtualDub.video.SetLumaCorrectionAmp(0,10,30);
VirtualDub.video.SetCurveRedist(0);
// VirtualDub.video.CalcCurveCompression();
VirtualDub.video.SetCompLevelsMain(2,6);
VirtualDub.video.SetCompLevelsA(300,3,16);
VirtualDub.video.SetCompLevelsB(300,4,16);
VirtualDub.video.SetCompLevelsC(300,5,16);
VirtualDub.video.SetCompLevelsD(300,6,16);
VirtualDub.video.SetCompLevelsE(300,7,16);
VirtualDub.video.SetCompLevelK(2,9);
VirtualDub.video.SetBitsReservoir(0,35,30,70,10,0);
VirtualDub.video.SetLowBrCorrection(0,0);
VirtualDub.video.NoAVIOutput(0);
VirtualDub.video.GenStats("",0);
VirtualDub.video.SetEncodingControl("");
VirtualDub.video.filters.Clear();
VirtualDub.subset.Delete();
VirtualDub.brc.Set( 0, 645 );
VirtualDub.brc.Set( 1, 1 );
VirtualDub.brc.Set( 2, 128 );
VirtualDub.brc.Set( 3, 0 );
VirtualDub.brc.Set( 4, 1 );

[manono]

Hi-

I'm not sure if I'm going to answer your question the way you were hoping. But, install Gordian Knot, open the .d2v you made from DVD2AVI, and it tells you the bpp right off the bat. If you're trying to get that figure to help determine the proper resolution and number of CDs to use, then I'd say that bits per pixel is of limited usefullness. A much better way would be to run a compressibility check in GKnot.

On this site you can find both the Gordian Knot software as well as guides on how to use it.

And welcome to the forums.

[FFiXx]

Actually ive read sum of gordian knot from doom9, but what I cant find is a guide which helps u to manually insert keyframe and explains what each of those fields in STATFILE EDITOR really means to the ECF file which is created, but if u could link me to it to show me wrong. Then i must apologies for it.

What I really wonder about Gordian is the field on Stat editor which says SAVE ALL FRAMES with LEVEL 2, Im pretty much newbie with nandub as Im with Gordian so I havnt really figured out what it really does.

And btw im not ripping dvd but im encoding tvrips of SouthPark and sum other which doesnt really need much high motion scenes, thats y I want to know how Bits per pixel works so i can run sum test.

Another thing about frames encoded with diff DRF sizes, I tried setting diff values in Asymetric Compression from 0-90 but sumhow with my settings, the frames r jumping from drf 2-5 drastically. Is there a way to lock it down at drf 2 60-90% without setting the drf size directly as 2 of course. I would really appriciate it if sum1 could help me, thx again.

[manono]

Hi-

Yeah-you're right. Some of that information you have to figure out yourself. Some of it's explained in the Help Tab of GKnot. Some of it's really easy. For example, to reset keyframes, set the Min and Max you want (like 4 and 500 or whatever), push Clear, and then Auto. To make a new keyframe, scroll over to where you want to insert one, and push Manual Toggle.

I've never used that Save all Frames with Level 2 checkmark. I assume it makes the movie with DRF 2, that is Compression Factor or Quant of 2 or at the highest possible quality. You'll lose all control over filesize though.

ECF File-3 types of information are stored. If you redo the keyframes, you'll definitely need to make an ECF. The other information stored is related to the 3 boxes near the top of the Stats File Editor tab- F-Size Correction, Motion Correction, and Luma Correction. If you don't understand them, you can leave them alone with no problem. Personally, I disable the Motion and Luma Correction stuff, and sometimes raise the minimum frame size if I want it higher than 270.

TV Rips, eh? Then you have some more work to do to use GKnot effectively, but I think you can still get bpp from it. Enter length of video, resolution, Audio file size, desired total file size-anything else? Then you should get it.

Not sure I can help you with the problem of DRFs jumping around, since I let GKnot handle it. It might be doing that because you're restricting the DRF range too much for your given file size. That is, if you allowed a wider range (say 2-8) or allowed a larger file size, the DRF change might be more gradual. But I'm just guessing. You want 60-90% at DRF 2, and then the rest should be at 3 maybe? Just make sure your desired file size is large enough to accomodate that.

Anyway-enough for now-play around-experiment-you'll get it.

[FFiXx]

Thx again manono, but there is sumthing i really wondering about letting gordian set key frame or manually set keyframes. Okay then, lets start for what I know. There r 2 kinds of keyframes or maybe even 3, but Im sure there 2. The first one is by inserting a K and the other is a D(high quality Delta frame). And sumhow these frames controls how bitrate are distrobuted, #"%¤%"# Im so lost when it comes to keyframing and nandub options :( help :scared:

[manono]

Hi-

I didn't see a question there. But I think you may be making this harder than it should be. GKnot exists to make the whole process easier. As for Nandub options, it's in the guide. And Koepi has a good "Nandub Options Explained" guide also.

[JasonFly]

Excuse me manno but I don't think that .ecf store luma and motion informations.
I think it just control keyframe insertion
Try to open an .ecf and you will see that it describe only if the frame has to be a keyframe or a normal frame

Tell me if I m wrong

[manono]

Hi JasonFly-

I don't have an ECF handy, so I'm going from memory. When you save the ECF, in the Nandub Files Tab, there are checks for three boxes-Key Frames, Delta Frames, and Motion. If I'm not mistaken, in the ECF itself there's the number from 0-300 which tells you how much motion there is in each frame. But again, I'm going from memory since it's been awhile since I looked at an ECF file. But you're right, the main Luma-Motion information is in the curve and therefore the modified Stats file. Thank you for the correction.

[FFiXx]

Okay i c, I was wondering y gordian made an ecf with numbers. Ive been looking in debug screen alot lately when testing, and I tried changing all the D to K. That was a bad idea but it was only a test so my 3min file became 126mb instead of 30mb in my normal encodings. Ive also used normal manual Key Framing by hand ( adding as @X K ) and my file didnt become oversized.

Okay so i guess gordian controls which frame gets which drf, so any1 know how I can force most of the frame on drf 2 then go slower down to drf3-7 and ends at drf8?

Most of my tests ends up with a drf2:22-28% | drf3:10-12% | drf4:10-12 | drf5:50-65%

Ive only tested with a 3min op from Whistle op (anime) which is really hard to compress :|

[manono]

Hi-

Since you're testing on a small section and can get results quickly, I'd first suggest disabling the Luma and Motion Correction. My guess is that you're getting those big jumps in DRF when some fast action starts. Open up those Customize boxes in the Stats File Editor Tab and push all the Luma sliders to zero, and the Motion slider to 99% and then hit Calculate. That will smooth out the curve a bit. Another thing you can do is in Nandub, go Video-SBC Options-SBC Settings-Compression Levels, and change that top DRF line to Min=2, and Max=5, or whatever you want. I'm not sure what that does to the modified GKnot stats file or to size predictability since I've never done it.

[FFiXx]

Well, I dont fully understand how u insert key frame with Gordian. But u can set direct drf on stats file sumhow I guess. I know ecf file key frame inserting does sumthing as well, or is it just me? heh

Anyways ill try that method u posted and ill paste in the results when i get it, thx.

[FFiXx]

Hmm, nope the result was almost identical to the old one, drf sizes r splitt and it degrades the image qual :scared: bleh, need to find a way to tweak it in nandub i guess :confused: