Horrible Undersize problem

[SoaD]

Hi all,
I've ben using GKnot for not a very long time, and my experience in encoding is limited.
However, I was hoping you will be so kind to answer my qustions.
So here goes:
I was trying to Rip "Rage Against The Machine - The Battle Of Mexico City". (R0, 1H-1M-33S, NTSC, Interlaced, 4:3, 29.97FPS) it's a live concert and only an hour long so i decided to Rip it as a 1CD with AC3 (448 Kbps).
The concert itself is 16:9 but it says 4:3 cause some of the chapters are documentarys from mexico and they are 4:3.
In DVD2AVi i chose Field Operation->None and after opening the d2v file in GKnot i switched the FPS to 23.976.
I chose a resolution of 512X288 after the DivX 3 compressibility test I got sucky values; 0.32 Bits/(Pixel*Frames) and 34.4 in the compressibility test. playing with the resolution didn't help, i would get crappy quality if i used a higher res and wouldn't reach my desired file size for a higher Bits/(Pixel*Frames) value (which what eventually happned).
I picked the Neutral Bicubic resize filter, do I need to use the Sharp Bicubic one?
the final file size was 614MB ot of 700, from that the sound was 197.
Do you need the GKnot log?

Thx in advance :)

[FFiXx]

Use antishit 16:28:50 or lil lower

[DagMan]

Why do you set "Force Film" to "none", because if "Framerate" is 29.970 (NTSC) and "Video Type" is FILM at a
percentage higher or equal to 95% you have to check "ForceFilm".

Perhaps it helps.


DagMan

[manono]

Hi-

I think he said it's 100% NTSC-no film in it at all maybe.

What I want to know is, if he made the .d2v with no Field Operation and 29.97fps, why did he then change the fps in GKnot to 23.976fps? Did he try to IVTC a pure video stream or something? If you have a pure interlaced video source (and you haven't given us quite enough information yet to be sure, although most of those concert DVDs are), then you should keep it at 29.97fps. otherwise it becomes jerky (although with the Rage boys jumping up and down, you may not be able to tell).

You have more serious problems than just trying to figure out whether to use Neutral Bicubic or Sharp bicubic. Try reading this (http://forum.doom9.org/showthread.php?s=&threadid=23776) and this (http://www.doom9.org/aspectratios.htm) to help get an idea of what's going on.

[SoaD]

I apologize for the lack of information, as I said, I'm a noob so I didn't know which data was needed and which was irrelevant.

i belive it's a pure NTSC, pure Interlaceds source, I've recently read in a few threads here that i sholdn't change the FPS value to 23.976.
Iv'e also chosen Smart Deinterlace and not IVTC.

Any more information? I will be happy to answer.

Once again, Thanks in advance.

[manono]

Hi-

First you have to confirm that it's a pure interlace source or just the result of a bad telecine job. That first link I gave you can help you determine that (it probably is interlaced all the way though). Pay special attention to hakko504's last post in the thread. Yes, I know the thread is hard to understand, but it's important stuff to know if you're serious about this. That is, are all the frames interlaced? If so, you keep it at 29.97fps and just deinterlace it (as you said you are doing). I'm not positive, but when you changed it to 23.976fps in GKnot, that's what probably made it undersized. My guess is the GKnot log had something to say about that.

Second:

The concert itself is 16:9 but it says 4:3 cause some of the chapters are documentarys from mexico and they are 4:3.

No, it says 4:3 because the DVD AR or DAR(Display Aspect Ratio) is 4:3. That is, it's all 4:3, both the letterboxed wide screen as well as the full screen portions. The second link will explain that one. Pay special attention to the paragraph about 2/3 of the way down beginning:

There are also DVDs which have a DAR of 4:3 but contain widescreen picture.

And Third-just because it's only an hour long doesn't by itself mean it's easy to do for 1 CD with good quality. The results of your compressibility test prove that with the borderline resolution you were forced to choose. You might consider making the audio MP3 in order to free up 100 MB or so for the video.

Good luck and Welcome to the Forums.

[SoaD]

One way of finding which is wich is first using DVD2AVI to approximately find the NTSC parts of the film. Then use look at the following .avs in VirtualDub
What AVS file? and where in VDub can i get the information?

You might consider making the audio MP3 in order to free up 100 MB or so for the video
Do you think lowering the bitrate of the ac3 can significantly reduce the audio size? or does i have to risk hurting Zack-De-La Rocha's screams in order to get good video?
I think it's important to say that even the DVD isn't in really good quality in comparison to other DVD's I've seen.

Also, I forgot to mention that I ripped the VOB's without the documentaries so I can crop it to the correct AR. was that a good move?

[jggimi]

What AVS file?Either edit the .avs file that Gknot created, or build the 4 line script that Hakko showed as an example immediately below the text you just quoted. If you do the latter, don't forget to add the appropriate directory structure to point to the files.... see any of your Gknot .avs scripts.and where in VDub can i get the information?Huh? Just examine your content, frame by frame, grabbing the slider with your mouse to get to a scene, then the right and left arrows on your keyboard, to see how individual frames look.Do you think lowering the bitrate of the ac3 can significantly reduce the audio size?You can check the size impact of different mp3 bitrates, just put different bitrates into Gknot's "Audio A" calculater, and the estimated file size will appear.

[manono]

Hi-

Just to add my 2 cents again. Maybe the easiest way to see what's on the DVD is to open up that 29.97fps .d2v you made in DVD2AVI in GKnot and find a part with lots of movement (that shouldn't be hard) and advance frame by frame. I'm guessing every frame will be interlaced. You should do this in several places to make sure it's not a hybrid (a mix of pure interlace and film). So if it's all interlaced, then you just deinterlace.

As for the sound, I don't use AC3, so I can't answer the question about lowering the bit rate. However, by using the AC3 track, you pretty much commit yourself to making a 2 CD rip if you want the video to look at all decent. If you want to keep it to 1 CD, I'd suggest making a high quality MP3 rip. You can even do it for surround sound if you like. You'd need a very high quality sound system and very good ears to tell the difference between the AC3 and MP3 done to Alt Fast Standard or higher quality. Zack's screams will come through loud and clear. You can check this out by doing it and playing back the sound to hear if it's high enough quality for you.

As for leaving off the documentaries-you would have had correct AR in any case (assuming you do the cropping and resizing with GKnot), although the full screen documentaries would have been heavily cropped to get them to 512x288. But if all you wanted was the concert itself, then why not? I just hope you don't wind up with audio synch issues as a result of cutting out chapters. But it should be OK.

[SoaD]

Thank you guys for all your help.
This is a really great forum (and a really great program).
I will come back with how the process went and the result.