How to get AVI out of VOB for editing with VDub?

[df7nw01]

Hello.

I got the "The Art Of War"-DVD which has the "21st Century Fox"-Intro in 1.85:1 and the movie itself in 2.35:1. So I want to cut the 1.85-intro and replace it by another "21st Century Fox"-Intro which I got in 2.35:1.
So how can I do this? How can I get a video out of the VOB to cut the intro with VirtualDub and encode it after that?


Stefan

[jggimi]

I'm not sure what processes you are using prior to vdub; also, I'm not familiar with that dvd. So this may or may not be what you're looking for:[list=1] I would tend to think, since these two sequences are in different aspect ratio, that these may be in separate program chains. If that's the case, you might try using SmartRipper in Movie mode to extract the .vob files. "Movie" mode will automatically select Angle 1 of the largest program chain. You may then select alternative program chains, and/or select by chapter/cell. If your need is to assemble cells from different program chains as a .vob or .vob sequence on HD, I believe that Vstrip is flexible enough for that purpose.be the most capable tool. If you have multiple .vobs that you wish to combine, dvd2avi can do this easily, just by adding additional vobs to the input stream. This tool can produce .avi output, but I would think most use it to produce .d2v output instead. These are used as input to AviSynth preceeding an encoding in Vdub -- this is the procedure used by Gordian Knot for DivX encoding, for example.[/list=1]

[df7nw01]

The two scenes in different AR are in the same cell, same chain, I also had that idea :(
I usually encode them using M2A and after that, I mux the audio (AC3) to the video with AviMux, so I am not familiar with VDub oder D2A...
And what do I have to select to get an uncompressed AVI?

[N_F]

You could try first encoding the movie separately (cut away the intro) and then encoding the intro with the right AR. As long as you use the same resolution you should be able to join these two later. It may take some work, but it's the only way I can think of.

[df7nw01]

Hello.

I could open the completed DivX (including the incorect intro) in VDub and cut the intro.
But I don't get it to save it compressed again. How can I do save it after editing. And a general question: if I open a compressed file, edit it and save it again in the same compressed format as before (e. g. DivX), is the quality then equal to the original video or is it less, because something compressed is compressed again?


Thanks

Stefan

[Belgabor]

Originally posted by df7nw01

But I don't get it to save it compressed again. How can I do save it after editing. And a general question: if I open a compressed file, edit it and save it again in the same compressed format as before (e. g. DivX), is the quality then equal to the original video or is it less, because something compressed is compressed again?


Only if you choose 'direct stream copy', otherwise the video is reencoded which leads to quality loss.

On the other hand why dont you use a simple avisynth script, eg

a = MPEG2Source("movie.d2v").Trim([movie part without intro in wrong AR])
b = MPEG2Source("intro.d2v").Trim([Intro in right AR])
a ++ b
[Resize]


Cheers
Belgabor

[jggimi]

And what do I have to select to get an uncompressed AVI? File...Save as AVII could open the completed DivX (including the incorect intro) in VDub and cut the intro.
But I don't get it to save it compressed again. How can I do save it after editing.Video....Compression, then Select DivX (Pro) Codec, then configure, then File....Save as AVI.And a general question: if I open a compressed file, edit it and save it again in the same compressed format as before (e. g. DivX), is the quality then equal to the original video or is it less, because something compressed is compressed again? The quality will be MUCH worse.

You are better off setting Video....Direct Stream Copy, and not attempting to re-encode it, as DJ Bobo recommended.

If you wish to cut away sections of your content, you must take sound into consideration. My recommendation: Do your splitting of an already muxed .avi file. Use Nandub rather than VirtualDub. Nandub is a variant of Virtual Dub, but it supports many more sound formats than Vdub, though only the DivX 3 video codec. It is most often used for splitting and joining .avi and muxing audio, using Video....Direct Stream Copy. I recommend it because Doom9 has a guide. Click on this link (http://www.doom9.org/virtualdub_procedures.htm), and then search for the keyword "splitting".

Good luck.

[df7nw01]

Hello.

That would be working like this, but of course, it's not as easy as that. The scene ends between two keyframes... I don't think there is any way getting it split nevertheless, is it?
So what is the difference between frames and keyframes and is there any way to make a frame been handled as a keyframe?


Stefan

[jggimi]

Keyframes are frames that contain complete image information. All other frames contain only partial information. Here's a link (http://forum.doom9.org/showthread.php?s=&threadid=19436) to more information.

When using "Direct Stream Copy" Vdub will not do re-encoding, so all cuts must be made at keyframe boundaries -- You want to make cuts at other points, which would involve re-encoding.

You may be better off assembling your "cuts" in dvd2avi, or through using AviSynth filters such as Trim().

[df7nw01]

"You may be better off assembling your "cuts" in dvd2avi, or through using AviSynth filters such as Trim()."

First, thanks for your answer. But as I'm not familiar with the two mentioned programs, could anyone perhaps tell me what to do or give me a link to a guide?


Thanks

Stefan

[jggimi]

DVD2AVI is a program that has several purposes. Based on it's name, it can be used to extract video and audio streams from .vob files, and then encode .avi files as a result. But a much more common use of the program is to "frameserve" the video stream from a set of .vob files into other programs. A third use is to extract audio streams.

Trim() is a command used in AviSynth. AviSynth, quite simply, is a tool that allows you to manipulate video -- cropping, resizing, and other video filtering -- with commands in a text file called a .avs file, and then use that text file as if it were an .avi file in any program that reads .avi files, including media players and virtual dub.

Together, DVD2AVI frameserving with AviSynth are integral components of several encoding suites, including both DVD2SVCD, used to create video CDs in several formats, and Gordian Knot, used to create .avi files from dvd using the extremely popular DivX codecs.

Here's Doom9's guide (http://www.doom9.org/mpg/d2a-mpeg2dec.htm) on AviSynth frameserving, but due to wide use of these tools, you'll find many of Doom9's guides include operating DVD2AVI, AviSynth files, or both. There are also both DVD2AVI and AviSynth forum sections here, with FAQs and Sticky threads.