Difference between VOB & MPEG files

cottage · #1 (**permalink**) 01-06-2009, 04:38 PM

Occasionally I've struggled in my attempts to edit VOB files. Normally, I've simply changed the file extension from VOB to MPG and edited the file and it has worked well. However, once in a while I find a VOB file that won't cooperate. The problem files seem erratic. The problem VOB can take a long time to load, freeze the editing application, or apparently contain snippets of video that actually reside in other VOB files on the DVD.

I've done a lot of searching regarding the difference between VOB & MPEG files and it seems that the VOB contains "file offsets and time duration of all chapters" that the MPEG file doesn't include. I won't claim to fully understand the difference. However, I've been looking for a program that will convert VOB files to true MPEG files (without all this extra data) and will do so without re-encoding. I've seen and tried a few programs that have been recommended in other posts (MPEG2Cut, DVD Decrypter, YASA VOB to MPEG Converter and others). The programs that I have tried either freeze when some VOB files are loaded or they split VOB files into smaller VOB files or they re-encode the VOB and reduce the video quality. Some will only convert the VOB file to lower quality SVCD formats.

Therefore, can anyone recommend a good program that will convert VOB files to true MPEG files and leave the frame rate the same as the original (i.e. will not re-encode). I'd prefer freeware but am willing to pay for a good program that works.

Thank-you in advance

Mark W · #2 (**permalink**) 01-06-2009, 10:13 PM

I would be very suprised if there is anything out there that can produce unbuggy files without re encoding.

VOBs were never deisgned to be editable and editors are not deisgned to edit them.

Z Cheema · #3 (**permalink**) 01-06-2009, 10:26 PM

Sony Vegas can import a DVD onto the timeline as an MPEG, with audio to edit the file.

if you can find out the original encoding (there are programs that will do that) then when you render back out if you use the same parameters as the original there will be no re-render of the file.

cottage · #4 (**permalink**) 01-08-2009, 12:03 PM

Mark W....
Thank-you. I can't say that I'm surprised by your answer. I've tried many programs with my "buggy" VOB files and have found nothing that works.

Z Cheema....
Thank-you too. Vegas is one of the editing programs that I use. Most of my original VOB files have been recorded on a DVR. They are recorded using VBR with a maximum bit rate of 9496. Unless I'm really stupid (which is possible), I can't see how to set the Vegas project properties to VBR.

Thank-you for the answers. It looks like I'll continue to struggle the same way that I have in the past.

Z Cheema · #5 (**permalink**) 01-08-2009, 04:06 PM

The VBR is not in the Vegas project settings, it is in the render template when you go to render, select custom and you can make the selection there.

I have mine own made up to allow for different amount of times on to a DVD.

Good luck

lancecarr · #6 (**permalink**) 01-09-2009, 01:29 PM

A VOB file is not a video file per se. It is a container file that adds extra information to the MPEG2 files within the container. The reason for this is part of the DVD standard. If you look at the files within a DVD you will also find ifo and bup files.

The ifo files (InFOrmation) and bup (BackUp) tell the device reading the DVD where everything is, where to find it and what the device should do. Part of these instructions involve the data of the VOB files hence the file offset data and the time code data.

MPEG2 files are just video. Most editing software, when you import from either the DVD itself or VOB files you have, read through the vob file and simply extract the underlying MPEG2s. This function is described variously in many editing programs but it is usually something like "Import from DVD."

Vegas will do it and so will Pinnacle Studio, VideoStudio, NeroVision (contained within the Nero 9 suite) and Roxio Creator 2009. All without loss of quality as it is a straight copying process.

MovieMaker will not do it because it has no inbuilt MPEG2 codec and this is the reason many of the free solutions wont work.

cottage · #7 (**permalink**) 01-19-2009, 08:58 PM

Thank-you lancecarr,

I finally got around to experimenting with Vegas and it works like a charm. I used the "File/Import/DVD Camcorder Disc" command and Vegas imported everything, converted it to MPEG and separated it by chapter.

However, this only seems to work when importing directly from a DVD. I tried to import only a VOB file stored on the hard drive and Vegas couldn't see it. I then tried the "Import Media" command but apparently it only imported but did not convert the VOB file. Therefore, I assume that Vegas needs the IFO file to know what to remove from the VOB file.

Do you know if there is any way to use Vegas to convert a VOB file that is orphaned from it's IFO file?

lancecarr · #8 (**permalink**) 01-20-2009, 07:46 AM

Hmmm... it sounds like Vegas has been programmed to only expect a vob structure when importing from a disc. When you try to do it from a file on the computer it may just get confused! A bit silly really, I know a number of other programs that have no problem with it.

You could try a program called "Super." It is free and may be able to convert it for you.

Do you have any other software on your computer that may be able to do it? Off the top of my head I am thinking, Nero, Roxio Media Creator or any other suite that came with the DVD rom?

Z Cheema · #9 (**permalink**) 01-20-2009, 03:02 PM

record the VOB on a RW DVD and capture that way, may work....

cottage · #10 (**permalink**) 01-20-2009, 04:41 PM

Originally Posted by lancecarr

Hmmm... it sounds like Vegas has been programmed to only expect a vob structure when importing from a disc. When you try to do it from a file on the computer it may just get confused! A bit silly really, I know a number of other programs that have no problem with it.

You could try a program called "Super." It is free and may be able to convert it for you.

Do you have any other software on your computer that may be able to do it? Off the top of my head I am thinking, Nero, Roxio Media Creator or any other suite that came with the DVD rom?

Thanks again lancecarr,
I have the program Super but it will re-encode the files that I am working with. Most files come from my DVD recorder and are encoded in VBR max bit rate 9496. Super doesn't give me that option.

I also have Nero version 6 and, as per your suggestion, tried NeroVision. It seems to convert the orphaned VOB file on my hard drive to MPG format. However, it is not as slick as Vegas.

I am quite happy with the method that these two programs provide.

Therefore, my problem is solved!

Thank-you again,
Cheers,
dss_cottage