Is it possible to convert VOB files to AVI files?

[Sulli]

Hello, I have been given a hard drive which has many movies which i would like to convert to AVI. Each movie typically has two folders, one being AUDIO_TS & VIDEO_TS. For some reason every AUDIO_TS file is empty. The VIDEO_TS folder has a number of files one always being VTS_01_0.IFO plus 4 or 5 VOB files such as VTS_ 01_1.VOB. If its possible to convert them to AVI files i would like instructions how to achieve this. I already have Virtualdub installed as well as Freemake if it can be done with those programs. Of course im willing to download other programs if its a simpler solution.

Thanks in advance

Sulli

[Baldrick]

Use a dvd to avi divx/xvid converter like the old good autogk or fairuse wizard or xvid4psp. Open the video_ts folder or the vts_01_1.ifo.

[jman98]

Hello, I have been given a hard drive which has many movies which i would like to convert to AVI. Each movie typically has two folders, one being AUDIO_TS & VIDEO_TS. For some reason every AUDIO_TS file is empty.

This is normal. When DVD format was finalized, AUDIO_TS was created to be used by a future audio format that would use DVD discs. Eventually that format became DVD-Audio. So it's normal for DVD video to have an empty AUDIO_TS folder.

[Baldrick]

You could also convert to a single mpg with vob2mpg. No reconversion. If you for example are trying to edit the video in some application that doesn't support dvd vobs directly.

[sanlyn]

VTS_01_1.vob, VTS_01_2.vob, etc., make up the video + audio of the DVD movie. The other files are menus and other features. The movie is in the VOB's, which are really MPEG2 files configured for DVD playback. An app such as VOB2MPG joins the files into a single MPEG2. To convert them to AVI, you can use DGIndex, which is a component of the free DGMPGDec package.

To avoid quality loss you can convert from mpg to AVI with Avisynth and DGIndex using lossless compression such as Lagarith or lossless h264 (Lagarith is probably more simple to use). A 90-minute movie with Lagarith lossless compression would be about 35GB. You can make smaller files with something like DivX, but expect a quality loss. For archival purposes, keep the original DVD folders (burn to DVD). There are multiple ways to go from MPG to AVI. It depends on what you want to do with the AVI.

[Sulli]

Thanks all for your replies. Ive had success in converting the VOB files to AVI files. I have one further question however. The VOB files were about 4.5g and the converted AVI ended up being one third the size at 1.5g. So is the smaller AVI file actually of inferior quality? I understand converting CDs to mp3 gives you an inferior product which is of no consequence when listening through earbuds on an mp3 player; only if you play them though a quality hi-fi system will the audiio loss become apparent. Doess the VOB to AVI conversion have the same result as the CD to mp3 conversion?

cheers

Sulli

[sanlyn]

"Converted to AVI" could meqan many things. You mean you recompressed with lossy compression, such as DivX, etc.? Going from lossy compressed VOB to even higher levels of lossy compression in an AVI cointainer is definitley a quality loss. But you don't say what kind of compression you used for the AVI.

[Noahtuck]

Yes, unless you use a lossless format.

If something goes from 4.5gb to 1.5gb its pretty obvious something was lost.......

[Sulli]

Hello Sanlyn

Im not sure what kind of compression i used but ill explain what i did. I used the program DVDfab version 8.1.3.8. The program asked me to "please choose video file/folder" so i loader the movie folder and it loaded the 5 VOB files. I then chose from the format list( i.e AVI, MKV, MP4 etc etc) the AVI selection. From there it was as simple as hitting the "start" button and the prgram did the conversion without any problem. My initial DVD folder of 4.20g was converted to an AVI file of 1.76g. I know to expect a smaller file size - thas part of the attraction - but im just wondering what it means in terms of quality loss if any? I know advances in technlogy mean that a six cylinder car can produce as much pwer as a V8 of times gone by so was just wondering if the smaller AVI file i have generated has the same quality as the larger DVD file(s) i began with.

cheers

Sulli

[olyteddy]

Look at them both and judge. VLC or MPC-HC can probably play both types (open the DVD folder or the .IFO file to play the DVD version) and using 2 instances of the player you can judge if the decrease in quality is acceptable to you. Action scenes and scenes with great detail will show the result the best.

[Noahtuck]

just wondering if the smaller AVI file i have generated has the same quality as the larger DVD file(s) i began with.

What part of NO do you not understand ?

Although I actually said yes but that was in response to you asking,

The VOB files were about 4.5g and the converted AVI ended up being one third the size at 1.5g. So is the smaller AVI file actually of inferior quality?

It does not matter what format or codec you use, it has lost quality!!!
Not to mention DVDFAB does not have the best encoding software around.....

You seem to get the idea with

converting CDs to mp3 gives you an inferior product

yet you think there is a difference with video ?
You will not see a difference if you are watching them on an Ipod or 13" tv, watch it on a large screen HDTV, you will see it dramatically or you are blind!!

Who do I sound/feel like right now ??
LOL!!!


Some people just don't hear what they don't want to hear.....

[Sulli]

Ok Noahtuck I understand (now) that no matter what the format, smaller size will always be inferior to the larger one. Since you seem to be an authority on this subject let me ask yo something else. I embedded some subtitles of about 40kb size into an AVI file of 800mb size and the new embedded subtiled file turned out to be 4.00g.( ive since worked out how to do this and end up with a file of comparable size). So by simply and accidently gaining a file 5 times the size of the original, can i consider that file to be of superior quality? I would have thought you cant make a silk purse from a sow's ear but at the end of the day size is size and surely bigger wins. Perhaps i should just watch it with my own eyes on a HDTV(pleonasm intended!) lol

As to your question i could only guess. Perhaps you sound like someone who doesnt understand there are others out there who really struggle to grasp these concepts that seem to come so easily to you? lol

[Noahtuck]

I embedded some subtitles of about 40kb size into an AVI file of 800mb size and the new embedded subtiled file turned out to be 4.00g

.
So you are saying by simply adding subtitles your file increased from 800mb to 4.00gb ?!?!?!

Then you changed something and it was encoded differently!!
A different format, at a much higher bitrate.....
A 40kb subtitle file does not just magically add over 3 1/2gb's

Authority or not, common sense is common sense......

But you do not say how or with what you embedded these subtitles with.....

So by simply and accidently gaining a file 5 times the size of the original, can i consider that file to be of superior quality?

That's like saying if I take a 4.19mb 128kbps MP3, convert it to a 27.4mb 1141kbps wav file that the wav file is superior quality,
Or taking a 352x288 vcd and converting it to 1920x1080 and burning it to a bluray disc and thinking you have HD video

I would have thought you cant make a silk purse from a sow's ear

Who said you can ??
I said the exact opposite!!

but at the end of the day size is size and surely bigger wins.

WRONG!!!!!!

[Sulli]

Ok Noahtuck theres a lot of technical jargon you've used that i dont really understand the intricacies of but i get the gist. That primarily you cant improve your initial product but can cedtainly diminish it. My intial thoughts were along the lines of that considering we are not comparing apples (VOB) with apples (VOB) but were comparing apples(VOB) with pineapples (AVI) that perhaps an AVI file of 1.7g was somehow comparable to a VOB file of 4.2g. Whilst i fully appreciate this is not the case, for someone from a totally limited technical capabilities( we do exist) i feel its an understandable question.

Your technical explanation leads me to ponder a further question which i wont ask now but goes along are along the lines of, if one is offered a movie in AVI format at 2.gb and also offered another file of the same movie in AVI at 2.gb they may not be of the same quality. For example the first one may have been converted from a VOB file of 2.gb to an AVI file of 2gb therefore no loss. The second file may have arrived at its destination by way of taking a 352x288 vcd and converting it to 1920x1080 and burning it to a bluray disc then converting it to an AVI file of 2gb size. Im guessing by both your technical explanation and you proclamation that size doesnt win, that these two files would not be of equal quality. The question is then how would one determine which is the file that was converted without loss and which was the one that had the convoluted process and is possibly/probably inferior? Feel free to answer that if you wish but they are esentially rhetorical questions.

To specifically answer your question how i embedded the subs and accidently came up wtih a file of much larger size - I used Virtual dub. My subtitles were of SSA format. I went through all the steps one needs to perform this function - i assume you dont need a step by step breakdown - and the step i need to take now to influence the file size is there is a thing called Target Quantizer( I have no idea what this means) which can be set with a numeric between 1 and 31. Before i knew about this function it was probably set to a default and hence gave me a much larger file size. The lower the number the larger the file. So thats how i came to get a larger file by simple embedding subtitles. I figure its best to keep to the original size as ( and no doubt you find a nice way to tell me im wrong) a smaller size will only be diminished quality whilst a larger file wont be improved quality only serving to take up more space on my hard drive.

[sanlyn]

mmm....No. Size alone is not the determinant. You started by saying you have two VOBs of the same size. File type and file size alone do not mean they are the same quality level (I discount the fact that they could be exact copies of each other, but let's assume they are not copies). First, you are making a major error about file types. VOB from a standard DVD video is almost always of MPEG2 format with MPEG2 compression and GOP (Group of Pictures) frame organization. VOB #1 might be a 4GB MPEG2 with a target bitrate of 6500 VBR/8000 max, and is 90 minutes of fast action with a small-size GOP structure to help the fast action. But VOB #2 is also 4GB, a 2-hour video with fast action, a larger GOP of up to 18 frames, and a target bitrate of 4600 VBR/6500 max.

I can tell you right now: the two VOB's are not of the same quality. Both might look "OK" in offhand viewing, but unless VOB #2 has been through some special cleanup and had top-notch expertise in its mastering and compression, VOB #2 will be of at least nominally but visibly lower quality than the other. The first assumption you make is that "compression" is just squishing bits of data together. Sometimes it is (think of a ZIP file), but often it's not (think of MPEG2 and BluRay).

Your second assumption is that "AVI" is a format. It isn't. It's a container (like MKV) that can contain many video formats which could be configured or encoded using many types of compression.

Usually, when a VOB or MPEG2 video is decompressed and converted to be contained in an AVI container, it's frames are decoded from the compressed and partial-picture state into a full-image, uncompressed state in some form of YUV or YUY2 (or YCbCr) colorspace, or maybe even RGB-- which takes up more bytes --. and this AVI container of fully detailed, full-frame images will be expanded from 4GB for a 90 minute video to about 50 or 60 GB of uncompressed AVI. The size of that AVI could be reduced to about 35GB by using lossless compression (Huffyuv or Lagarith, for example, which is almost like squishing data together the way ZIP does it), or to an even smaller container using h264 lossless compression. It's called lossless because...well, because it's lossless, unlike DivX or JPG which discards lots of data according to how small you want your file to be. Lossy compression of that type means that the discarded information is gone -- poof! forever -- and each subsequent re-compression loses more and more data, which is why you don't want to filter and process video in lossy compressed form.

So let's do away with those two assumptions, and start all over.