Importing VOBs on a Mac

[Reading Bug]

Hi all,

I asked this question on the forum last fall but, since finally beginning my project, have come across a slew of variables and feel a new thread would be appropriate. I’m pretty new to video editing and am trying to accomplish a relatively ambitious task: I want to fix the audio stream of a DVD littered with impulse noises, but without losing any of the picture to conversion or frame-dropping during import. I already have the software to clean the audio (Izotope RX) and now I want to:

1) put my DVD content directly on my Mac’s hard disk with no picture loss

2) edit the material into separate files, before or after import, so each file can be its own title on the new DVD

3) demux the audio, repair it, remux it back

4) burn it back to DVD

I understand from my previous thread there are apps that will do DVD-to-HDD (ie: DVD Decrypter) but these seem to be mostly for Windows. What about Mac?

I’ve tried MPEG Streamclip but wasn’t happy with the quality of DV (which is why I want to import VOBs directly to avoid loss). I know I will lose something when it goes back to DVD, but I want to avoid all opportunities to degrade the image before that final step.

I also don’t want to lose any frames at breaks in the program stream (which happens with Streamclip). I’m looking at Avidemux now and it appears the same will happen – it skips the final frame at the end marker. The original material was videotaped and even one dropped frame is quite noticeable. Can’t DVDs be imported seamlessly?

Another problem is that Izotope RX will only extract audio from mov, avi, mpg, dv, m4v, and wmv. Of course, I don’t want to convert because I’ll lose image quality. However, it will also handle audio in wav, aiff, mp3 and Quicktime audio (m4a, m4b, aac), so if an app can demux the audio stream to one of those formats and then remux after the repair job, that would be great. Avidemux seemed to create an valid mpg file during my test, but it had no audio and RX wouldn't extract it.

Here’s their website: http://izotope.com/products/audio/rx

Thanks in advance!

[guns1inger]

If this is a non-protected (i.e. non-commercial disc) then all you need to do is drag the video_ts folder onto your HDD. If it is protected then you need mactheripper.

Unfortunately, after that the recommendations always seem to be to convert the file to another format because the majority of tools for the mac support a very limited number of formats. On a PC you could easily use VOB2MPG to extract the video and audio and an mpeg programme stream and go from there.

[Reading Bug]

Not that it helps me, but does using VOB2MPG result in a lossless file? It seems to be a tool to convert, just as you would to DV or AVI...

[lordsmurf]

You can always install Windows XP inside OS X, using Parallels or VMWare Fusion.

[guns1inger]

VON2MPG extracts the video and audio from the VOB and puts in an MPG container. It is lossless in so far as it does not re-encode, so the video and audio data is identical to the source.

[Reading Bug]

Thanks guys, those suggestions sound great. I'll try running Windows on my Mac and using VOB2MPG. I'll let you know how it goes.

Do you have any suggestions, for Win or Mac, for editing the mpg and remuxing the sound after my repair job? Izotope RX can demux only, and I'm not even sure what format it will save in after that.

I'd also like to try burning without reencoding now. It sounds like SVCD2DVD will do that - what are your experiences with that app?

[guns1inger]

I use Izotope, but as a plugin to Sound Forge/Vegas. It is brilliant application for what it does. I would probably demux with DGIndex, work on the audio in Sound Forge, then remux with AVIDemux, keeping both the video and audio in Copy mode.

I would then use Womble Mpeg VCR to split the file into titles, demuxing the output to elementary streams ready for authoring.

[lordsmurf]

I still use TMPGEnc Plus 2.5 to demux and remux one by one.
I use BatchDemux to demux a bunch of videos at once.

I believe MPEG Streamclip will demux/remux on Mac, but it's been a year since I last needed to demux/remux on a Mac.

[Reading Bug]

Ok, so I convinced my roommate to let me try VOB2MPG on her Vista laptop, since I don’t have Windows on a Mac yet. I think I might go with Fusion over Parallels, btw. Any opinions?

I’m really happy with VOB2MPG – excellent transfer to mpg and no frame dropping. I can see the difference just watching it on Windows Media Player. Smooth, fluid, looks just like the original DVD.

I looked into MPEG-VCR, then saw MPEG Video Wizard, which looks better equipped to handle the frame-by-frame editing I want to do. It seems I can edit without reencoding afterwards (like MPEG-VCR), but are there any limitations? I can cut, copy, paste (even video from another mpg file?) and then just click save when I’m finished? Even if the resulting file becomes larger? Here’s what their website says:

The Womble MPEG Video Wizard contains all of the key features of its predecessor, Womble MPEG-VCR: frame accurate editing, fastest scrubbing of any MPEG editor, fastest frame stepping, and no re-encoding when editing DVD-compliant MPEG captures from the latest hardware boxes.

http://womble.com/products/mvw.html

If I indeed check out ok, then I'll aim to use Sony DVD Architect (which I’m glad I accidently purchased) to write the stand-alone file. Their literature says:

To ensure that your DVD preparation and burning process goes smoothly, you should attempt to save your media files in the supported formats prior to bringing them into your DVD Architect project… the following files will not require recompression if encoded with proper parameters:

AC-3 audio (.ac3)
PCM audio (.wav)
NTSC MPEG video (.m2p, .mp2, .mpg, .mpeg)
PAL MPEG video (.m2p, .mp2, .mpg, .mpeg)

Note: The Sony Creative Software Inc. Dolby Digital AC-3 Studio and MainConcept™ MPEG-2 encoders provide templates that, if used without any modifications, result in files that do not require any recompression (unless the file size is too large to fit on a DVD).

Will my "modified" mpg remain fit to burn to DVD, without the need to reencode for authoring in Architect?

[tomlee59]

In a word, yes. You have produced a DVD-compliant MPEG stream, so it needs no re-encoding. (For details on what is compliant, take a look at "What is DVD" in the upper left-hand corner of this page). Author, burn and enjoy.

[Reading Bug]

Ok, so I'm good for Architect? What about editing the mpg with MPEG Video Wizard? Can I alter its properties any way I choose (even the file size) and it will maintain its compliancy?

[tomlee59]

You really want to read "What is DVD", believe it or not.

But the short answer is: File size just has to be small enough to fit on the target disc; only a few resolutions and framerates are allowed; peak bitrate should not go above, say, 9000kb/s; and audio should be in ac3 to guarantee compatibility, but mp2 will almost always work, too (mp2 compatibility is not required in the US, but it is in Europe; I have yet to encounter a US DVD player that won't work with mp2).

Be advised that editing MPEG2 can force re-encoding, depending on the tool, and where the edits are. Simple splices/cuts at I-frame boundaries are relatively benign. Anything else can have a wide-ranging ripple effect.

[Reading Bug]

Thanks tomlee59, I had read that before but read it again anyway. I do understand a little better, but not enough to judge my situation. Here’s where I am so far. If you (or anyone) know of a better or simpler way, please let me know.

The source DVDs are shows taped off tv - six episodes per disc. My test run of VOB2MPG took all six half-hour episodes and saved them as one, 2½ hour mpg (7.36 GB). Like it should right? I want to split them up into individual episodes again and save them each as new mpgs without reencoding.

Then I want to go into each one and insert new intros and outros, as they all have rough spots on the opening theme and closing title cards (another disc has footage of clean openings and closings). I want to cut out the damaged opening and replace it with the clean one: roughly one minute of video. Then do the same with the closing cards: roughly ten seconds. Would you say these alterations, if done using MPEG Video Wizard, are small enough to be “simple” splices? I'm not sure if I-frames relate to the above procedure.

Once the video editing is done, I'll need to fix each new mpg's full audio track in RX. However since RX won’t handle AC-3 or MP2 (and the video edit will probably create a jump anyway), I’ll likely need to record the audio separately as PCM/wav, then clean it and sync it up as a separate track in Video Wizard, without affecting the picture. This seems feasible:

http://www.womble.com/support/FAQ11.html

I know every situation is different, but I'm really looking to get the best idea of what to expect before I shell out for more software, including Fusion and XP.

[lordsmurf]

MPEG Video Wizard, yes.
Not MPEG-VCR, it can have issues with splicing in and out, it's best for cutting only.

MPEG Video Wizard for audio track, sure. I do it a lot. Clean up the audio in SoundForge and/or Goldwave.

[Reading Bug]

Thanks Lordsmurf, but I just edited my post for clarity. Would you mind checking my rewrite and verifying I'm good?

[tomlee59]

Yes, what you are proposing to do can be accomplished as simple splices. If you do so, then changes can be localized to the GOPs that comprise the splice; the rest of the video should remain untouched.

The only real work you'll have to do is syncing up the audio after modification. First convert to .wav (which is a universally editable format); I use Audacity for this, but use whatever tool you're comfortable with.

Once you have an editable audio track, you're halfway home. Make your edits, re-integrate with your video, author, then burn your dual-layer disc. Use only T-Y or Verbatim, and select the layer change to occur at an innocuous location (e.g., at a scene break or between titles). You should be good to go.

[Reading Bug]

Thanks Tomlee. Using a DLD is only if I want to put them all back on a single DVD, right? I might do custom compilations with just two or three episodes...

[lordsmurf]

You can convert the AC3/MP2 out to WAV using BeLight (freeware).

[Reading Bug]

Cool, I'll look at that.