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View Full Version : Menu VOB to MPEG-2 Conversion


lifeson99
25th June 2006, 18:44
In DVD Lab, I created a full DVD with 1 Root Menu and 3 sub-menus. I added transitions where the menu "burns away" and you see the next menu underneath. DVD Lab creates a separate video clip whose 1st frame is the beginning menu and last frame is the menu you are going to, and the DVD simply plays that clip. Very cool. I even added an audio clip of fire burning to the transitions.

Removing Audio directly from a VOB ??

But I and did not like fire sound, which quickly becomes annoying. DVD Lab has a drawback in that you cannot just make a small change, such as remove audio from a menu transition and then re-compile just that VOB. It insists on redoing the whole damn thing, which takes a half hour in this case (this DVD has about 60 video clips on it).

The Menus VOB for the first VTS set on a DVD is always named "VTS_01_0.VOB". Since I only wanted to change that VOB and was not changing the duration and did not need to re-order anything or change any IFO block references - I tried a shortcut - converting the VOB to MPEG-2, removing the audio, and converting it back to VOB.

The result is that for my tools at least, this is impossible. If anyone know how to do that without re-authoring the whole thing - please let me know.

Menu VOB" file to MPEG-2 Conversion

In trying to remove the audio, I did find some very interesting things about conversion of the "Menu VOB" file to MPEG-2 . . . it is very different than coversion of the movie VOB's. Here are a few of the utilitites I tried to work with:


Video Redo converts VOB to MPEG-2 without re-encoding so it did it in a few seconds. However, the result was messed up - it yielded a 5-sec clip, whereas the original VOB is 15 secs. So Video Redo works fine with the movie VOB files but not the menu VOB.

TMPGenc failed and only showed a single frame in the MPEG-2, although the audio played normally.

Ultra Video failed, and actually moved segments around - rearranging the order !!!


*** only Womble MPEG Video Wizard worked, and it worked perfectly (almost). The only difference was that the converted file's duration (13:26) was a couple of seconds less than the original VOB (15:08). I have to explain the makeup of this VOB to tell you why. I used the burning transition to go from the Root to each sub menu and I used a simple sliding transition to go back to the Root menu. The VOB has the following content in this order, which all of it plays sequentially:

4 still frames of the Root Menu, submenu-1, sub-meu-2, and submenu-2
the 3 transition video clip of the Root menu "burning" to each of the 3 submenus - they play sequentially
the 3 transition video clips of each submenu sliding over to reveal the Root menu


The oddity is this - the first 4 "still menu" frames in the VOB, as I single-stepped through the I-frames, the timing for those first 4 stills is spaced apart by 1/2 sec:
00:00, 00:15, 1:00, 1:15
Then first video clip, which is the first Root menu to Submenu-1 burning transition video, begins playing at 2:00 and the steps at that point are normal. They are sequentially timed at 30 fps:
2:00, 2:01, 2:02, etc.

The Womble converted MPEG-2 placed the first 4 menu stills into successive I-frames timed at 30 fps at:
0:00, 0:01, 0:02, 0:03
Then the rest is the same as the VOB, with first video playing at 30 fps:
0:04, 0:05, 0:06, 0:07, etc

I am not sure why the menu stills are placed 1/2 sec apart in the VOB. Perhaps that is a DVD structure standard so that the player can identify them as Menus, and NOT videos.

Womble - the Good and the Bad

I really love Womble. It was the only converter that worked for menu VOB's, and in fact, only Womble allowed me the flexibility to step through either the I-frames, or the P-frames, or through all frames. Only Womble played the menu VOB smoothly. Only Womble can scrub through MPEG-2 files timeline quickly and smoothly.

HOWEVER - it makes terrible converted MPEG's !!! I have tested it extensively, and in all cases the MPEG conversions have a really bad case of "the jaggies" on the edges, especially with smaller sized clips such as MPEG-1 SIF at 352x240.

I have gotten the BEST results for quality of these video conversion using TMPGenc Express 3.0, which is actually the only converter that has almost no "bugs" that I could find.

Super-Compressed DVD's

As a side note that you may be interested in . . . check out my website (InfoCellar.com (http://www.infocellar.com/DVD/super-compressed-DVD.htm)). It has the full rundown of all the utilities (the good and bad) that I have been working with - and a method that I have been using to create Super-compressed DVD's (5 1/2 hours video on one DVD-5).

As to the super-compressed DVD's, it is amazing how good the videos actually look on my big-screen TV, considering they are MPEG-1 files. Try making a short sample and see for yourself !! The trick is using very high quality MPEG-1 at much higher data rates than most MPEG-1 files. I used high quality source video and used the highest "legal" MPEG-1 data rate for the target video - which according to TMPGenc is 1856 kbps. I set the video to 1602 kbps, the audio to 224 kbps, and that leaves enough room for the 30 kbps mpeg-1 control bits. The data rate is about 1/4th that if a standard DVD, but about 3 times that of a standard desktop video clip. So this is a "happy medium" between compression and quality. I compressed all 3 DVD's from the 1st Season of "Scare Tactics" plus 8 clips from the 2nd Season onto one DVD, for a total of 3.96 GB - so I still have a ton of room leftover !!!