MTR demux adds picture stutters

[DeadLily]

I used the Demux feature of MTR 2.6 to pull out a single title from a multi-title disk I made in Toast. (There were sound problems in it, so the point was to fix the AC3 track.) I plugged the new AC3 and m2v back into the disk in Toast and rebuilt it. The result was that the chapter had a small picture freeze ever second or so.

I redid the whole procedure from the original disk with bbdemux, and the stutter was gone. So it seems that the variable was the way that MTR created the m2v file. The MTR demux made a perfect AC3 file (as far as I can tell), so that particular mission was accomplished.

[geezerbuttz]

you need to fix the time code...

[WiseWeasel]

Geezer, how would one do such a thing? Why is it required?

[geezerbuttz]

mediastreamclip has an ultra fast timecode fixer...

All M2V streams have timecode in them , if you rip chapters / cells that are not asyncronous then you need to rebuild the time code in the stream to enable it to play smoothly.
This is if you merge the non async cells back together of course.....

and if your original stream was muxed with bad audio , there isno telling what happened to the time code...

I guess that BBDemux fixes the time code on the fly .. maybe not.

If more people have this issue I will do some more code runs on it...

[DeadLily]

The sound wasn't faulty bad; it was just mixed too low. All I did was tweak the volume and create a new AC3 track. Even with the picture stutters, it all stayed in sync. Sync wasn't an issue. The stutters were such that the frames would double up every second or so, and then skip ahead to where it was supposed to be. Therefore, it managed to stay in sync.

[geezerbuttz]

right , i just repeated your experiment.... here is the result....

MTR 2.6...

took M2V encoder in Compressor + AC3 encoded in MPACK......

added to toast DVD ( PAL ) project , toast requested audio track , added AC3 audio file.

Muxed , and created DVD == Complete Success.

( playback was fine , no stuttering )

ripped disk in MTR 2.6 , extarcted complete stream , demuxing to M2V & AC3

MTR completed rip without issues....

took ripped streams back into toast , created new DVD with ripped streams , toast muxed , and burned the DVD ...

played the DVD back in Mac + Standalone player == Noi stuttering or breakdown.

In a nutshell I was un-able to reproduce your results.

One thing You do not state is , How did you encode your video ? did you let toast do it ? did toast encode the audio?

Im wondering if toast provides a %100 complient m2v stream....

let me know please mate..

GB

[JoachimS]

In my newbie days I made a mistake by encoding audio with 44.1kHz instead of 48kHz as it is standard with DVDs.

The result was also a stuttering effect.

Cheers,

JoachimS

[DeadLily]

1) It actually had gone through a couple of permutations, so where it may have got corrupted is hard to say. The very first encoder was Bitvice (NTSC), working from a Final Cut Pro movie (29.97). The m2v from that was then fed into DVDSP 1.5 with an AC3. A VIDEO_TS folder was created. I went through this process eight times with different titles.

2) THEN... once I had burned and tested those titles individualy, I opened Toast and dragged the eight VOB files from their separate VIDEO_TS folders into one single project. (Just the VOBs, not the IFOs or BUPs; Toast doesn't need them.) Toast made a menu for me, spent some time re-encoding them, and made a new VIDEO_TS folder.

3) After testing this, I realized that one of the titles had the sound volume too low. I have bbdemux, but I decided to try MTR's new feature. I extracted the offending title's m2v and AC3, fixed the AC3, and opened the recent Toast project to re-insert the new AC3 and MTR's m2v. Built another VIDEO_TS folder. Video stuttered only in the modified title.

4) Repeated step 3 with bbdemux. Stutter gone.

Hope this helps.

[geezerbuttz]

i think the clue is in the framerate 29.967..... this may of had a pulldown flag inserted by toast , this would cause the stuttering...

the pulldown would cause the player to playback at 23.976 , so the video has to jump to catch up the muxed audio.


If so , its a toast bug....

[DeadLily]

Curious that Toast would do that to the MTR m2v and not the bbdemux m2v.

But whatever. I eventually got the results I wanted, so no complaints here.