MakeMKV vs DVDfab : Problem Splitting with MKVmerge

[hydrogin]

I've been using MakeMKV and MKVmerge to create short video clips to play on a WDTV Live+. These 2 to 3 minute clips will be used by a friend to demo his product at this week's CEDIA Expo in Atlanta (he'll be in the Sony booth for anyone who might be attending).

The problem

Clips split out from a full-length MKV created by MakeMKV have an audio sync delay at the beginning of the clip. But when I replace MakeMKV with DVDfab in my tool flow, the problem goes away (audio in all split clips are in sync).

This flow produces bad audio sync:

MakeMKV --> MKV --> MKVmerge 4.3 (timecode split, header-compression off) --> 3 MKV files
MakeMKV --> MKV --> MKVmerge 4.0 (timecode split) --> 3 MKV files

This flow produces good audio sync:

DVDfab --> MKV --> MKVmerge 4.3 (timecode split, header-compression off) --> 3 MKV files
DVDfab --> MKV --> MKVmerge 4.0 (timecode split) --> 3 MKV files

Here are some notes and observations:

1. The audio sync problem only occurs when the playback device is a WDTV. The short clips play fine on a Windows 7 PC using MPC Home Cinema.
2. This problem only occurs for blu-ray discs (many titles have been tried). The flow works fine for DVD discs.
3. Tried MakeMKV 1.58 and 1.60, no diffs in behavior.
4. Tried MKVmerge 4.3 and 4.0, no diffs in behavior.
5. Header compression was turned OFF when MKVmerge 4.3 was used (to avoid an issue the WDTV has with compression).
6. The latest WDTV Live+ production 1.03.29 and beta 1.03.38 firmware were used. No diffs in behavior.
7. The only non-default options used in MKVmerge was to specify two timecodes (hh:mm:ss) where splits in the timeline should occur.
8. Explicitly specifying the video frame rate in MKVmerge makes no difference.
9. The full-length MKV's created by MakeMKV and DVDfab play fine and are in sync.
10. I have posted this issue at Western Digital's Community forum, no good feedback yet.

Questions:

1. Has anyone experienced this problem before?
2. Any suggestions for making this flow work with MakeMKV?

Thanks.

[setarip_old]

Hi!

1) Have you logged the video and audio codecs used with each clip - to see if there's any correlation with codecs and your problem?

2) Has your friend obtained the proper releases (or possibly paid for) for using clips from commercial videos?

[hydrogin]

setarip_old said:

> 1) Have you logged the video and audio codecs used with each clip - to see if there's any correlation with codecs and your problem?

All appear to be VC-1 and AC3. No AVC, DTS, etc. in the mix.

One correlation we have now is that the problem always occurs when MakeMKV is used to create the source MKV. A second correlation is the problem never occurs when DVDfab is used to create the MKV. The splitting tool, MKVmerge, is always run the same way regardless of who created the source MKV. This means the only variable is the MKV ripper/generator (i.e. MakeMKV and DVDfab).

These kinds of problems are often difficult to solve because there are so many "parties" involved. Sometimes a single party is to blame. Other times its the combination of parties that's the problem. Nevertheless, I hope there's someone here who's interested in using MakeMKV in a similar manner.

> 2) Has your friend obtained the proper releases (or possibly paid for) for using clips from commercial videos?

I don't know but assume his company is on good legal standing. They're long-time exhibitors at CES, Cedia, etc.

[setarip_old]

1) Do the INITIAL (Before running through MKVMerge) MakeMKV .MKVs playback in synch?

2) Why are you running the .MKVs through MKVMerge?

3) What specific Blu-ray titles did you extract clips from?

[hydrogin]

1) Do the INITIAL (Before running through MKVMerge) MakeMKV .MKVs playback in synch?

2) Why are you running the .MKVs through MKVMerge?

3) What specific Blu-ray titles did you extract clips from?

1. All the full length mkv's from both MakeMKV and DVDfab play fine and are in sync.

2. As mentioned in the first post, MKVmerge is being used to split a full-length mkv into multiple smaller mkv's. The objective is to obtain a short 2-3 minute video clip of a specific scene. MKVmerge users do this by specifying a timecode (hh:mm:ss) for any number of desired splits along the movie's timeline. Splitting is one of the Global functions in MKVmerge's GUI. The only data input into MKVmerge is the full-length mkv.

3. BD titles tried so far include Cloverfield, Dark Knight, Planet Earth, Pride and Glory, etc. The DVD Almost Famous was used to see if this issue extends to DVD's (as mentioned previously, it does not).

[wasim274]

I also use MKVMerge to take out the compressed headers and also to include .srt subtitles (converted from PGS) as WDTV HD Live can't deal with either in MKV form. When experimenting with this I decided to use a short excerpt from a BluRay. I had to give up as lip sync was out (by a significant amount) on the excerpt. It was perfectly OK on the full movie.

[hydrogin]

I also use MKVMerge to take out the compressed headers and also to include .srt subtitles (converted from PGS) as WDTV HD Live can't deal with either in MKV form. When experimenting with this I decided to use a short excerpt from a BluRay. I had to give up as lip sync was out (by a significant amount) on the excerpt. It was perfectly OK on the full movie.

What a coincidence!

I had a very similar experience a month ago ... was using MKVmerge to mux in IDX/SubVOB subtitles converted from Avatar's PGS forced subtitles. The end result played OK but suffered from lip sync problems whenever WDTV Live Plus's FF was used. I thought something was wrong with my subtitle conversion steps, but perhaps its related to MergeMKV-based process flows.

Mike has contacted me and I'll be running some experiments to aid in debug this weekend. Thanks for your input.

[HeadlessCow]

I've seen the same problem with splitting music videos I've ripped from DVD when all the videos are dumped in the same file and organized by chapter.

If it helps at all, I discovered that:

MakeMKV --> MKV --> MKVCleaver --> m2v, wav, chapters.xml --> MKVmerge 4.4 (timecode split, header-compression off) --> Many MKV files

works fine.

Also:

MakeMKV --> MKV --> MKVmerge 4.4 --> MKV

results in out of sync by the end of the file if I skip around. It appears to stay in sync if I just let it play, but I didn't let it sit for an hour to verify that it's good all the way at the end of the last music video.

The only real difference I can see between the MakeMKV MKV and the MKVmerge MKV is that the audio track in the original has:
Default duration: 1.667ms (600.000 fps for a video track)
while the one output by MKVmerge has:
Default duration: 31.250ms (32.000 fps for a video track)

Hopefully something there is helpful as a workaround (or as a clue to what's causing the issue)

[mike admin]

The only real difference I can see between the MakeMKV MKV and the MKVmerge MKV is that the audio track in the original has:
Default duration: 1.667ms (600.000 fps for a video track)
while the one output by MKVmerge has:
Default duration: 31.250ms (32.000 fps for a video track)

Thanks for posting this. Please download mediainfo from sourceforge and post it's output for both files - that should provide more details.