Using MKVToolNix causes almost 1gig loss

[agon024]

I thought that MkvToolNix was supposed to be lossless when muxing but when I open an MKV, take the bottom audio track and move it to the top (default) position then remux, the file size goes from 10.2 gigs to 9.3 gigs. So this is obviously not lossless.

Am I doing something wrong? Because every time I do this I lose file size.

[Selur]

If your input is a transport stream then the loss might be:
a. due to lower container overhead (transport streams can have humongous overheads)
b. loss of bit rate stuffing.

Not totally sure, cut iirc if you feed content with truehd(ac3) combi-streams only the truehd part is kept.

-> if you want something more qualified, share more details on what you are doing,..

Cu Selur

[agon024]

If your input is a transport stream then the loss might be:
a. due to lower container overhead (transport streams can have humongous overheads)
b. loss of bit rate stuffing.

Not totally sure, cut iirc if you feed content with truehd(ac3) combi-streams only the truehd part is kept.

-> if you want something more qualified, share more details on what you are doing,..

Cu Selur

Ya, the default audio stream to start with is TrueHD Atmos 7.1. The second one is AC-3 5.1. I move the AC-3 to the top(default position) above TrueHD.

This is how it starts.


[Attachment 57652 - Click to enlarge]

I just click and hold the AC-3 track and drag it above the TrueHD Atmos then click "start multiplexing". So by doing this am I hurting the TrueHD Atmos track in anyway?

[johns0]

Nope.

[aedipuss]

weird. afaik you can only click/hold and drag a track DOWN the list with mkvtoolnix. and not sure how you got that as a 10gb file as it's 48gb off the disc.

[agon024]

and not sure how you got that as a 10gb file as it's 48gb off the disc.

ffmpeg nightly beta

[Ennio]

afaik you can only click/hold and drag a track DOWN the list with mkvtoolnix

Actually, I can't remember mkvtoolnix without being able to move tracks both up & down. You can also activate buttons for it in preferences.


[Attachment 57663 - Click to enlarge]

[aedipuss]

afaik you can only click/hold and drag a track DOWN the list with mkvtoolnix

Actually, I can't remember mkvtoolnix without being able to move tracks both up & down. You can also activate buttons for it in preferences.


[Attachment 57663 - Click to enlarge]

thanks but it you still can't click/hold/drag a track and move it up, only down.

[edit] i seem to recall in old versions you might have been able to drag/drop up but it went away awhile ago.

[aedipuss]

agon024 what version of mktoolnix are you using? i'd suggest updating to the latest and trying again to see it if makes a difference, as older versions had ways to shrink file sizes that aren't used anymore for compatibility reasons.

[Ennio]

thanks but it you still can't click/hold/drag a track and move it up, only down.

You got me doubting. I just checked by adding a mpls from BD ISO which contains both TrueHD with embedded AC3 and DTS-MA. I can move all audio-, video- and PGS tracks independently up and down. Both with the buttons and by dragging. I am on latest version 54.0.0. Only item that won't move is 'chapters'.

[agon024]

agon024 what version of mktoolnix are you using? i'd suggest updating to the latest and trying again to see it if makes a difference, as older versions had ways to shrink file sizes that aren't used anymore for compatibility reasons.

@aedipuss, I am using the most current versions (and I mean current) version 54.0.0.7. And BTW you can move tracks up and down with out a problem (since I've been using it), just not chapters.

[aedipuss]

thanks for letting me know. here all dragging up does is highlight everything on the way up.

[sneaker]

Not totally sure, cut iirc if you feed content with truehd(ac3) combi-streams only the truehd part is kept.

This is not true. Mkvmerge just separates the combined track into 2 separate tracks.

https://gitlab.com/mbunkus/mkvtoolnix/-/wikis/TrueHD-and-AC-3

[aedipuss]

LOL - thanks Moritz! in the new v55 i can once again drag and drop up or down.