Suggestion:Add a modify to audio set default

[Selur]

Send you a link to a dev version, which should allow to set 'default' to 'true' if 'Base->Processing->Audio' is set to 'custom'.
So you could:

• set 'Base->Processing->Audio' for example to 'passthrough (all)', to populate the list when loading your files
  
• load your files
  
• change 'Base->Processing->Audio' to 'custom'
  
• switch to the 'Audio'-tab, right-click on the entries you want to change to 'default' 'true' and select 'set default'.
  

Cu Selur

[i990049]

I've tested it many times and I'm still having problems. The video has three audio tracks, don't care about the picture quality and sound quality. the first audio track is MP3, the second audio track is AAC, the third audio track is OPUS, and the third audio track is default. I have chosen to set the second audio track of the output file AAC as the default audio track, but the default audio track of the output file is the first MP3, and the output file is bigger than the the original file. What is the problem? Here are the test file and debug.

https://wwi.lanzoup.com/ippIJ1jnnwdc

[Selur]

I'll look at it.

Cu Selur

[Selur]

Think I found the problem. (updated the list item only in the ui not the model)
Send you a new link.

Cu Selur

[i990049]

This time the audio default works. Why the output file is bigger than the original？Passthrough merging without encoding will change the file size？

PS：Thank you，best wishes to you.

[Selur]

How much is the size difference?

[i990049]

10M，I don't know what became bigger

[Selur]

Hmm,.. with 10MB I would suspect that it is caused by some index or similar, a newer mkvmerge option might add to increase compatibility.
Can you share a detailed mediaino report of both files?

Cu Selur

[i990049]

Here is the output file. The origina file is in testvideo-debug07.zip. I already sent you before.
https://wwi.lanzoup.com/ii1Fo1jsgd3g
Mediainfo show the original file is 92.4Mib，but the output file is 99.0 MiB. video/audio/subtitles files size are nothing changed except the total size.

[Selur]

Okay, according to MediaInfo, the original was muxed using mkvmerge 71.1 and the new version used 81.0.
The video steam, the audio and the subtitles steams have the same size in both.
Like I suspected, this is probably caused due to some additional indexes mkvmerge added in newer versions.
I suspected this was caused by one of the options under: 'Config->Containers->MKV' but that was not the case.
Also, simply remuxing the file with mkvmerge resulted in the same file size as the original.

After some searching, I found what is causing the majority of the difference.
Hybrid uses '--compression -1:none' for compatibility,

--compression TID:n

Selects the compression method to be used for the track. Note that the player also has to support this method. Valid values are 'none', 'zlib' and 'mpeg4_p2'/'mpeg4p2'.

The compression method 'mpeg4_p2'/'mpeg4p2' is a special compression method called 'header removal' that is only available for MPEG4 part 2 video tracks.

The default for some subtitle types is 'zlib' compression. This compression method is also the one that most if not all playback applications support. Support for other compression methods other than 'none' is not assured.

see: https://mkvtoolnix.download/doc/mkvmerge.html#2.8'
using 'zlib' instead of 'none' caused the size to shrink to 94.7MB (original: 92.3 MB), so there are still 1.6 MB difference which are likely caused by one of the options under 'Config->Containers->MKV'.

I thought that 'Config->Containers->MKV->Disable header compression' would disable the addition of '--compression -1:none' but there are some additional internal cases in which the headers get still added. (not sure why these are there)
=> will look into it more tomorrow.

Cu Selur