MKV encode needs demux and audio file exchange

[loninappleton]

I have an mkv encode made from disc in Handbrake.

Previously I have used AVI tools especially Auto Gordian Knot
to get my audio where I can work on it (level audio) using the Goldwave audio editor.

Virtual Dub Mod allowed me to change the audio file for one of these leveled ones using the Stream List . How can this be accomplished with MKV tools such as Toolnix, Cleaver, or MeGUI etc?

What is the best way to get started with MKV options? I have scant knowledge of MeGUI but would like to get started with that. Or perhaps there are newer tools for the beginner (?)

I wish to work with open source (freeware) where possible and preferable.

[foxyshadis]

For working directly with the mkv: Install Audacity, download the ffmpeg 2.2 libraries for it (http://manual.audacityteam.org/o/man/faq_installation_and_plug_ins.html#ffdown) and put them in Audacity's ffmpeg folder, then you can open any video file directly to work on its audio. You can then export to AAC again once you've edited and remux with MKVMerge (removing the original track). From Audacity, you can also export to wav and use Goldwave and then back to Audacity (or another program) to use AAC, but seems like kind of a waste of effort.

If you do this, you should switch Handbrake to export audio as "Auto Passthru" to minimize the generation loss of editing the tracks.

You can also demux the audio tracks from the final mkv, but since Audacity can open video files directly, the only reason to do it is if you saved more than one audio track, since Audacity only opens the first.

[loninappleton]

Thanks for reply.

I will recheck and make sure I have the Audacity with the plugin installed correctly.

MKV Merge must be the tool where I can install a new audio track.

An interim step with the audio would be run a program that only works with .wav files called The Levelator. It is free and from The Conversations Network. It was designed to match levels for podcasts on various microphones and I've come to use it often.

http://web.archive.org/web/20130729204551id_/http://www.conversationsnetwork.org/levelator/

Please say how AAC audio fits into this.

In some previous attempts to alter the .wav I have found that
my audio went out of sync. I'm hoping that with the newer encoding tools that will be avoided. Nevertheless Handbrake has worked well for me where this audio manipulation was not needed.

[loninappleton]

Today I have an encode going after following the instructions to install ffpeg in Audacity. I used the locate option and things seem to be where they should be.

I've begun a fresh encode from the source disc with the defaults in Handbrake:

Mp4 is the file type
h264 codec
mkv container
Constant Quality 25
Auto Pass through on the Audio tab.

This business with the container is confusing. I have not selected h265.

From here you are saying drag the completed encode to Audacity and let that demux the audio (?)

I know Audacity can do this. Goldwave can do this as well.

From there I see the process as Save to WAV for my processing job.

Please correct any errors here.

[loninappleton]

Pressing on, today I loaded the mkv into Audacity.

I understood now that Pass Through means the AAC audio shown in Media Info for the original encode.

Ok for that. In Audacity I see that it has a Leveller option in Effects. I selected heaviest at 80 db as a test.

But Audacity is different from Goldwave and I cannot see where to raise the volume. I'm seeking a 20% increase. The other phraseology like Gain and so forth may apply. Maybe it's in Help someplace. Please advise.

[loninappleton]

For comparison I did my regular procedure through Goldwave and The Levelator.

I compared the wave form. Levelator working in .wav format is still superior and I'd guess for this reason: My jobs are from live stage production. All of the Levelator services are targeted on the voice and so big tympany rolls etc. are muted and the voice where low is brought up.

The final merge operations in MKV merge still have to be dealt with plus reconverting to AAC or whatever process you suggest.

After that I have a few more questions regarding splitting the big file down into two 'acts.'