e0qdk

I don't know how to do it with KDE's tools, but on the command line with ffmpeg you can do something like this:

ffmpeg -i video_track.mp4 -i audio_jp.m4a -i audio_en.m4a -map 0:v -map 1:a -map 2:a -metadata:s:a:0 language=jpn -metadata:s:a:1 language=eng -c:v copy -c:a copy output.mp4

Breaking it down, it:

• runs ffmpeg
• with three inputs (-i flag) -- a video file, and two audio files.
• The streams are explicitly mapped into the result, counting the inputs from 0 -- i.e. -map 0:v maps input 0 (the first file) as video (v) to the output file and -map 1:a maps the next input as audio (a), etc.
• It sets the metadata for the audio tracks -metadata:s:a:0 language=jpn sets the first audio track (again counting from 0...) to Japanese; the second metadata option sets the next audio track to English.
• -c:v copy specifies that the video codec should be copied directly (i.e. don't re-encode -- remove this if you DO need to re-encode)
• -c:a copy specifies that the audio codec should be copied directly (i.e. don't re-encode -- remove this if you DO need to re-encode)
• output.mp4 -- finally, list the name of the file you want the result written into.

See documentation here: https://ffmpeg.org/ffmpeg.html

If you need another language in the future, I think the language abbreviations are the three letter codes from here: https://en.wikipedia.org/wiki/List_of_ISO_639-2_codes -- but I'm not certain on that.

DOSBox runs on both Linux and Windows (and probably Mac too?); I was suggesting it since you might be able to replace the dying DOS computers with a modern system and just launch the legacy system as an application under it. (You might be able to do the same with a VM as well, but DOSBox came to mind first and may be easier to setup and distribute.)

Just a thought. If it's not useful, feel free to disregard.

Can you run the DOS software under DOSBox?

https://github.com/microsoft/MS-DOS

Discussion on HN yesterday: https://news.ycombinator.com/item?id=40163405

Steam has a soundtrack listed for the more expensive releases of the game ("deluxe edition", etc), but I'm not sure what format the audio is in exactly or if you can buy it separately from the game itself there. (I don't have very many soundtracks from Steam, but the ones I do have are either in MP3 or WAV)

The Japanese text on the bottom of the left image says: Sapporo (Draft) Black Label beer. I can't tell what the four characters under 生 are though. (Too blurry for me to figure out.)

Edit: those characters might be 非熱処理 -- meaning unpasteurized.