Windows script to insert new AAC audio into MKV container

[rbjtech 4254]

In an effort to make all my media as 'streaming' friendly as possible (to eliminate transcoding) I've been developing a script to automate adding a new default AAC Audio track into MKV's and thought I'd share it on here as I think it works rather well. (but test/use at your own risk..)

 

ps - I know there are tools online that do this (Popcorn etc) but none gave me the level of control that I wanted.

 

The script reads a text file containing the UNC/filenames that you want converted -

 

a) Checks the file using ffprobe to determine the 1st Audio track - if mp3 or AAC already, then it skips the file.

b ) Uses ffmpeg to convert the 1st Audio track (from AC3, DTS, HD Audio etc) to Stereo AAC and also bumps the volume to equal the DTS/AC3 (approx).

c) Inserts this track as Default Audio - retaining all the other Audio tracks as well.

d) Note - this script does not retain internal subtitles - this is by design as I use external .srt only - again to maximise streaming/device non-transcode compatibility. 

e) Checks the success of ffmpeg and if no errors - then deletes the original file and renames the temp file to the original filename.  ** REM these lines out if you want to retain the original **

f) Logs everything including keeping the ffmpeg log.

 

To generate the input file (films.txt) then just use 'dir /a-s /b /s "\\server\share\directory\*.mkv" > films.txt' from the root and this will list all the MKV files in all sub-directories for example.

 

I suggest testing on a sample file first to ensure it does what you expect - but this has been extensively tested on all my MKV files (1000's..) and thus far has not failed once.

 

To use :-

 

rename the batchaac.bat.txt file to .bat 

modify the .bat file (notepad etc) with the location of your ffmpeg/ffprobe - not sure if you can use emby's version - untested.

example films.txt given but obviously generate your own

run 'batchaac' from a command prompt - it will create a \batch and \batch\logs directory to keep the logs\temp files in.

 

Enjoy.

films.txt

batchaac.bat.txt

Edited August 29, 2019 by rbjtech