Stereo to Dual Mono Audio ?

I just downloaded HitFilm Express, and my first simple task to do with it is to take a ProRES clip with one CD track and one MIC track as L/R... trim the clip, merge the audio to mono (or use the mic track alone as mono) and output a H.264 file.
Seems simple enough...
Currently i'm stuck on the fact that HitFilm imports as stereo with no option to separate the tracks to dual mono.
After a bit of research it appears people have been asking for this for quite a few years, and the best suggestion anyone comes up with is to use an external audio editor to accomplish what should be achieved within HitFilm in a few clicks.
Its not uncommon for people to record one track on Left and one on Right, so i'm confused as to why this isn't a stock feature?


  • You could try duplicating the track, and change the balance in the mixer to Left and Right respectively. 

  • Thanks Emecorp,
    I tried that but with the track imported as stereo it just pans left to left and right to right.

  • Aladdin4dAladdin4d Moderator
    edited November 2017

    This is one where it's probably a good idea to learn some FFMpeg commands. Since you mentioned ProRes, I'm going to assume you're using a Mac and I don't do any Mac scripting so my example here probably won't work as is but something resembling this:

    for f in *.mov;do ffmpeg -i "$f" -filter_complex "channelsplit=channel_layout=stereo[FL][FR]" -map "[FL]" "${f%mov}left.wav" -map "[FR]" "${f%mov}right.wav";done

    Should extract the audio to left and right mono wav files for each MOV in the folder it's run in

  • I use Mac, PC and Linux... I mention ProRes becuase I use Atomos Samurai recorders, which record in ProRes.
    I really feel that this is something HitFilm should include. I just cant picture anyone who is serious about their film making resorting to the command line to import their footage. 
    There is no real reason it cant be integrated in the software.
    This is a simple feature that really should be just a few clicks and yet every time it comes up, the suggestion is to fix it with an audio editor like Audacity, or FFmpeg.
    There's so many different ways to get it done in other NLE's, but I just couldn't find a way to make it work with HitFilm and I just don't understand why.

  • @Tziware Historically HitFilm's audio support has been anemic but it does get better in every version. I'm pretty sure this is on the Wishlist but you might want to add your voice too. Personally, I'm hoping for compression in the next major release.

    As far as resorting to the command line for ingesting footage - Yeah that happens all the time, even if you don't realize it. FFMpeg is the single most widely used tool on the planet. It goes from rolling your own solution with a script to being incorporated in highly regarded programs like Resolve. Server side solutions? FFmpeg or a fork of it. Anything on Linux? I know there are a couple of things out there using Gstreamer but everything else, and I really mean everything, uses FFMpeg or a fork. Windows transcoding tools that support ProRes? All of them including the ridiculously expensive Cinemartin Cinec. It's everywhere.

    Since you do use Windows some, this batch file will work after a minor change. I use this almost daily for extracting the audio from MTS files so you need to change the MTS reference to MOV. It assumes you have a 64 bit static build of FFMpeg at C:\FFMpeg64-Static. I would add a scripts folder to that and put it there, then create a shortcut to add to the right click Send To menu. Once set up, all you have to do is right click a folder, select Send To then the entry for this script and extraction will happen. It opens a command window, names the folder it's working on, updates the progress then pauses to let you review what it did. Hit any key to exit. Yes it is a little bit of a pain to set up but once you do, you never have to worry about it again and you have the option of adding other scripts for specific tasks.

    echo %1
    for %%a in ("%1\*.MTS") do C:\FFMpeg64-Static\Bin\ffmpeg -i "%%a" -filter_complex "channelsplit=channel_layout=stereo[FL][FR]" -map "[FL]" "%1\%%~na_left.wav" -map "[FR]" "%1\%%~na_right.wav"

    For the record I started extracting the audio long before HitFilm even existed and I personally find it always pays off in the long to do that regardless what other tools I'm using. I use ImageMagick with a couple of other scripts the same way for batch processing images for many of my projects too.

  • Audio management in HitFilm is definitely incomplete.

    I usually use mono source files (voice, sfx) and when I need music that's added in post. I and haven't really use the "record one in the left, and one in the right channel" method, I didn't know it was that common.

    So I think you are better with a external audio editor.  My suggestion would be Cockos REAPER


  •  Yep quite common, even moreso with DSLR shooters.
    E.G running a mono mic into a DSLR with one channel at a good volume, and the other at 1/2 that volume.
    Same problem... no way to just play the one audio track as a mono.

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