Previously, you could tag audio channel assignments using QuickTime Pro 7. However, QuickTime Pro 7 is a 32-bit application. Starting with the release of macOS Catalina, macOS supports 64-bit applications only.
Instead, you can use Compressor 4.4.5 to tag audio channel assignments for QuickTime movies using Compressor’s command-line interface. Use the command-line option -relabelaudiotracks followed by the channels you want to tag and their values. See Audio channel layouts in Compressor for more on audio channel layouts.
The supported values for audio tagging are:
Label | Description |
|---|---|
L | Left |
R | Right |
C | Center |
LFE | LFE Screen |
Ls | Left Surround |
Rs | Right Surround |
Lc | Left Center |
Rc | Right Center |
Rsl (or Rls) | Rear Surround Left (or Rear Left Surround) |
Rsr (or Rrs) | Rear Surround Right (or Rear Right Surround) |
Lt | Left Total |
Rt | Right Total |
LtRt | Matrix stereo (Lt Rt) |
stereo | Stereo (L R) |
Examples:
Given a QuickTime Movie file with two audio tracks where the first audio track contains the Left audio channel and the second audio track contains the Right audio channel, type the following at the command line:
/Applications/Compressor.app/Contents/MacOS/Compressor -relabelaudiotracks L R <path_to_Quicktime_Movie_source_file>
Similarly, given a QuickTime Movie file with one audio track where the track contains both the Lt and Rt audio channels (that is, matrix stereo), type the following at the command line:
/Applications/Compressor.app/Contents/MacOS/Compressor -relabelaudiotracks LtRt <path_to_Quicktime_Movie_source_file>
The above commands overwrite the audio assignments in the original source file, which can speed up the process. To save to a new file, add -locationpath to the command, for example:
/Applications/Compressor.app/Contents/MacOS/Compressor -relabelaudiotracks L R <path_to_Quicktime_Movie_source_file> -locationpath <path_to_output_file>
and
/Applications/Compressor.app/Contents/MacOS/Compressor -relabelaudiotracks LtRt <path_to_Quicktime_Movie_source_file> -locationpath <path_to_output_file>
See Intro to shell commands in Compressor for more information using the command line. And in the command line tool, you can display help using: /Applications/Compressor.app/Contents/MacOS/Compressor -help.