This script allows you to configure advanced subtitle track selection based on the current audio track and the names and language of the subtitle tracks. The script will automatically disable itself when mpv is started with --sid not set to auto, or when --track-auto-selection is disabled.
Configuration is done in the sub-select.json file, stored in the ~~/script-opts/ config directory.
The syntax and available options are as follows:
[
{
"alang": "jpn",
"slang": "eng",
"blacklist": [ "sign" ],
"whitelist": [ "english", "song" ]
}
]
alang and slang are the language codes of the audio and subtitle tracks, while blacklist and whitelist are optional filters that can be used to choose subtitle tracks based on their track names. The blacklist and whitelist will trigger if any of their entries are present in the track name.
alang and slang can also be arrays of valid codes to allow matching with multiple language codes.
If multiple slang languages are included, then the first code to match to a track will be the one used.
All matching is done using the lua string.find function, so supports patterns. For example eng? could be used instead of eng so that the DVD language code en is also matched.
The script moves down the list of track preferences until any valid pair of audio and subtitle tracks are found. Once this happens the script immediately sets the subtitle track and terminates. If none of the tracks match then track selection is deferred to mpv.
There are a number of strings that can be used for the alang and slang which have special behaviour.
alang:
| String | Action |
|---|---|
| * | matches any language |
| no | matches when no audio track is selected |
slang:
| String | Action |
|---|---|
| * | matches any language |
| no | disables subs if alang matches |
| default | enables subtitles with the default tag |
| forced | enables subtitles with the forced tag |
The script supports two commands to control subtitle selection.
This command will force subtitle selection during runtime based on the current audio track.
This command will enable/disable the script. Valid arguments are enable, disable, and toggle. If the script gets enabled then the current subtitle track will be reselected.
The detect_audio_switches script-opt allows one to enable Auto-Switch Mode. In this mode the script will automatically reselect the subtitles when the script detects that the audio language has changed.
This setting ignores --sid=auto, but when using synchronous mode the script will not change the original sid until the first audio switch. This feature still respects --track-auto-selection.
This mode can be disabled during runtime wi the sub-select script message shown above.
The script has two different ways it can select subtitles, controlled with the preload script-opt. The default is to load synchronously during the preload phase, which is before track selection; this allows the script to seamlessly change the subtitles to the desired track without any indication that the tracks were switched manually. This likely has better compatability with other options and scripts.
The downside of this method is that when --aid is set to auto the script needs to scan the track-list and predict what track mpv will select. Therefore, in some rare situations, this could result in the wrong audio track prediction, and hence the wrong subtitle being selected. There are three solutions to this problem:
Disable the hook by setting preload=no. This is the simplest and most efficient solution, however it means that track switching messages will be printed to the console and it may break other scripts that use subtitle information.
Force the predicted track to be correct by setting aid to the predicted value. This can be enabled with force_prediction=yes.
This method works well, but is not ideal if one wants to utilise a more refined audio track selector, or if mpv's default is more desirable.
Check the audio track when playback starts and compare with the latest prediction, if the prediction was wrong then the subtitle selection is run again. This can be disabled with detect_incorrect_predictions=no. This is the best of both worlds, since 99% of the time the subtitles will load seamlessly, and on the rare occasion that the file has weird track tagging the correct subtitles will be reloaded. However, this method does have the highest computational overhead, if anyone cares about that.
Auto-Select Mode enables this intrinsically.
The sub_select.conf file contains all of the options for the script and their defaults. The sub-select.json file contains an example set of track matches.