MKVPriority assigns configurable priority scores to audio and subtitle tracks, similar to custom formats in Radarr/Sonarr. MKV flags, such as default and forced, are automatically set for the highest-priority tracks (e.g., 5.1 surround and ASS subtitles), while lower-priority tracks (e.g., stereo audio and PGS subtitles) are deprioritized.

Important

MKVPriority modifies track flags in place using mkvpropedit (no remuxing), allowing media players to automatically select the best audio and subtitle tracks according to your preferences.

Features

• Assigns configurable priority scores to audio and subtitle tracks (similar to custom formats in Radarr/Sonarr)
• Automatically sets default/forced flags for the highest priority tracks (e.g., Japanese audio and ASS subtitles)
• Deprioritizes unwanted audio and subtitle tracks (e.g., English dubs, commentary tracks, signs/songs)
• Identifies forced subtitle tracks using dialogue-density heuristics without relying solely on track names
• Suppresses default flags during native audio playback to prevent unnecessary subtitles for dialogue
• Evaluates external sidecar subtitles alongside embedded tracks and updates their filename flags on disk
• Periodically scans your media library using a cron schedule and processes new MKV files with a database
• Integrates with Radarr and Sonarr using a custom script to process new MKV files as they are imported
• Supports extension modules for optional, user-defined post-processors to handle specialized workflows

Docker Image

A Docker image is provided to simplify the installation process and enable quick deployment.

docker run --rm -v /path/to/media:/media ghcr.io/kennethsible/mkvpriority /media

Use a Custom Config

You can specify your own preferences by creating a custom TOML config that defines track filters by name and assigns scores by property. To override the default config, use a bind mount:

docker run --rm -u ${PUID}:${PGID} \
  -v /path/to/media:/media \
  -v /path/to/mkvpriority/config:/config \
  ghcr.io/kennethsible/mkvpriority /media \
  --config /config/custom.toml

Important

Before starting the Docker container, you should pre-create the config folder on the host. Otherwise, Docker will create the folder as the root user, causing Python to raise a PermissionError.

Use an Archive Database

You can periodically process your media library using a cron job and an archive database. To keep track of processed files, create an archive.db file and use a bind mount:

docker run --rm -u ${PUID}:${PGID} \
  -v /path/to/media:/media \
  -v /path/to/mkvpriority/config:/config \
  ghcr.io/kennethsible/mkvpriority /media \
  --archive /config/archive.db

TOML Configuration

All behavior is configured through TOML files, which assign priority scores to track properties, such as languages and codecs, and define custom filters for track names, such as "signs" and "songs." To get started, check the example TOML file that has been provided (see here).

Override Config Rules

You can override config rules dynamically without modifying your TOML files using the --override argument. This is designed to address edge cases with non-standard or mislabeled metadata. CLI overrides use dot notation (section.key=value) and automatically parse values (numbers, booleans, strings, etc.)

docker run --rm -u ${PUID}:${PGID} \
  -v /path/to/media:/media \
  -v /path/to/mkvpriority/config:/config \
  ghcr.io/kennethsible/mkvpriority /media \
  --override 'subtitle_profiles.global.languages.mul=70' \
  --override 'subtitle_profiles.dialogue.filters.yellow=-10000'

Note

You can pass --override multiple times to chain adjustments together, which take precedence over all settings defined in your loaded TOML file. If a filter name contains spaces, remember to wrap the entire argument in quotes.

Example: Subtitle Codecs

[subtitle_profiles.global.codecs]
"S_TEXT/ASS" = 30    # Stylized (Advanced SubStationAlpha)
"S_TEXT/SSA" = 30    # Legacy Stylized (SubStationAlpha)
"S_TEXT/UTF8" = 20   # Plain Text (SubRip/SRT)
"S_TEXT/WEBVTT" = 20 # Web-Based Video Text (Used in Streaming)
"S_HDMV/PGS" = 10    # Image-Based (Used in Blu-rays)
S_VOBSUB = 10        # Legacy Image-Based (Used in DVDs)

Radarr/Sonarr Integration

You can process new MKV files as they are imported into Radarr/Sonarr by adding the custom script mkvpriority.sh and selecting 'On File Import' and 'On File Upgrade'. In order for Radarr/Sonarr to recognize the custom script, it must be visible inside the container. When using Radarr/Sonarr, you can assign scores to the original audio language (org).

Note

To add a custom script to Radarr/Sonarr, go to Settings > Connect > Add Connection > Custom Script.

mkvpriority:
  image: ghcr.io/kennethsible/mkvpriority
  container_name: mkvpriority
  user: ${PUID}:${PGID}
  environment:
    WEBHOOK_PORT: "8080"
    MKVPRIORITY_ARGS: >
      --archive /config/archive.db
  volumes:
    - /path/to/media:/media
    - /path/to/mkvpriority/config:/config
  ports:
    - 8080:8080
  restart: unless-stopped

Important

If you are not using "mkvpriority" as the name of your container, you will need to update it in the custom script. Also, verify that the mount point for your media directory in MKVPriority is the same as the one used by Radarr/Sonarr.

Use Multiple Configs

MKVPriority supports multiple, tag-based configs that can be customized to match the tagging system used in Radarr/Sonarr. For example, you can create a separate config for anime by adding an anime tag in Radarr/Sonarr either manually or via auto-tagging. Then, append the ::anime tag to the config path in the MKVPriority arguments.

mkvpriority:
  image: ghcr.io/kennethsible/mkvpriority
  container_name: mkvpriority
  user: ${PUID}:${PGID}
  environment:
    WEBHOOK_PORT: "8080"
    MKVPRIORITY_ARGS: >
      --config /config/anime.toml::anime
      --archive /config/archive.db
  volumes:
    - /path/to/media:/media
    - /path/to/mkvpriority/config:/config
  ports:
    - 8080:8080
  restart: unless-stopped

Important

In Radarr/Sonarr, a given movie or show can have multiple tags. However, MKVPriority only uses the first tag in alphabetical order. Therefore, you may need to create new tags specifically for MKVPriority.

Cron Scheduler

You can use the built-in cron scheduler to periodically scan your media library and process MKV files. When paired with an archive database, MKVPriority will only process new files with each scan.

mkvpriority:
  image: ghcr.io/kennethsible/mkvpriority
  container_name: mkvpriority
  user: ${PUID}:${PGID}
  environment:
    TZ: "America/New_York"
    CRON_SCHEDULE: "0 0 * * *"
    CRON_TARGET_PATHS: /media
    MKVPRIORITY_ARGS: >
      --archive /config/archive.db
  volumes:
    - /path/to/media:/media
    - /path/to/mkvpriority/config:/config
  restart: unless-stopped

Note

MKVPriority supports non-standard macros for cron expressions, such as @daily and @hourly.

Extension Modules

MKVPriority supports user-defined extension modules for optional post-processing. This feature is designed to handle complex library edge cases, integrate your workflow with external tools, and provide an open-ended automation framework, such as automatically extracting embedded subtitles or dynamically restyling subtitle fonts.

Example: Subtitle Extractor

You can use the subtitle_extractor extension to extract embedded subtitles flagged as default or forced. This may result in smoother playback if your media player doesn't support certain subtitle formats. For example, if the player needs to transcode or burn in embedded subtitles, it must first demux and process the entire MKV container.

[subtitle_profiles.global]
extract_embedded_subtitles = true

Format:  {file_stem}.{language}.{default,forced}.{ext}
Example: Princess Mononoke (1997).eng.default.ass

Note

To avoid changing internal track flags and only use external subtitles, use the subtitle extractor with the --dry-run argument since subtitle extraction still runs during a dry run, which only prevents changes to the MKV container.

Example: Subtitle Converter

You can use the subtitle_converter extension to convert external subtitles between formats. Converting styled subtitles (.ass) to plain text (.srt) prevents server transcoding on devices with limited subtitle support. Conversely, converting plain text subtitles to stylized allows you to chain this module with the subtitle_restyler extension to apply advanced typography and consistent styling across your library.

[subtitle_profiles.global]
convert_external_subtitles = true
convert_target_format = "ass"
convert_remove_source = false

Example: Subtitle Renamer

You can use the subtitle_renamer extension to rename external sidecar subtitles to reflect their updated track states. When processing an MKV file, sidecar files are identified, normalized to ISO 639-2/T language codes, and scored alongside embedded tracks. If the track flags for an external subtitle change, this extension renames the file on disk to reflect its new flags, appending or stripping .default or .forced from the filename and standardizing the language code.

[subtitle_profiles.global]
rename_external_subtitles = true
rename_language_format = "3-letter"

Example: Subtitle Restyler

You can use the subtitle_restyler extension to restyle external subtitles by defining style overrides in your config file. Since this extension operates on external subtitles, it can be seamlessly chained with the subtitle extractor. To ensure this extension only restyles dialogue subtitles, it filters out styles that exceed calibrated thresholds for spatial, karaoke, and drawing tags. A complete list of restylable attributes can be found in the extension's Python script on GitHub.

[subtitle_styles]
Fontsize = 72
Bold = -1
Outline = 3.6
Shadow = 1.5

Format:  {file_stem}.{language}[.default][.forced][.{track_name}].{ext}
Example: Princess Mononoke (1997).jpn.default.commentary.ass

Note

The naming format for external subtitles follows the guidelines for both Jellyfin and Plex.

Example: Multiplexer

You can use the multiplexer extension to strip tracks with unwanted languages and reorder tracks by priority scores. Since remuxing involves unpacking and rewriting the container, these features are delegated to an extension module. To enable them, add the [multiplexer] section to your config file and include this extension in your arguments.

[audio_profiles.strip]
audio_mode = ["enabled"]

[subtitle_profiles.strip]
subtitle_mode = ["enabled"]

[multiplexer]
multiplex_container = true
remove_original_container = true
remove_external_subtitles = true
mkvmerge_arguments = []

strip_unscored_tracks = true
strip_audio_profile = "strip"
strip_subtitle_profile = "strip"

order_tracks_by_score = true
order_audio_profile = "default"
order_subtitle_profile = "dialogue"

Note

To avoid stripping tracks with your preferred languages, create profiles specifically for stripping tracks without any filters.

Creating Extensions

You can easily write your own post-processing scripts to handle custom logic.

1. Create a Python script (e.g., my_extension.py) inside any of the following:

   • current working directory (recommend for local development)
   • ~/.config/mkvpriority/extensions (recommended for pip)
   • /config/extensions (recommended for Docker)

2. Import the Extension class and implement the process_file method:

   class Extension(ABC):
       def __init__(self, extension_name: str | None = None):
           name = extension_name or self.__class__.__name__
           self.extension_logger = logging.getLogger(name)
   
       @abstractmethod
       def process_file(
           self,
           file_path: Path,
           video_tracks: list[Track],
           audio_tracks: list[Track],
           subtitle_tracks: list[Track],
           config: Config,
           database: Database | None = None,
           dry_run: bool = False,
       ) -> None:
           raise NotImplementedError

3. Use -i/--include with the script name (without the .py extension):

   mkvpriority -i my_extension

Note

Check the src/mkvpriority/extensions folder in the GitHub repository for example modules (see here).

CLI Usage

MKVToolNix must be installed on your system unless you are using the Docker image.

usage: mkvpriority [-h] [-c TOML_PATH[::TAG]] [-a DB_PATH] [-i MODULE_NAME] [-o KEY=VALUE] [-v] [-x] [-q] [-p] [-n] [-r] [INPUT_PATH[::TAG] ...]

positional arguments:
  INPUT_PATH[::TAG]     files or directories

options:
  -c, --config TOML_PATH[::TAG]
  -a, --archive DB_PATH
  -i, --include MODULE_NAME
                        include extension module
  -o, --override KEY=VALUE
                        override config settings
  -v, --verbose         inspect track metadata
  -x, --debug           print mkvtoolnix output
  -q, --quiet           suppress normal logging
  -p, --prune           prune database entries
  -n, --dry-run         simulate track changes
  -r, --restore         restore original flags

Python Package

To install the standalone CLI tool (without Docker), you can use pip:

pip install mkvpriority

To keep the CLI tool isolated from your environment, you can use uv:

uv tool install mkvpriority

Note

If you have uv installed, you can also run MKVPriority without installing using uvx mkvpriority.

Hardlinks Limitation

MKVPriority avoids remuxing by using mkvpropedit, but this still affects hardlinks since the metadata is modified. To avoid breaking hardlinks, use the subtitle extractor with the --dry-run argument (see here).