TwoTone is a versatile tool with various subtools for batch video file manipulations.

pip install -e .

This installs TwoTone in editable mode: the twotone command appears on PATH, and any code changes take effect immediately without reinstalling.

twotone <global options> <tool-name> <tool-specific options>

twotone --install-completion

Open a new terminal. Tab-completion now works:

twotone <TAB>           → concatenate, language_fix, melt, merge, ...
twotone --<TAB>         → --verbose, --quiet, --no-dry-run, ...
twotone merge --<TAB>   → merge-specific arguments

To remove: twotone --uninstall-completion

To see a list of global options, available tools, and their descriptions:

twotone --help

To get help for a specific tool:

twotone <tool-name> --help

Dry Run Mode: all tools run in a dry run mode by default (no files are being modified). Use the -r or --no-dry-run global option to perform actual operation. In live run mode most tools remove their input files after successful processing.
It is safe to stop execution with ctrl+c. All tools handle proper signal and will stop as soon as possible.
Working Directory: use -w or --working-dir to specify where temporary and working files are created. By default the directory is taken from the operating system's user data location for the application.

Data Safety: Always back up your data before using any tool, as source files may be deleted during processing.

The merge tool searches for movie and subtitle files and merges them into a single MKV file.

By default, subtitles are added without a language label. You can specify a language with the --language option.

For a full list of options:

twotone merge --help

The language_fix tool scans MKV files and fills missing language metadata for subtitle tracks by extracting them and running language detection. It can also infer audio track language from the track name (use --audio to enable; heuristic may be inaccurate).

twotone language_fix --help

The transcode tool transcodes videos using the x265 codec.

It takes a video directory as an input and determines the optimal CRF for each video by comparing the original and encoded versions. The script aims to achieve a quality level where SSIM ≈ 0.98 (by default).

For a full list of options:

twotone transcode --help

The concatenate tool looks for movie files which seem to be split into a few files (like CD1, CD2 etc) and glues them into one file.

twotone concatenate --help

The melt tool scans for duplicate video files and creates a single output using the best quality segments from each copy. Duplicates can be provided manually or taken from a Jellyfin server. Input files are kept intact by default.

twotone melt --help

The utilities tool groups smaller helpers. Currently it provides the scenes subtool for extracting frames from a video and saving them into per-scene folders.

twotone utilities scenes --help