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# Convert Plugin

The `convert` plugin lets you convert parts of your collection to a directory of your choice, transcoding audio and embedding album art along the way. It can transcode to and from any format using a configurable command line. Optionally an m3u playlist file containing all the converted files can be saved to the destination path.

## Installation

To use the `convert` plugin, first enable it in your configuration (see Using Plugins). By default, the plugin depends on FFmpeg to transcode the audio, so you might want to install it.

## Usage

To convert a part of your collection, run `beet convert QUERY`. The command will transcode all the files matching the query to the destination directory given by the `-d` (`--dest`) option or the `dest` configuration. The path layout mirrors that of your library, but it may be customized through the `paths` configuration. Files that have been previously converted—and thus already exist in the destination directory—will be skipped.

The plugin uses a command-line program to transcode the audio. With the `-f` (`--format`) option you can choose the transcoding command and customize the available commands through the configuration.

Unless the `-y` (`--yes`) flag is set, the command will list all the items to be converted and ask for your confirmation.

The `-a` (or `--album`) option causes the command to match albums instead of tracks.

By default, the command places converted files into the destination directory and leaves your library pristine. To instead back up your original files into the destination directory and keep converted files in your library, use the `-k` (or `--keep-new`) option.

To test your configuration without taking any actions, use the `--pretend` flag. The plugin will print out the commands it will run instead of executing them.

By default, files that do not need to be transcoded will be copied to their destination. Passing the `-l` (`--link`) flag creates symbolic links instead, passing `-H` (`--hardlink`) creates hard links. Note that album art embedding is disabled for files that are linked. Refer to the `link` and `hardlink` options below.

The `-F` (or `--force`) option forces transcoding even when safety options such as `no_convert`, `never_convert_lossy_files`, or `max_bitrate` would normally cause a file to be copied or skipped instead. This can be combined with `--format` to explicitly transcode lossy inputs to a chosen target format. The default value for this flag comes from the `force` configuration option.

The `-m` (or `--playlist`) option enables the plugin to create an m3u8 playlist file in the destination folder given by the `-d` (`--dest`) option or the `dest` configuration. The path to the playlist file can either be absolute or relative to the `dest` directory. The contents will always be relative paths to media files, which tries to ensure compatibility when read from external drives or on computers other than the one used for the conversion. There is one caveat though: A list generated on Unix/macOS can’t be read on Windows and vice versa. Depending on the beets user’s settings a generated playlist potentially could contain unicode characters. This is supported, playlists are written in M3U8 format.

The `-r` (or `--refresh`) option allows to refresh the converted files if the originals ones are modified. It instructs the plugin to compare the timestamps of the latest modification for both the originals and the converted files. If an original file is newer than a converted file, the converted file will be removed from the filesystem, and the original file will be converted once again.

## Configuration

To configure the plugin, make a `convert:` section in your configuration file. The available options are:

- auto: Import transcoded versions of your files automatically during imports. With this option enabled, the importer will transcode all (in the default configuration) non-MP3 files over the maximum bitrate before adding them to your library. Default: `no`.

- auto_keep: Convert your files automatically on import to dest but import the non transcoded version. It uses the default format you have defined in your config file. Default: `no`. This import behavior is fixed and is not affected by `keep_new`.

  Note

  You probably want to use only one of the `auto` and `auto_keep` options, not both. Enabling both will convert your files twice on import, which you probably don’t want.

- tmpdir: The directory where temporary files will be stored during import. Default: none (system default),

- copy_album_art: Copy album art when copying or transcoding albums matched using the `-a` option. Default: `no`.

- album_art_maxwidth: Downscale album art if it’s too big. The resize operation reduces image width to at most `maxwidth` pixels while preserving the aspect ratio. The specified image size will apply to both embedded album art and external image files.

- dest: The directory where the files will be converted (or copied) to. Default: none.

- embed: Embed album art in converted items. Default: `yes`.

- id3v23: Can be used to override the global `id3v23` option. Default: `inherit`.

- write_metadata: Can be used to disable writing metadata to converted files. Default: `true`.

- max_bitrate: By default, the plugin does not transcode files that are already in the destination format. This option instead also transcodes files with high bitrates, even if they are already in the same format as the output. Note that this does not guarantee that all converted files will have a lower bitrate—that depends on the encoder and its configuration. Default: none. This option is ignored when `force` is enabled (via config or `--force`).

- no_convert: Does not transcode items matching the query string provided (see Queries). For example, to not convert AAC or WMA formats, you can use `format:AAC, format:WMA` or `path::\.(m4a|wma)$`. If you only want to transcode WMA format, you can use a negative query, e.g., `^path::\.(wma)$`, to not convert any other format except WMA. This option is ignored when `force` is enabled (via config or `--force`).

- never_convert_lossy_files: Cross-conversions between lossy codecs—such as mp3, ogg vorbis, etc.—makes little sense as they will decrease quality even further. If set to `yes`, lossy files are always copied. Default: `no`. When `never_convert_lossy_files` is enabled, lossy source files (for example MP3 or Ogg Vorbis) are normally not transcoded and are instead copied or linked as-is. To explicitly transcode lossy files in spite of this, use the `force` setting (from config or `--force`) with the `convert` command (optionally together with `--format` to choose a target format)

- force: Force transcoding by default. When enabled, items are transcoded even when `no_convert`, `never_convert_lossy_files`, or `max_bitrate` would otherwise copy or skip them. This applies to both `beet convert` and automatic conversion during import (`auto` and `auto_keep`). Default: `false`.

- keep_new: Enable `--keep-new` behavior by default for `beet convert`. Converted files stay in your library and originals are moved to the external destination. This option applies only to `beet convert` and does not change `auto_keep` import semantics. Default: `false`.

- paths: The directory structure and naming scheme for the converted files. Uses the same format as the top-level `paths` section (see Path Format Configuration). Default: Reuse your top-level path format settings.

- quiet: Prevent the plugin from announcing every file it processes. Default: `false`.

- threads: The number of threads to use for parallel encoding. By default, the plugin will detect the number of processors available and use them all.

- link: By default, files that do not need to be transcoded will be copied to their destination. This option creates symbolic links instead. Note that options such as `embed` that modify the output files after the transcoding step will cause the original files to be modified as well if `link` is enabled. For this reason, album-art embedding is disabled for files that are linked. Default: `false`.

- hardlink: This options works similar to `link`, but it creates hard links instead of symlinks. This option overrides `link`. Only works when converting to a directory on the same filesystem as the library. Default: `false`.

- delete_originals: Transcoded files will be copied or moved to their destination, depending on the import configuration. By default, the original files are not modified by the plugin. This option deletes the original files after the transcoding step has completed. Default: `false`.

- playlist: The name of a playlist file that should be written on each run of the plugin. A relative file path (e.g `playlists/mylist.m3u8`) is allowed as well. The final destination of the playlist file will always be relative to the destination path (`dest`, `--dest`, `-d`). This configuration is overridden by the `-m` (`--playlist`) command line option. Default: none.

- refresh: Refresh the converted files if needed by re-converting modified original files. This configuration is overridden by the `-r` (`--refresh`) command line option. Default: `false`.

You can also configure the format to use for transcoding (see the next section):

- format: The name of the format to transcode to when none is specified on the command line. Default: `mp3`.

- formats: A set of formats and associated command lines for transcoding each.

### Configuring the transcoding command

You can customize the transcoding command through the `formats` map and select a command with the `--format` command-line option or the `format` configuration.

    convert:
        format: speex
        formats:
            speex:
                command: ffmpeg -i $source -y -acodec speex $dest
                extension: spx
            wav: ffmpeg -i $source -y -acodec pcm_s16le $dest

In this example `beet convert` will use the speex command by default. To convert the audio to `wav`, run `beet convert -f wav`. This will also use the format key (`wav`) as the file extension.

Each entry in the `formats` map consists of a key (the name of the format) as well as the command and optionally the file extension. `extension` is the filename extension to be used for newly transcoded files. If only the command is given as a string or the extension is not provided, the file extension defaults to the format’s name. `command` is the command to use to transcode audio. The tokens `$source` and `$dest` in the command are replaced with the paths to the existing and new file.

The plugin in comes with default commands for the most common audio formats: `mp3`, `alac`, `flac`, `aac`, `opus`, `ogg`, `wma`. For details have a look at the output of `beet config -d`.

For a one-command-fits-all solution use the `convert.command` and `convert.extension` options. If these are set, the formats are ignored and the given command is used for all conversions.

    convert:
        command: ffmpeg -i $source -y -vn -aq 2 $dest
        extension: mp3

### Gapless MP3 encoding

While FFmpeg cannot produce “gapless” MP3s by itself, you can create them by using LAME directly. Use a shell script like this to pipe the output of FFmpeg into the LAME tool:

    #!/bin/sh
    ffmpeg -i "$1" -f wav - | lame -V 2 --noreplaygain - "$2"

Then configure the `convert` plugin to use the script:

    convert:
        command: /path/to/script.sh $source $dest
        extension: mp3

This strategy configures FFmpeg to produce a WAV file with an accurate length header for LAME to use. Using `--noreplaygain` disables gain analysis; you can use the ReplayGain Plugin to do this analysis. See the LAME documentation and the HydrogenAudio wiki for other LAME configuration options and a thorough discussion of MP3 encoding.