Development Repository

This is a development and test repo. Visit the production repository and branch for stable/production releases.

About

A Docker Mod for the LinuxServer.io Lidarr Docker container that uses ffmpeg and a script to automatically convert downloaded FLAC (or other format) files to MP3s. Default output quality is 320Kbps constant bit rate. Advanced options act as a light wrapper to ffmpeg, allowing conversion to any supported audio format, including AAC, AC3, Opus, and many others. A Batch Mode is also supported that allows usage outside of Lidarr.

NOTE: This mod supports Linux OSes only.

Development Container info:
Production Container info:

Installation

1. Pull the linuxserver/lidarr docker image from Docker Hub:
   docker pull linuxserver/lidarr:latest

2. Configure the Docker container with all the port, volume, and environment settings from the original container documentation here:
   linuxserver/lidarr

   1. Add a DOCKER_MODS environment variable to the docker run command, as follows:

      • Dev/test release: -e DOCKER_MODS=thecaptain989/lidarr-flac2mp3:latest
      • Stable release: -e DOCKER_MODS=linuxserver/mods:lidarr-flac2mp3

      Example Docker CLI Configuration

      docker run -d \
        --name=lidarr \
        -e PUID=1000 \
        -e PGID=1000 \
        -e TZ=America/Chicago \
        -e DOCKER_MODS=linuxserver/mods:lidarr-flac2mp3 \
        -p 8686:8686 \
        -v /path/to/appdata/config:/config \
        -v /path/to/music:/music \
        -v /path/to/downloads:/downloads \
        --restart unless-stopped \
        ghcr.io/linuxserver/lidarr

      Example Synology Configuration
      

   2. Start the container.

3. Configure a custom script from Lidarr's Settings > Connect screen and type the following in the Path field:
   /usr/local/bin/flac2mp3.sh

   Example
   

   This will use the defaults to create a 320Kbps MP3 file.

   For any other setting, you must either use one of the included wrapper scripts or create a custom script with the command line options you desire. See the Syntax section below.

Usage

New file(s) with will be placed in the same directory as the original FLAC file(s) (unless redirected with the --output option below) and have the same owner and permissions. Existing files with the same track name will be overwritten.

By default, if you've configured Lidarr's Recycle Bin path correctly, the original audio file will be moved there.
NOTE: If you have not configured the Recycle Bin, the original FLAC audio file(s) will be deleted and permanently lost. This behavior may be modifed with the --keep-file option.

Syntax

Note: The Arguments field for Custom Scripts was removed in Lidarr release v0.7.0.1347 due to security concerns. To support options with this version and later, a wrapper script can be manually created that will call flac2mp3.sh with the required arguments.

Command Line Options and Arguments

The script may be called with optional command line arguments.

The syntax for the command line is:
flac2mp3 [OPTIONS] [{-b|--bitrate} <bitrate> | {-v|--quality} <quality> | {-a|--advanced} "<options>" {-e|--extension} <extension>]
OR
flac2mp3 [OPTIONS] {-f|--file} <audio_file>

Where:

Option	Argument	Description
-d, --debug	[<level>]	Enables debug logging. Level is optional. Default of 1 (low). 2 includes API and FFmpeg output.
-b, --bitrate	<bitrate>	Sets the output quality in constant bits per second (CBR). Examples: 160k, 240k, 300000 Note: May not be specified with -v, -a, or -e.
-v, --quality	<quality>	Sets the output variable bit rate (VBR). Specify a value between 0 and 9, with 0 being the highest quality. See the FFmpeg MP3 Encoding Guide for more details. Note: May not be specified with -b, -a, or -e.
-a, --advanced	"<options>"	Advanced ffmpeg options. The specified options replace all script defaults and are sent directly to ffmpeg. The options value must be enclosed in quotes. See FFmpeg Options for details on valid options, and Guidelines for high quality audio encoding for suggested usage. Note: Requires the -e option to also be specified. May not be specified with -v or -b. WARNING: You must specify an audio codec (by including a -c:a <codec> ffmpeg option) or the resulting file will contain no audio! WARNING: Invalid options could result in script failure!
-e, --extension	<extension>	Sets the output file extension The extension may be prefixed by a dot (".") or not. Note: Requires the -a option to also be specified. May not be specified with -v or -b.
-f, --file	<audio_file>	If included, the script enters Batch Mode and converts the specified audio file. WARNING: Do not use this argument when called from Lidarr!
-o, --output	<directory>	Converted audio file(s) are saved to directory instead of being located in the same directory as the source audio file. The path will be created if it does not exist.
-k, --keep-file		Do not delete the source file or move it to the Lidarr Recycle bin. Note: This also disables triggering a Lidarr rescan after conversion.
-r, --regex	<regex>	Sets the regex used to match input files. Defaults is ".flac$".
--help		Display help and exit.
--version		Display version and exit.

If neither -b, -v, -a, or -e options are specified, the script will default to a constant 320Kbps MP3.

Technical notes on advanced options

The -a option effectively makes the script a generic wrapper for ffmpeg. FFmpeg is executed once per track with only the loglevel, input filename, and output filename being set. All other options are passed unparsed to the command line.

The exact format of the executed ffmpeg command is:

ffmpeg -loglevel error -i "input.flac" ${options} "output.${extension}"

Examples

-b 320k        # Output 320 kbit/s MP3 (non-VBR; same as default behavior)
-v 0           # Output variable bitrate MP3, VBR 220-260 kbit/s
-d -b 160k     # Enable debugging level 1, and output a 160 kbit/s MP3
-a "-c:v libtheora -map 0 -q:v 10 -c:a libopus -b:a 192k" -e .opus
               # Convert to Opus format, VBR 192 kbit/s, cover art, no overwright
-a "-vn -c:a libopus -b:a 192K" -e .opus -r '\.mp3$'
               # Convert .mp3 files to Opus format.
-a "-y -map 0 -c:a aac -b:a 240k -c:v copy" -e mp4
               # Convert to MP4 format, using AAC 240 kbit/s audio, cover art, overwrite file
--file "/path/to/audio/a-ha/Hunting High and Low/01 Take on Me.flac"
               # Batch Mode
               # Output 320kbit/s MP3
-o "/path/to/audio" -k
               # Place the converted file(s) in the specified directory and do not delete the original audio file(s).

Wrapper Scripts

To supply arguments to the script, one of the included wrapper scripts may be used or a custom wrapper script must be created.

Included Wrapper Scripts

For your convenience, several wrapper scripts are included in the /usr/local/bin/ directory.
You may use any of these scripts in place of the flac2mp3.sh mentioned in the Installation section above.

flac2mp3-debug.sh        # Enable debugging, level 1
flac2mp3-debug-2.sh      # Enable debugging, level 2
flac2mp3-vbr.sh          # Use variable bit rate MP3, quality 0
flac2opus.sh             # Convert to Opus format using .opus extension, 192 kbit/s, no covert art
flac2alac.sh             # Convert to Apple Lossless using an .m4a extension
flac2custom.sh           # Calls flac2mp3 with FLAC2CUSTOM_ARGS

flac2custom.sh uses arguments provided by FLAC2CUSTOM_ARGS environment variable. This allows advanced use case without having to provide a custom script. For instance, the following value would convert any .mp3 to opus :

-a "-vn -c:a libopus -b:a 192k" -e .opus -r '\.mp3$'

Make sure to correctly escape special characters when using this, in docker compose the previous command would need an extra $ :

environment:
  - FLAC2CUSTOM_ARGS=-a "-vn -c:a libopus -b:a 192k" -e .opus -r '\.mp3$$'

Example Wrapper Script

To configure an entry from the Examples section above, create and save a file called flac2mp3-custom.sh to /config containing the following text:

#!/bin/bash

. /usr/local/bin/flac2mp3.sh -d -b 160k

Make it executable:

chmod +x /config/flac2mp3-custom.sh

Then put /config/flac2mp3-custom.sh in the Path field in place of /usr/local/bin/flac2mp3.sh mentioned in the Installation section above.

Note: If you followed the Linuxserver.io recommendations when configuring your container, the /config directory will be mapped to an external storage location. It is therefore recommended to place custom scripts in the /config directory so they will survive container updates, but they may be placed anywhere that is accessible by Lidarr.

Triggers

The only events/notification triggers that are supported are On Release Import and On Upgrade

Batch Mode

Batch mode allows the script to be executed independently of Lidarr. It converts the file specified on the command line and ignores any environment variables that are normally expected to be set by the music management program.

Using this function, you can easily process all of your audio files in any subdirectory at once. See the Batch Example below.

Script Execution Differences in Batch Mode

Because the script is not called from within Lidarr, expect the following behavior while in Batch Mode:

• The file name must be specified on the command line
  (The -f option places the script in Batch Mode)
• Lidarr APIs are not called and its database is not updated.
  This may require a manual rescan of converted music files.
• Original audio files are deleted.
  The Recycle Bin function is not available. (Modifiable using the -k option.)

Batch Example

To convert all .FLAC files in the /music directory to Apple Lossless Audio Codec (ALAC), enter the following at the Linux command line:

find /music/ -type f -name "*.flac" | while read file; do /usr/local/bin/flac2mp3.sh -f "$file" -a "-c:a alac" -e m4a; done

Logs

A log file is created for the script activity called:

/config/logs/flac2mp3.txt

This log can be downloaded from Lidarr under System > Log Files

Log rotation is performed, with 5 log files of 1MB each kept, matching Lidarr's log retention.

NOTE: If debug logging is enabled with a level above 1, the log file can grow very large very quickly and is much more likely to be rotated. Do not leave high-level debug logging enabled permanently.

Credits

This would not be possible without the following:

Lidarr
LinuxServer.io Lidarr container
LinuxServer.io Docker Mods project
ffmpeg
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