Docker container for HandBrake

This project implements a Docker container for HandBrake.

The GUI of the application is accessed through a modern web browser (no installation or configuration needed on the client side) or via any VNC client.

A fully automated mode is also available: drop files into a watch folder and let HandBrake process them without any user interaction.

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HandBrake is a tool for converting video from nearly any format to a selection of modern, widely supported codecs.

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Table of Content

• Quick Start
• Usage
  • Environment Variables
    • Deployment Considerations
  • Data Volumes
  • Ports
  • Changing Parameters of a Running Container
• Docker Compose File
• Docker Image Versioning
• Docker Image Update
  • Synology
  • unRAID
• User/Group IDs
• Accessing the GUI
• Security
  • SSVNC
  • Certificates
  • VNC Password
• Reverse Proxy
  • Routing Based on Hostname
  • Routing Based on URL Path
• Shell Access
• Access to Optical Drive(s)
• Automatic Video Conversion
  • Multiple Watch Folders
  • Video Discs
  • Hooks
  • Temporary Conversion Directory
• Intel Quick Sync Video
  • unRAID
• Nightly Builds
• Debug Builds
  • unRAID
• Support or Contact

Quick Start

NOTE: The Docker command provided in this quick start is given as an example and parameters should be adjusted to your need.

Launch the HandBrake docker container with the following command:

docker run -d \
    --name=handbrake \
    -p 5800:5800 \
    -v /docker/appdata/handbrake:/config:rw \
    -v /home/user:/storage:ro \
    -v /home/user/HandBrake/watch:/watch:rw \
    -v /home/user/HandBrake/output:/output:rw \
    jlesage/handbrake

Where:

• /docker/appdata/handbrake: This is where the application stores its configuration, states, log and any files needing persistency.
• /home/user: This location contains files from your host that need to be accessible to the application.
• /home/user/HandBrake/watch: This is where videos to be automatically converted are located
• /home/user/HandBrake/output: This is where automatically converted video files are written.

Browse to http://your-host-ip:5800 to access the HandBrake GUI. Files from the host appear under the /storage folder in the container.

Usage

docker run [-d] \
    --name=handbrake \
    [-e <VARIABLE_NAME>=<VALUE>]... \
    [-v <HOST_DIR>:<CONTAINER_DIR>[:PERMISSIONS]]... \
    [-p <HOST_PORT>:<CONTAINER_PORT>]... \
    jlesage/handbrake

Parameter	Description
-d	Run the container in the background. If not set, the container runs in the foreground.
-e	Pass an environment variable to the container. See the Environment Variables section for more details.
-v	Set a volume mapping (allows to share a folder/file between the host and the container). See the Data Volumes section for more details.
-p	Set a network port mapping (exposes an internal container port to the host). See the Ports section for more details.

Environment Variables

To customize some properties of the container, the following environment variables can be passed via the -e parameter (one for each variable). Value of this parameter has the format <VARIABLE_NAME>=<VALUE>.

Variable	Description	Default
USER_ID	ID of the user the application runs as. See User/Group IDs to better understand when this should be set.	1000
GROUP_ID	ID of the group the application runs as. See User/Group IDs to better understand when this should be set.	1000
SUP_GROUP_IDS	Comma-separated list of supplementary group IDs of the application.	(no value)
UMASK	Mask that controls how file permissions are set for newly created files. The value of the mask is in octal notation. By default, the default umask value is 0022, meaning that newly created files are readable by everyone, but only writable by the owner. See the online umask calculator at http://wintelguy.com/umask-calc.pl.	0022
LANG	Set the locale, which defines the application's language, if supported. Format of the locale is language[_territory][.codeset], where language is an ISO 639 language code, territory is an ISO 3166 country code and codeset is a character set, like UTF-8. For example, Australian English using the UTF-8 encoding is en_AU.UTF-8.	en_US.UTF-8
TZ	TimeZone used by the container. Timezone can also be set by mapping /etc/localtime between the host and the container.	Etc/UTC
KEEP_APP_RUNNING	When set to 1, the application will be automatically restarted when it crashes or terminates.	0
APP_NICENESS	Priority at which the application should run. A niceness value of -20 is the highest priority and 19 is the lowest priority. The default niceness value is 0. NOTE: A negative niceness (priority increase) requires additional permissions. In this case, the container should be run with the docker option --cap-add=SYS_NICE.	0
INSTALL_PACKAGES	Space-separated list of packages to install during the startup of the container. Packages are installed from the repository of the Linux distribution this container is based on. ATTENTION: Container functionality can be affected when installing a package that overrides existing container files (e.g. binaries).	(no value)
CONTAINER_DEBUG	Set to 1 to enable debug logging.	0
DISPLAY_WIDTH	Width (in pixels) of the application's window.	1920
DISPLAY_HEIGHT	Height (in pixels) of the application's window.	1080
DARK_MODE	When set to 1, dark mode is enabled for the application.	0
SECURE_CONNECTION	When set to 1, an encrypted connection is used to access the application's GUI (either via a web browser or VNC client). See the Security section for more details.	0
SECURE_CONNECTION_VNC_METHOD	Method used to perform the secure VNC connection. Possible values are SSL or TLS. See the Security section for more details.	SSL
SECURE_CONNECTION_CERTS_CHECK_INTERVAL	Interval, in seconds, at which the system verifies if web or VNC certificates have changed. When a change is detected, the affected services are automatically restarted. A value of 0 disables the check.	60
WEB_LISTENING_PORT	Port used by the web server to serve the UI of the application. This port is used internally by the container and it is usually not required to be changed. By default, a container is created with the default bridge network, meaning that, to be accessible, each internal container port must be mapped to an external port (using the -p or --publish argument). However, if the container is created with another network type, changing the port used by the container might be useful to prevent conflict with other services/containers. NOTE: a value of -1 disables listening, meaning that the application's UI won't be accessible over HTTP/HTTPs.	5800
VNC_LISTENING_PORT	Port used by the VNC server to serve the UI of the application. This port is used internally by the container and it is usually not required to be changed. By default, a container is created with the default bridge network, meaning that, to be accessible, each internal container port must be mapped to an external port (using the -p or --publish argument). However, if the container is created with another network type, changing the port used by the container might be useful to prevent conflict with other services/containers. NOTE: a value of -1 disables listening, meaning that the application's UI won't be accessible over VNC.	5900
VNC_PASSWORD	Password needed to connect to the application's GUI. See the VNC Password section for more details.	(no value)
ENABLE_CJK_FONT	When set to 1, open-source computer font WenQuanYi Zen Hei is installed. This font contains a large range of Chinese/Japanese/Korean characters.	0
HANDBRAKE_DEBUG	Setting this to 1 enables HandBrake debug logging for both the GUI and the automatic video converter. For the latter, the increased verbosity is reflected in /config/log/hb/conversion.log (container path). For the GUI, log messages are sent to /config/log/hb/handbrake.debug.log (container path). NOTE: When enabled, a lot of information is generated and the log file will grow quickly. Make sure to enable this temporarily and only when needed.	0
HANDBRAKE_GUI	Setting this to 1 enables the HandBrake GUI, 0 disables it.	1
AUTOMATED_CONVERSION	Setting this to 1 enables the automatic video converter, 0 disables it.	1
AUTOMATED_CONVERSION_PRESET	HandBrake preset used by the automatic video converter. Identification of a preset must follow the format <CATEGORY>/<PRESET NAME>. See the Automatic Video Conversion section for more details.	General/Very Fast 1080p30
AUTOMATED_CONVERSION_FORMAT	Video container format used by the automatic video converter for output files. This is typically the video filename extension. See the Automatic Video Conversion section for more details.	mp4
AUTOMATED_CONVERSION_KEEP_SOURCE	When set to 0, a video that has been successfully converted is removed from the watch folder.	1
AUTOMATED_CONVERSION_VIDEO_FILE_EXTENSIONS	Space-separated list of file extensions to be considered as video files. By default, this list is empty, meaning that the automatic video converter will let HandBrake automatically detects if a file, no matter its extension, is a video or not (note that extensions defined by the AUTOMATED_CONVERSION_NON_VIDEO_FILE_EXTENSIONS environment variable are always considered as non-video files). Normally, this variable doesn't need to be set. Usage of this variable is useful when only specific video files need to converted.	(no value)
AUTOMATED_CONVERSION_NON_VIDEO_FILE_ACTION	When set to ignore, a non-video file found in the watch folder is ignored. If set to copy, a non-video file is copied as-is to the output folder.	ignore
AUTOMATED_CONVERSION_NON_VIDEO_FILE_EXTENSIONS	Space-separated list of file extensions to be considered as not being videos. Most non-video files are properly rejected by HandBrake. However, some files, like images, are convertible by HandBrake even if they are not video files.	jpg jpeg bmp png gif txt nfo
AUTOMATED_CONVERSION_OUTPUT_DIR	Root directory, inside the container, where converted videos should be written. NOTE: Make sure a volume mapping for this directory is defined when creating the container.	/output
AUTOMATED_CONVERSION_OUTPUT_SUBDIR	Subdirectory of the output folder into which converted videos should be written. By default, this variable is not set, meaning that videos are saved directly into /output/. If Home/Movies is set, converted videos will be written to /output/Home/Movies. Use the special value SAME_AS_SRC to use the same subfolder as the source. For example, if the video source file is /watch/Movies/mymovie.mkv, the converted video will be written to /output/Movies/.	(no value)
AUTOMATED_CONVERSION_OVERWRITE_OUTPUT	Setting this to 1 allows the final destination file to be overwritten if it already exists.	0
AUTOMATED_CONVERSION_SOURCE_STABLE_TIME	Time (in seconds) during which properties (e.g. size, time, etc) of a video file in the watch folder need to remain the same. This is to avoid processing a file that is being copied.	5
AUTOMATED_CONVERSION_SOURCE_MIN_DURATION	Minimum title duration (in seconds). Shorter titles will be ignored. This applies only to video disc sources (ISO file, VIDEO_TS folder or BDMV folder).	10
AUTOMATED_CONVERSION_SOURCE_MAIN_TITLE_DETECTION	Setting this to 1 enables HandBrake main feature title detection to try to guess and select the main title.	0
AUTOMATED_CONVERSION_CHECK_INTERVAL	Interval (in seconds) at which the automatic video converter checks for new files.	5
AUTOMATED_CONVERSION_MAX_WATCH_FOLDERS	Maximum number of watch folders handled by the automatic video converter.	5
AUTOMATED_CONVERSION_NO_GUI_PROGRESS	When set to 1, progress of videos converted by the automatic video converter is not shown in the HandBrake GUI.	0
AUTOMATED_CONVERSION_HANDBRAKE_CUSTOM_ARGS	Custom arguments to pass to HandBrake when performing a conversion.	(no value)
AUTOMATED_CONVERSION_INSTALL_PKGS	Space-separated list of Alpine Linux packages to install. This is useful when the automatic video converter's hooks require tools not available in the container image. See https://pkgs.alpinelinux.org for the list of available Alpine Linux packages.	(no value)
AUTOMATED_CONVERSION_USE_TRASH	When set to 1, the automatic video converter uses the trash directory. So when the automatic video converter is configured to not keep sources, it will move them to the trash directory (/trash inside the container) instead of deleting them.	0

Deployment Considerations

Many tools used to manage Docker containers extract environment variables defined by the Docker image and use them to create/deploy the container. For example, this is done by:

• The Docker application on Synology NAS
• The Container Station on QNAP NAS
• Portainer
• etc.

While this can be useful for the user to adjust the value of environment variables to fit its needs, it can also be confusing and dangerous to keep all of them.

A good practice is to set/keep only the variables that are needed for the container to behave as desired in a specific setup. If the value of variable is kept to its default value, it means that it can be removed. Keep in mind that all variables are optional, meaning that none of them is required for the container to start.

Removing environment variables that are not needed provides some advantages:

• Prevents keeping variables that are no longer used by the container. Over time, with image updates, some variables might be removed.
• Allows the Docker image to change/fix a default value. Again, with image updates, the default value of a variable might be changed to fix an issue, or to better support a new feature.
• Prevents changes to a variable that might affect the correct function of the container. Some undocumented variables, like PATH or ENV, are required to be exposed, but are not meant to be changed by users. However, container management tools still show these variables to users.
• There is a bug with the Container Station on QNAP and the Docker application on Synology, where an environment variable without value might not be allowed. This behavior is wrong: it's absolutely fine to have a variable without value. In fact, this container does have variables without value by default. Thus, removing unneeded variables is a good way to prevent deployment issue on these devices.

Data Volumes

The following table describes data volumes used by the container. The mappings are set via the -v parameter. Each mapping is specified with the following format: <HOST_DIR>:<CONTAINER_DIR>[:PERMISSIONS].

Container path	Permissions	Description
/config	rw	This is where the application stores its configuration, states, log and any files needing persistency.
/storage	ro	This location contains files from your host that need to be accessible to the application.
/watch	rw	This is where videos to be automatically converted are located
/output	rw	This is where automatically converted video files are written.
/trash	rw	When trash usage is enabled, this is where the automatic video converter moves converted files instead of deleting them.

Ports

Here is the list of ports used by the container.

When using the default bridge network, ports can be mapped to the host via the -p parameter (one per port mapping). Each mapping is defined with the following format: <HOST_PORT>:<CONTAINER_PORT>. The port number used inside the container might not be changeable, but you are free to use any port on the host side.

See the Docker Container Networking documentation for more details.

Port	Protocol	Mapping to host	Description
5800	TCP	Optional	Port to access the application's GUI via the web interface. Mapping to the host is optional if access through the web interface is not wanted. For a container not using the default bridge network, the port can be changed with the WEB_LISTENING_PORT environment variable.
5900	TCP	Optional	Port to access the application's GUI via the VNC protocol. Mapping to the host is optional if access through the VNC protocol is not wanted. For a container not using the default bridge network, the port can be changed with the VNC_LISTENING_PORT environment variable.

Changing Parameters of a Running Container

As can be seen, environment variables, volume and port mappings are all specified while creating the container.

The following steps describe the method used to add, remove or update parameter(s) of an existing container. The general idea is to destroy and re-create the container:

1. Stop the container (if it is running):

docker stop handbrake

2. Remove the container:

docker rm handbrake

3. Create/start the container using the docker run command, by adjusting parameters as needed.

NOTE: Since all application's data is saved under the /config container folder, destroying and re-creating a container is not a problem: nothing is lost and the application comes back with the same state (as long as the mapping of the /config folder remains the same).

Docker Compose File

Here is an example of a docker-compose.yml file that can be used with Docker Compose.

Make sure to adjust according to your needs. Note that only mandatory network ports are part of the example.

version: '3'
services:
  handbrake:
    image: jlesage/handbrake
    ports:
      - "5800:5800"
    volumes:
      - "/docker/appdata/handbrake:/config:rw"
      - "/home/user:/storage:ro"
      - "/home/user/HandBrake/watch:/watch:rw"
      - "/home/user/HandBrake/output:/output:rw"

Docker Image Versioning

Each release of a Docker image is versioned. Prior to october 2022, the semantic versioning was used as the versioning scheme.

Since then, versioning scheme changed to calendar versioning. The format used is YY.MM.SEQUENCE, where:

• YY is the zero-padded year (relative to year 2000).
• MM is the zero-padded month.
• SEQUENCE is the incremental release number within the month (first release is 1, second is 2, etc).

Docker Image Update

Because features are added, issues are fixed, or simply because a new version of the containerized application is integrated, the Docker image is regularly updated. Different methods can be used to update the Docker image.

The system used to run the container may have a built-in way to update containers. If so, this could be your primary way to update Docker images.

An other way is to have the image be automatically updated with Watchtower. Watchtower is a container-based solution for automating Docker image updates. This is a "set and forget" type of solution: once a new image is available, Watchtower will seamlessly perform the necessary steps to update the container.

Finally, the Docker image can be manually updated with these steps:

1. Fetch the latest image:

docker pull jlesage/handbrake

2. Stop the container:

docker stop handbrake

3. Remove the container:

docker rm handbrake

4. Create and start the container using the docker run command, with the the same parameters that were used when it was deployed initially.

Synology

For owners of a Synology NAS, the following steps can be used to update a container image.

1. Open the Docker application.
2. Click on Registry in the left pane.
3. In the search bar, type the name of the container (jlesage/handbrake).
4. Select the image, click Download and then choose the latest tag.
5. Wait for the download to complete. A notification will appear once done.
6. Click on Container in the left pane.
7. Select your HandBrake container.
8. Stop it by clicking Action->Stop.
9. Clear the container by clicking Action->Reset (or Action->Clear if you don't have the latest Docker application). This removes the container while keeping its configuration.
10. Start the container again by clicking Action->Start. NOTE: The container may temporarily disappear from the list while it is re-created.

unRAID

For unRAID, a container image can be updated by following these steps:

1. Select the Docker tab.
2. Click the Check for Updates button at the bottom of the page.
3. Click the update ready link of the container to be updated.

User/Group IDs

When using data volumes (-v flags), permissions issues can occur between the host and the container. For example, the user within the container may not exist on the host. This could prevent the host from properly accessing files and folders on the shared volume.

To avoid any problem, you can specify the user the application should run as.

This is done by passing the user ID and group ID to the container via the USER_ID and GROUP_ID environment variables.

To find the right IDs to use, issue the following command on the host, with the user owning the data volume on the host:

id <username>

Which gives an output like this one:

uid=1000(myuser) gid=1000(myuser) groups=1000(myuser),4(adm),24(cdrom),27(sudo),46(plugdev),113(lpadmin)

The value of uid (user ID) and gid (group ID) are the ones that you should be given the container.

Accessing the GUI

Assuming that container's ports are mapped to the same host's ports, the graphical interface of the application can be accessed via:

• A web browser:

http://<HOST IP ADDR>:5800

• Any VNC client:

<HOST IP ADDR>:5900

Security

By default, access to the application's GUI is done over an unencrypted connection (HTTP or VNC).

Secure connection can be enabled via the SECURE_CONNECTION environment variable. See the Environment Variables section for more details on how to set an environment variable.

When enabled, application's GUI is performed over an HTTPs connection when accessed with a browser. All HTTP accesses are automatically redirected to HTTPs.

When using a VNC client, the VNC connection is performed over SSL. Note that few VNC clients support this method. SSVNC is one of them.

SSVNC

SSVNC is a VNC viewer that adds encryption security to VNC connections.

While the Linux version of SSVNC works well, the Windows version has some issues. At the time of writing, the latest version 1.0.30 is not functional, as a connection fails with the following error:

ReadExact: Socket error while reading

However, for your convenience, an unofficial and working version is provided here:

https://github.com/jlesage/docker-baseimage-gui/raw/master/tools/ssvnc_windows_only-1.0.30-r1.zip

The only difference with the official package is that the bundled version of stunnel has been upgraded to version 5.49, which fixes the connection problems.

Certificates

Here are the certificate files needed by the container. By default, when they are missing, self-signed certificates are generated and used. All files have PEM encoded, x509 certificates.

Container Path	Purpose	Content
/config/certs/vnc-server.pem	VNC connection encryption.	VNC server's private key and certificate, bundled with any root and intermediate certificates.
/config/certs/web-privkey.pem	HTTPs connection encryption.	Web server's private key.
/config/certs/web-fullchain.pem	HTTPs connection encryption.	Web server's certificate, bundled with any root and intermediate certificates.

NOTE: To prevent any certificate validity warnings/errors from the browser or VNC client, make sure to supply your own valid certificates.

NOTE: Certificate files are monitored and relevant daemons are automatically restarted when changes are detected.

VNC Password

To restrict access to your application, a password can be specified. This can be done via two methods:

• By using the VNC_PASSWORD environment variable.
• By creating a .vncpass_clear file at the root of the /config volume. This file should contain the password in clear-text. During the container startup, content of the file is obfuscated and moved to .vncpass.

The level of security provided by the VNC password depends on two things:

• The type of communication channel (encrypted/unencrypted).
• How secure the access to the host is.

When using a VNC password, it is highly desirable to enable the secure connection to prevent sending the password in clear over an unencrypted channel.

ATTENTION: Password is limited to 8 characters. This limitation comes from the Remote Framebuffer Protocol RFC (see section 7.2.2). Any characters beyond the limit are ignored.

Reverse Proxy

The following sections contain NGINX configurations that need to be added in order to reverse proxy to this container.

A reverse proxy server can route HTTP requests based on the hostname or the URL path.

Routing Based on Hostname

In this scenario, each hostname is routed to a different application/container.

For example, let's say the reverse proxy server is running on the same machine as this container. The server would proxy all HTTP requests sent to handbrake.domain.tld to the container at 127.0.0.1:5800.

Here are the relevant configuration elements that would be added to the NGINX configuration:

map $http_upgrade $connection_upgrade {
	default upgrade;
	''      close;
}

upstream docker-handbrake {
	# If the reverse proxy server is not running on the same machine as the
	# Docker container, use the IP of the Docker host here.
	# Make sure to adjust the port according to how port 5800 of the
	# container has been mapped on the host.
	server 127.0.0.1:5800;
}

server {
	[...]

	server_name handbrake.domain.tld;

	location / {
	        proxy_pass http://docker-handbrake;
	}

	location /websockify {
		proxy_pass http://docker-handbrake;
		proxy_http_version 1.1;
		proxy_set_header Upgrade $http_upgrade;
		proxy_set_header Connection $connection_upgrade;
		proxy_read_timeout 86400;
	}
}

Routing Based on URL Path

In this scenario, the hostname is the same, but different URL paths are used to route to different applications/containers.

For example, let's say the reverse proxy server is running on the same machine as this container. The server would proxy all HTTP requests for server.domain.tld/handbrake to the container at 127.0.0.1:5800.

Here are the relevant configuration elements that would be added to the NGINX configuration:

map $http_upgrade $connection_upgrade {
	default upgrade;
	''      close;
}

upstream docker-handbrake {
	# If the reverse proxy server is not running on the same machine as the
	# Docker container, use the IP of the Docker host here.
	# Make sure to adjust the port according to how port 5800 of the
	# container has been mapped on the host.
	server 127.0.0.1:5800;
}

server {
	[...]

	location = /handbrake {return 301 $scheme://$http_host/handbrake/;}
	location /handbrake/ {
		proxy_pass http://docker-handbrake/;
		location /handbrake/websockify {
			proxy_pass http://docker-handbrake/websockify/;
			proxy_http_version 1.1;
			proxy_set_header Upgrade $http_upgrade;
			proxy_set_header Connection $connection_upgrade;
			proxy_read_timeout 86400;
		}
	}
}

Shell Access

To get shell access to the running container, execute the following command:

docker exec -ti CONTAINER sh

Where CONTAINER is the ID or the name of the container used during its creation.

Access to Optical Drive(s)

By default, a Docker container doesn't have access to host's devices. However, access to one or more device can be granted with the --device DEV parameter.

Optical drives usually have /dev/srX as device. For example, the first drive is /dev/sr0, the second /dev/sr1, and so on. To allow HandBrake to access the first drive, this parameter is needed:

--device /dev/sr0

To easily find devices of optical drives, start the container and look at its log for messages similar to these ones:

...
[cont-init.d] 54-check-optical-drive.sh: executing...
[cont-init.d] 54-check-optical-drive.sh: looking for usable optical drives...
[cont-init.d] 54-check-optical-drive.sh: found optical drive /dev/sr0, but it is not usable because is not exposed to the container.
[cont-init.d] 54-check-optical-drive.sh: no usable optical drive found.
[cont-init.d] 54-check-optical-drive.sh: exited 0.
...

Since HandBrake can decrypt DVD video discs, their conversion can be performed directly from the optical device. From the graphical interface, click the Open Source button and browse through the file system to find your optical drive device (e.g. /dev/sr0).

Automatic Video Conversion

This container has an automatic video converter built-in. This is useful to batch-convert videos without user interaction.

Basically, files copied to the /watch container folder are automatically converted by HandBrake to a pre-defined video format according to a pre-defined preset.

All configuration parameters of the automatic video converter are defined via environment variables. See the Environment Variables section for the list of available variables. The ones having their name starting with AUTOMATED_CONVERSION_ apply to the automatic video converter.

NOTE: A preset is identified by its category and its name.

NOTE: All default presets, along with personalized/custom ones, can be seen and edited with the HandBrake GUI.

NOTE: Converted videos are stored, by default, to the /output folder of the container.

NOTE: The status and progression of conversions performed by the automatic video converter can be seen from both the GUI and the container's log. Container's log can be obtained by executing the command docker logs handbrake, where handbrake is the name of the container. Also, full details about the conversion are stored in /config/log/hb/conversion.log (container path).

Multiple Watch Folders

If needed, additionnal watch folders can be used:

• /watch2
• /watch3
• /watch4
• /watch5
• etc.

This is useful for scenarios where videos need to be converted by different presets. For example, one could use a watch folder for movies and another watch folder for TV shows, both having different encoding quality requirements.

By default, additional watch folders inherits the same settings has the main one (/watch). A setting for a particular watch folder can be overriden by adding its index to the corresponding environment variable name.

For example, to set the HandBrake preset used to convert videos in /watch2, the environment variable AUTOMATED_CONVERSION_PRESET_2 is used. AUTOMATED_CONVERSION_PRESET_3 is used for /watch3, and so on.

All settings related to the automatic video converter (environment variables with name prefixed with AUTOMATED_CONVERSION_) can be overriden for each additional watch folder.

The maximum number of watch folders handled by the automatic video converter is defined by the AUTOMATED_CONVERSION_MAX_WATCH_FOLDERS environment variable.

NOTE: Each additional watch folder must be mapped to a folder on the host by adding a volume mapping during the creation of the container.

NOTE: Each output folder defined via the AUTOMATED_CONVERSION_OUTPUT_DIR environment variable must be mapped to a folder on the host by adding a volume mapping during the creation of the container.

Video Discs

The automatic video converter supports video discs, in the following format:

• ISO image file.
• DVD video disc folder containing the VIDEO_TS folder.
• Blu-ray video disc folder containing the BDMV folder.

Note that folder names are case sensitive. For example, video_ts, Video_Ts or Bdmv won't be treated as discs, but as normal directories.

When the source is a disc folder, the name of the converted video file will match to one of its folder. For example, /watch/MyMovie/VIDEO_TS will produce a video file with name MyMovie.mp4.

Video discs can have multiple titles (the main movie, previews, extras, etc). In a such case, each title is converted to its own file. These files have the suffix .title-XX, where XX is the title number. For example, if the file MyMovie.iso has 2 titles, the following files would be generated:

• MyMovie.title-1.mp4
• MyMovie.title-2.mp4

It is possible to ignore titles shorted than a specific amount of time. By default, only titles longer than 10 seconds are processed. This duration can be adjusted via the AUTOMATED_CONVERSION_SOURCE_MIN_DURATION environment variable. See the Environment Variables section for details about setting environment variables.

Hooks

Custom actions can be performed using hooks. Hooks are shell scripts executed by the automatic video converter.

NOTE: Hooks are always invoked via /bin/sh, ignoring any shebang the script may have.

Hooks are optional and by default, no one is defined. A hook is defined and executed when the script is found at a specific location.

The following table describe available hooks:

Container location	Description	Parameter(s)
/config/hooks/pre_conversion.sh	Hook executed before the beginning of a video conversion.	The first argument is the path of the converted video. The second argument is the path to the source file. Finally, the third argument is the name of the Handbrake preset that will be used to convert the video.
/config/hooks/post_conversion.sh	Hook executed when the conversion of a video file is terminated.	The first parameter is the status of the conversion. A value of 0 indicates that the conversion terminated successfuly. Any other value represent a failure. The second argument is the path to the converted video (the output). The third argument is the path to the source file. Finally, the fourth argument is the name of the Handbrake preset used to convert the video.
/config/post_watch_folder_processing.sh	Hook executed after all videos in the watch folder have been processed.	The path of the watch folder.

During the first start of the container, example hooks are installed in /config/hooks/. Example scripts have the suffix .example. For example, you can use /config/hooks/post_conversion.sh.example as a starting point.

NOTE: Keep in mind that this container has the minimal set of packages required to run HandBrake. This may limit actions that can be performed in hooks.

Temporary Conversion Directory

A video being converted is written in a hidden, temporary directory under the root of the output directory (/output by default). Once a conversion successfully terminates, the video file is moved to its final location.

This feature can be useful for scenarios where the output folder is monitored by another application: with proper configuration, one can make sure this application only "sees" the final, converted video file and not the transient versions.

If the monitoring application ignores hidden directories, then nothing special is required and the application should always see the final file.

However, if the monitoring application handles hidden directories, the automatic video converter should be configured with the AUTOMATED_CONVERSION_OUTPUT_SUBDIR environment variable sets to a subdirectory. The application can then be configured to monitor this subdirectory. For example, if AUTOMATED_CONVERSION_OUTPUT_SUBDIR is set to TV Shows and /output is mapped to /home/user/appvolumes/HandBrake on the host, /home/user/appvolumes/HandBrake/TV Shows should be monitored by the application.

Intel Quick Sync Video

Intel Quick Sync Video is Intel's brand for its dedicated video encoding and decoding hardware core. It is a technology that is capable of offloading video decoding and encoding task to the integrated GPU, thus saving the CPU usage to do other tasks. As a specialized hardware core on the processor die, Quick Sync offers a much more power efficient video processing which is much superior to video encoding on a CPU.

For HandBrake to be able to use hardware-accelerated encoding, the following are required:

• Have a compatible Intel processor. To determine if your CPU has the Quick Sync Video hardware, consult this list from the Intel Ark website. The model name of your processor is printed to the container's log during its startup. Look for a message like this:

  [cont-init.d] 95-check-qsv.sh: Processor: Intel(R) Core(TM) i7-2600 CPU @ 3.40GHz
  

• The Intel i915 graphic driver must be loaded on the host.
• The /dev/dri device must be exposed to the container. This is done by adding the --device /dev/dri parameter to the docker run command.

When Intel Quick Sync Video is properly enabled, HandBrake offers the following video encoder:

H.264 (Intel QSV)

If this encoder is not part of the list, something is wrong and looking at the container's log can give more details about the issue.

NOTE: In most cases, HandBrake can successfully access the /dev/dri device without changing anything on the host side. This is possible because the user under which the container is running is automatically added to the group owning the /dev/dri device. However, this method doesn't work if the device is owned by the group root. The problem can be fixed using one of the following methods:

• Running the container as root (USER_ID=0).
• Adding, on the host, read/write permissions for all to the /dev/dri device:

  sudo chmod a+wr /dev/dri/*
  

• Changing, on the host, the group owning the /dev/dri device. For example, to change the group to video:

  sudo chown root:video /dev/dri/*
  

unRAID

With recent versions of unRAID, the Intel i915 driver is already included in the distribution and is automatically loaded.

With older versions, the following lines might need to be added to /boot/config/go for the driver to be loaded during the startup of unRAID:

# Load the i915 driver.
modprobe i915

Nightly Builds

Nightly builds are based on the latest HandBrake development code. This means that they may have bugs, crashes and instabilities.

Nightly builds are available through Docker image tags. These tags have the following format:

nightly-<COMMIT_DATE>-<COMMIT_HASH>

Where:

• COMMIT_DATE is the date (in YYMMDDHHMMSS format) of the latest commit from the HandBrake Git repository.
• COMMIT_HASH is the short hash of the latest commit from the HandBrake Git repository.

The latest nightly build is available through the nightly-latest Docker image tag. The list of available tags are available on Docker Hub.

To use a Docker image tag, it has to be appended to the name of the Docker image during the creation of the container. Here is an example:

docker run [OPTIONS..] jlesage/handbrake:nightly-latest

Debug Builds

Debug builds can be used to better investigate problems that can occur with HandBrake. These builds have HandBrake compiled in debug mode and all symbols are kept.

The main use case of debug builds is debugging a crash. To do this, a core dump needs to be generated when HandBrake crashes. To make sure this core dump is properly generated, two things are required:

1. Core dumps must be enabled. This is done by setting the maximum size of cores via the --ulimit core=-1 parameter of the docker run command. A value of -1 mean "unlimited".

2. Location of the cores must be set. This can be done by executing the following command on the host:

   echo 'CORE_PATTERN' | sudo tee /proc/sys/kernel/core_pattern
   

   Where CORE_PATTERN is the template that defines the naming of core dump files. For example, to set the files in the configuration volume of the container (for easy retrieval from the host), use the pattern /config/core.%e.%t.

   NOTE: Because a core file contains the complete memory layout of an application, it is created with restrictive permissions. If another user other than the one used to run HandBrake needs to access the core file, permissions must be changed by executing chmod a+r CORE, where CORE is the path to the core file.

   NOTE: Since the core dump files pattern is shared between the host and the container, you may want to revert to the original pattern once done.

   NOTE: The current value of the pattern can be obtained by executing cat /proc/sys/kernel/core_pattern.

Debug builds are available by using Docker image tags with the debug suffix. Make sure to look at available tags on Docker Hub.

When creating the container, the tag needs to be appended to the name of the Docker image, like this:

docker run [OPTIONS..] jlesage/handbrake:v1.14.3-debug

unRAID

On systems running unRAID, the --ulimit core=-1 parameter can be added to the Extra Parameters field of the container settings.

Support or Contact

Having troubles with the container or have questions? Please create a new issue.

For other great Dockerized applications, see https://jlesage.github.io/docker-apps.