How to use Gstreamer on TorizonCore
Introduction
TorizonCore platform features Docker runtime. Toradex provides Debian Docker images and deb packages that greatly eases the development process for embedded applications. In this article, we will show how you can run GStreamer in a container with TorizonCore.
The article Video Encoding and Playback (Linux) is not specific for Torizon, but some instructions may be applicable. For example, generic information about Wayland/Weston is provided.
The article How to use Cameras on Torizon aims to help you with instructions about the configuration and usage of cameras in the context of containers, using Gstreamer pipelines and Video4Linux2.
NXP provides GStreamer plugins to access the multimedia libraries using the i.MX SoC's hardware acceleration units. TorizonCore helps to reduce the complexity of the setup with Debian packages providing these HW optimized GStreamer plugins.
Typographic Conventions
Throughout the Toradex documentation, the following typographic conventions are used:
$ (dollar sign) Command in the host computer (e.g. your PC)
$ Command in your PC
$$ (double dollar sign) Command in a container in the host computer (e.g. your PC)
$$ Command inside a container in your PC
# (hashtag) Command in the target device/board (e.g. Linux terminal)
# Command in the target board, e.g. Colibri iMX6
## (double hashtag) Command inside a container in the target device (Torizon)
## Command inside a container in Torizon
> (greater-than sign) Command in the bootloader (e.g. U-Boot console)
> Command in the Bootloader
No symbol: Command output
$ Command waiting for output
Output
Prerequisites
- A Toradex's SoM with TorizonCore installed (To get instructions about how to install TorizonCore, see Quickstart Guide)
- Basic knowledge of Docker containers. To learn more about Docker, visit the developer's website. To learn the first steps with Docker usage and TorizonCore, check the Quickstart Guide
To take the best from this article and test things in practice, we recommend that you clone the torizon-samples repository to your computer:
$ cd ~
$ git clone --branch bullseye https://github.com/toradex/torizon-samples.git
Wayland + Weston
This example will run a pipeline that uses waylandsink GStreamer's plugin. This plugin runs on top of Wayland and Weston. It will be necessary to start 2 containers: One with the Weston image, and one with the application image, with Wayland support. Both will communicate through shared folders by bind mounting.
Dockerfile instructions
The implementation details will be explained in this session. See the Quickstart Guide with the instructions about how to compile the image on a host pc and pull the image onto the board. You can also scp
this file to the board and build it locally.
To build
Make sure you have configured your Build Environment for Torizon Containers
Now it's a good time to use torizon-samples repository:
$ cd ~/torizon-samples/gstreamer/bash/simple-pipeline
docker build --build-arg BASE_NAME=wayland-base-vivante --build-arg IMAGE_ARCH=linux/arm64/v8 -t <your-dockerhub-username>/gst_example .
$ docker build -t <your-dockerhub-username>/gst_example .
After the build, push the image to your Dockerhub account:
$ docker push <your-dockerhub-username>/gst_example
Details about the Dockerfile
In this section, you will go through some important snippets containing information about the Dockerfile.
Toradex Debian image - Wayland
Toradex provides a basic Wayland image in its Dockerhub page. If you are using an iMX8 (arm64v8 CPU) computer-on-module (COM) add torizon/wayland-base-vivante
to your image. Otherwise, add --platform=linux/arm torizon/wayland-base
. It contains the repository package. Remember to use a version of the container that is compatible with the version of TorizonCore you are using, from the container tag.
Choose from the tabs:
FROM --platform=linux/arm64/v8 torizon/wayland-base-vivante:2
FROM --platform=linux/arm/v7 torizon/wayland-base:2
Install GStreamer application and plugins
Install the required packages on the image with the following commands:
- Apalis iMX8 / Colibri iMX8X - Debian Bullseye Upstream Gstreamer Packages
- Apalis iMX8 / Colibri iMX8X - NXP Downstream Gstreamer Packages
- Apalis iMX6 / Colibri iMX6/iMX7
RUN apt update
RUN apt install -y libgstreamer1.0-0 gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-doc gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-qt5 gstreamer1.0-pulseaudio
VPU is not yet supported on Torizon.
The sample Dockerfile does not account for the instructions described in this section. You must modify it manually to apply the instructions.
# Toradex unstable feed that provides NXP's downstream Gstreamer(v1.16) packages
RUN echo "deb https://feeds.toradex.com/debian/snapshots/20220715T123302Z unstable main non-free" >> /etc/apt/sources.list
# Debian snapshot that contains gstreamer1.0-plugins-ugly and gstreamer1.0-libav v1.16
RUN echo "deb [check-valid-until=no] http://snapshot.debian.org/archive/debian/20200818T025233Z/ bullseye main" >> /etc/apt/sources.list
# Pin v1.16 for gstreamer1.0-plugins-ugly and gstreamer1.0-libav
RUN printf 'Package: gstreamer1.0-plugins-ugly\n\
Pin: version 1.16.2-2.1+b1\n\
Pin-Priority: 969\n\
\n\
Package: gstreamer1.0-libav\n\
Pin: version 1.16.2-2\n\
Pin-Priority: 969\n' > /etc/apt/preferences.d/version-pinned-packages
RUN apt update
RUN apt install -y libgstreamer1.0-0 gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-doc gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-qt5 gstreamer1.0-pulseaudio
NXP provides downstream fork for some Gstreamer packages. These include gstreamer1.0
, gst-plugins-base1.0
, gst-plugins-good1.0
and gst-plugins-bad1.0
. TorizonCore 5.0.0 is synced to an NXP BSP that contains v1.16 of these packages. TorizonCore 5.0.0 uses the main Debian Bullseye feed which provides v1.18 of these packages.
To be able to use v1.16 NXP Gstreamer packages we use the Toradex unstable feed.
There are other Gstreamer packages that do not have a donwstream NXP fork, such as gstreamer1.0-plugins-ugly
and gstreamer1.0-libav
. By default v1.18 of these packages would be downloaded from Debian Bullseye feed. gstreamer1.0-plugins-ugly
and gstreamer1.0-libav
v1.18 depend on libgstreamer-plugins-base1.0-0
(>= 1.18.0) and libgstreamer1.0-0
(>= 1.18.0) and this will cause a conflict with the v1.16 downstream packages. To avoid this we download the older v1.16 packages by adding an older Debian snapshot feed and version pinning these packages.
To find which Debian snapshot has a particular version of a package we can use buildd.debian.org and metasnap.d.n. For example in case of gstreamer1.0-plugins-ugly
, in the buildd log we see that the latest 1.16 version ever available in Debian was 1.16.2-2.1+b1
. Next, we use metasnap search to find the Debian snapshot where this version was available, in this case 20200818T025233Z
. Finally we add this snapshot to the list of feeds in /etc/apt/sources.list
and pin the version in /etc/apt/preferences.d/version-pinned-packages
. We can use the same workaround for any other packages that have a versioned dependency on the Gstreamer packages.
RUN apt update
RUN apt install -y libgstreamer1.0-0 gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-doc gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-pulseaudio
Test GStreamer
We will test GStreamer as entrypoint for our Dockerfile. A test source pattern will be output to a Wayland window. You can modify the pipeline for your needs
ENTRYPOINT gst-launch-1.0 videotestsrc ! videoconvert ! videoscale ! waylandsink sync=false
Docker-compose
After building the Dockerfile image above and pushing it to your Dockerhub, you can launch Weston and Wayland with docker-compose.
Select your architecture from the tabs:
Still on the torizon-samples/gstreamer/bash/simple-pipeline
directory, edit the docker-compose.arm64.yaml
file by filling the Weston image field with your image repository:
depends_on:
- weston
image: <your-username>/<your-image>
volumes:
After filling it, send it to your module using scp
:
$ scp docker-compose.arm64.yaml torizon@<your-ip>:/home/torizon
Now enter your module using SSH:
$ ssh torizon@<your-ip>
For more information about SSH, please refer to SSH on Linux.
Now you can launch by using the command:
# docker-compose -f docker-compose.arm64.yaml up
Still on the torizon-samples/gstreamer/bash/simple-pipeline
directory, edit the docker-compose.armhf.yaml
file by filling the Weston image field with your image repository:
depends_on:
- weston
image: <your-username>/<your-image>
volumes:
After filling it, send it to your module using scp
:
$ scp docker-compose.armhf.yaml torizon@<your-ip>:/home/torizon
Now enter your module using SSH:
$ ssh torizon@<your-ip>
For more information about SSH, please refer to SSH on Linux.
Now you can launch by using the command:
# docker-compose -f docker-compose.armhf.yaml up
Still on the torizon-samples/gstreamer/bash/simple-pipeline
directory, edit the docker-compose.colibri-imx7.yaml
file by filling the Weston image field with your image repository:
depends_on:
- weston
image: <your-username>/<your-image>
volumes:
After filling it, send it to your module using scp
:
$ scp docker-compose.colibri-imx7.yaml torizon@<your-ip>:/home/torizon
Now enter your module using SSH:
$ ssh torizon@<your-ip>
For more information about SSH, please refer to SSH on Linux.
Now you can launch by using the command:
# docker-compose -f docker-compose.colibri-imx7.yaml up