.. MediaGoblin Documentation
Written in 2011, 2012, 2014, 2015 by MediaGoblin contributors
To the extent possible under law, the author(s) have dedicated all
copyright and related and neighboring rights to this software to
the public domain worldwide. This software is distributed without
any warranty.
You should have received a copy of the CC0 Public Domain
Dedication along with this software. If not, see
.
.. _media-types-chapter:
====================
Media Types
====================
In the future, there will be all sorts of media types you can enable,
but in the meanwhile there are six additional media types: video, audio,
raw image, ASCII art, STL/3D models, PDF and Document.
First, you should probably read ":doc:`configuration`" to make sure
you know how to modify the MediaGoblin config file.
Enabling Media Types
====================
.. note::
Media types are now plugins
Media types are enabled in your MediaGoblin configuration file.
Most media types require **additional dependencies** that you will have to install. You
will find descriptions on how to satisfy the requirements of each media type
below.
To enable a media type, add the the media type under the ``[plugins]`` section
in you ``mediagoblin.ini``. For example, if your system supported image
and video media types, then it would look like this::
[plugins]
[[mediagoblin.media_types.image]]
[[mediagoblin.media_types.video]]
Note that after enabling new media types, you must run dbupdate. If you have
deployed MediaGoblin as an unprivileged user as described in
":doc:`production-deployments`", you'll first need to switch to this account::
sudo su mediagoblin --shell=/bin/bash
$ cd /srv/mediagoblin.example.org/mediagoblin
Now run dbupdate::
$ ./bin/gmg dbupdate
If you are running an active site, depending on your server
configuration, you may need to stop it first (and it's certainly a
good idea to restart it after the update).
How does MediaGoblin decide which media type to use for a file?
===============================================================
MediaGoblin has two methods for finding the right media type for an uploaded
file. One is based on the file extension of the uploaded file; every media type
maintains a list of supported file extensions. The second is based on a sniffing
handler, where every media type may inspect the uploaded file and tell if it
will accept it.
The file-extension-based approach is used before the sniffing-based approach,
if the file-extension-based approach finds a match, the sniffing-based approach
will be skipped as it uses far more processing power.
Configuring Media Types
=======================
Each media type has a ``config_spec.ini`` file with configurable
options and comments explaining their intended side effect. For
instance the ``video`` media type configuration can be found in
``mediagoblin/media_types/video/config_spec.ini``.
Audio
=====
To enable audio, install the GStreamer and python-gstreamer bindings (as well
as whatever GStreamer plugins you want, good/bad/ugly):
.. code-block:: bash
# Debian
sudo apt install python3-gst-1.0 gstreamer1.0-plugins-{base,bad,good,ugly} \
gstreamer1.0-libav python3-numpy
# Fedora
sudo dnf install gstreamer1-plugins-{base,bad-free,good,ugly-free} \
python3-numpy
Add ``[[mediagoblin.media_types.audio]]`` under the ``[plugins]`` section in your
``mediagoblin.ini`` and update MediaGoblin::
$ ./bin/gmg dbupdate
Restart MediaGoblin (and Celery if applicable). You should now be able to upload
and listen to audio files!
On production deployments, you will need to increase Nginx's
``client_max_body_size`` to allow larger files to be uploaded, or you'll get a
"413 Request Entity Too Large" error. See ":ref:`webserver-config`".
Production deployments will also need a separate process to transcode media in
the background. See ":ref:`systemd-service-files`" and
":ref:`background-media-processing`" sections of this manual.
Video
=====
To enable video, first install GStreamer and the python-gstreamer
bindings (as well as whatever GStreamer extensions you want,
good/bad/ugly):
.. code-block:: bash
# Debian
sudo apt install python3-gi gstreamer1.0-tools gir1.2-gstreamer-1.0 \
gir1.2-gst-plugins-base-1.0 gstreamer1.0-plugins-{base,bad,good,ugly} \
gstreamer1.0-libav python3-gst-1.0
# Fedora
sudo dnf install gstreamer1-plugins-{base,bad-free,good,ugly-free,openh264} \
python3-gobject python3-gstreamer1
Add ``[[mediagoblin.media_types.video]]`` under the ``[plugins]`` section in
your ``mediagoblin.ini`` and restart MediaGoblin.
Run::
$ ./bin/gmg dbupdate
Restart MediaGoblin (and Celery if applicable). Now you should be able to submit
videos, and MediaGoblin should transcode them.
On production deployments, you will need to increase Nginx's
``client_max_body_size`` to allow larger files to be uploaded, or you'll get a
"413 Request Entity Too Large" error. See ":ref:`webserver-config`".
Production deployments will also need a separate process to transcode media in
the background. To set that up, check out the ":doc:`deploying`" and
":doc:`production-deployments`" sections of this manual.
Configuring video
-----------------
``available_resolutions``
The list of resolutions that the video should be transcoded to, in the order
of transcoding. Choose among ``144p``, ``240p``, ``360p``, ``480p``, ``720p``
and ``1080p``. The default is ``480p,360p,720p``.
``default_resolution``
This is the initial resolution used by the video player. The default is
``480p``. For example::
[[mediagoblin.media_types.video]]
available_resolutions = 144p,240p
default_resolution = 144p
Raw image
=========
MediaGoblin can extract and display the JPEG preview from RAW images.
To enable raw image you need to install the Python library ``py3exiv2``. This
library is not currently available for Debian 11 but can be installed from the
Python Package Index after installing the build dependencies::
# Debian 11
sudo apt install libexiv2-dev libboost-python-devn
./bin/pip install py3pyexiv2
# Debian 12
sudo apt install python3-pyexiv2
Add ``[[mediagoblin.media_types.raw_image]]`` under the ``[plugins]``
section in your ``mediagoblin.ini`` and restart MediaGoblin.
Run::
./bin/gmg dbupdate
Restart MediaGoblin (and Celery if applicable). You should now be able to submit
raw images.
ASCII art
=========
To enable ASCII art support, first install the
`chardet `_
library, which is necessary for creating thumbnails of ASCII art::
$ ./bin/easy_install chardet
Next, modify your ``mediagoblin.ini``. In the ``[plugins]`` section, add
``[[mediagoblin.media_types.ascii]]``.
Run::
$ ./bin/gmg dbupdate
Restart MediaGoblin (and Celery if applicable). Now any .txt file you uploaded
will be processed as ASCII art!
STL / 3D model support
======================
To enable the "STL" 3D model support plugin, first make sure you have
a recent `Blender `_ installed and available on
your execution path. This feature has been tested with Blender 2.63.
It may work on some earlier versions, but that is not guaranteed (and
is surely not to work prior to Blender 2.5X).
Add ``[[mediagoblin.media_types.stl]]`` under the ``[plugins]`` section in your
``mediagoblin.ini`` and restart MediaGoblin.
Run::
$ ./bin/gmg dbupdate
Restart MediaGoblin (and Celery if applicable). You should now be able to upload
.obj and .stl files and MediaGoblin will be able to present them to your wide
audience of admirers!
PDF and Document
================
To enable the "PDF and Document" support plugin, you need:
1. pdftocairo and pdfinfo for PDF only support.
2. unoconv with headless support to support converting LibreOffice supported
documents as well, such as doc/ppt/xls/odf/odg/odp and more.
For the full list see mediagoblin/media_types/pdf/processing.py,
unoconv_supported.
All executables must be on your execution path.
To install this on Fedora::
sudo dnf install poppler-utils unoconv libreoffice-headless
Note: You can leave out unoconv and libreoffice-headless if you want only PDF
support. This will result in a much smaller list of dependencies.
pdf.js relies on git submodules, so be sure you have fetched them::
$ git submodule update --init
This feature has been tested on Fedora with:
poppler-utils-0.20.2-9.fc18.x86_64
unoconv-0.5-2.fc18.noarch
libreoffice-headless-3.6.5.2-8.fc18.x86_64
It may work on some earlier versions, but that is not guaranteed.
Add ``[[mediagoblin.media_types.pdf]]`` under the ``[plugins]`` section in your
``mediagoblin.ini`` and restart MediaGoblin.
Run::
$ ./bin/gmg dbupdate
Blog (HIGHLY EXPERIMENTAL)
==========================
MediaGoblin has a blog media type, which you might notice by looking
through the docs! However, it is *highly experimental*. We have not
security reviewed this, and it acts in a way that is not like normal
blogs (the blog posts are themselves media types!).
So you can play with this, but it is not necessarily recommended yet
for production use! :)