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==On Screen Display==
==On Screen Display==
=== Show Keyboard commands ===
=== Show Keyboard commands ===
When showing software it's usefull for the students to see which keyboard shortcuts are pressed. This on screen display (OSD) can be installed like this:
When showing software it's usefull for the students to see which keyboard shortcuts are pressed. You can use screenkey, an on screen display (OSD) which should be installed like this: [https://gitlab.com/screenkey/screenkey/-/issues/111 (Don't install from repository)]
   sudo apt install screenkey
  git clone https://gitlab.com/screenkey/screenkey.git
will install the screenkey application. Run it from the taskbar:
  cd screenkey
   sudo ./setup.py install
will install the screenkey application. Run with screenkey


[[File:Screenkey.png]]
[[File:Screenkey.png]]
Make sure to check "Show modifier sequences only" otherwise everyone can read your password inputs...


=== Show Mouse Clicks ===
=== Show Mouse Clicks ===
There is a feature branch in the screenkey git which implements that, hopefully it will be merged into master once you read this.
== Using v4l2loopback to stream in and out of OBS ==
Load the v4l2loopback kernel module and create two devices.
    modprobe v4l2loopback devices=2 video_nr=10,9 card_label="OBS Output","Canon 5D" exclusive_caps=1
=== Stream Canon 5D via USB ===
    gphoto2 --stdout --capture-movie | gst-launch-1.0 fdsrc fd=0 ! decodebin name=dec ! queue ! videoconvert ! tee ! v4l2sink device=/dev/video9


== Stream Canon 5D via USB ==
[https://stackoverflow.com/questions/12278688/canon-dslr-video-loop-back-using-v4l2loopback-and-edsdk-liveview Source]


== Stream from OBS to a virtual camera source ==
=== Stream from OBS to a virtual camera source ===
We can't stream directly from OBS into Jitsi, BigBlueBitton, Google Meet, Skype, etc. For this wee need a virtual camera source.
We can't stream directly from OBS into Jitsi, BigBlueBitton, Google Meet, Skype, etc. So we are using v4l2loopback for this.
To install the v4l2sink for OBS follow these steps:


   sudo modprobe v4l2loopback devices=1 video_nr=10 card_label="OBS Cam" exclusive_caps=1
   apt install qtbase5-dev
  sudo apt install qtbase5-dev
   git clone --recursive https://github.com/obsproject/obs-studio.git
   git clone --recursive https://github.com/obsproject/obs-studio.git
   git clone https://github.com/CatxFish/obs-v4l2sink.git
   git clone https://github.com/CatxFish/obs-v4l2sink.git
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   cmake -DLIBOBS_INCLUDE_DIR="../../obs-studio/libobs" -DCMAKE_INSTALL_PREFIX=/usr ..
   cmake -DLIBOBS_INCLUDE_DIR="../../obs-studio/libobs" -DCMAKE_INSTALL_PREFIX=/usr ..
   make -j4
   make -j4
   sudo make install
   make install
 
In OBS, go to Menu → Tools → V4L2 Video Output
 
[[File:V4L2 Video Output.png]]


Source: https://srcco.de/posts/using-obs-studio-with-v4l2-for-google-hangouts-meet.html
In BigBlueButton (or any other videoconferencing service) Select the virtual "OBS Output" as a video source.


[https://srcco.de/posts/using-obs-studio-with-v4l2-for-google-hangouts-meet.html Source]





Latest revision as of 20:20, 31 May 2020

This page documents the setup of a Linux system for screencasting

On Screen Display

Show Keyboard commands

When showing software it's usefull for the students to see which keyboard shortcuts are pressed. You can use screenkey, an on screen display (OSD) which should be installed like this: (Don't install from repository)

 git clone https://gitlab.com/screenkey/screenkey.git
 cd screenkey
 sudo ./setup.py install

will install the screenkey application. Run with screenkey

Screenkey.png

Make sure to check "Show modifier sequences only" otherwise everyone can read your password inputs...

Show Mouse Clicks

There is a feature branch in the screenkey git which implements that, hopefully it will be merged into master once you read this.

Using v4l2loopback to stream in and out of OBS

Load the v4l2loopback kernel module and create two devices.

   modprobe v4l2loopback devices=2 video_nr=10,9 card_label="OBS Output","Canon 5D" exclusive_caps=1

Stream Canon 5D via USB

   gphoto2 --stdout --capture-movie | gst-launch-1.0 fdsrc fd=0 ! decodebin name=dec ! queue ! videoconvert ! tee ! v4l2sink device=/dev/video9

Source

Stream from OBS to a virtual camera source

We can't stream directly from OBS into Jitsi, BigBlueBitton, Google Meet, Skype, etc. So we are using v4l2loopback for this. To install the v4l2sink for OBS follow these steps:

  apt install qtbase5-dev
  git clone --recursive https://github.com/obsproject/obs-studio.git
  git clone https://github.com/CatxFish/obs-v4l2sink.git
  cd obs-v4l2sink
  mkdir build && cd build
  cmake -DLIBOBS_INCLUDE_DIR="../../obs-studio/libobs" -DCMAKE_INSTALL_PREFIX=/usr ..
  make -j4
  make install

In OBS, go to Menu → Tools → V4L2 Video Output

V4L2 Video Output.png

In BigBlueButton (or any other videoconferencing service) Select the virtual "OBS Output" as a video source.

Source


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