Videoplayer in Kivy GUI not working. GStreamer problem?

Question

I'm trying to create a video player GUI for my Raspberry Pi (Raspbian Linux 9 Stretch) using python 2.7 and Kivy. The GUI was created, but the video refused to load or play.

I think the problem may be due to the installation of GStreamer within Kivy, as this is part of the output on the terminal, showing GStreamer isn't even an option.

[INFO] Video: Provider: null(['video_ffmpeg', 'video_ffpyplayer'] ignored)

Now, I know GStreamer is installed elsewhere, but Kivy evidently can't find it. I've tried uninstalling Kivy and reinstalling it using the Kivy supplied instructions, but it hasn't helped.

I think this might be the point during the installation where it goes wrong.

sudo apt-get install libsdl2-dev libsdl2-image-dev libsdl2-mixer-dev libsdl2-ttf-dev    pkg-config libgl1-mesa-dev libgles2-mesa-dev    python-setuptools libgstreamer1.0-dev git-core    gstreamer1.0-plugins-{bad,base,good,ugly}    gstreamer1.0-{omx,alsa} python-dev libmtdev-dev    xclip
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Note, selecting 'git' instead of 'git-core'
Package libgl1-mesa-dev is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package gstreamer1.0-plugins-ugly is not available, but is referred to by 
another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Unable to locate package libsdl2-dev
E: Unable to locate package libsdl2-image-dev
E: Unable to locate package libsdl2-mixer-dev
E: Unable to locate package libsdl2-ttf-dev
E: Package 'libgl1-mesa-dev' has no installation candidate
E: Unable to locate package libgstreamer1.0-dev
E: Couldn't find any package by glob 'libgstreamer1.0-dev'
E: Couldn't find any package by regex 'libgstreamer1.0-dev'
E: Package 'gstreamer1.0-plugins-ugly' has no installation candidate
E: Unable to locate package libmtdev-dev
E: Unable to locate package xclip

This is the sources list.

~ $ sudo cat /etc/apt/sources.list 

deb http://mirrordirector.raspbian.org/raspbian/ stretch main contrib non-free rpi

# Uncomment line below then 'apt-get update' to enable 'apt-get source'
#deb-src http://archive.raspbian.org/raspbian/ stretch main contrib non-free rpi

Any ideas on either how to point Kivy to GStreamer or how to install Kivy successfully so that I don't have this problem?

Please let me know if you would like anymore information.

Answer 1

You may have some repositories missing. The example below uses vi as a text editor, you may use any text editor you wish

1. sudo vi /etc/apt/sources.list
2. at the end of the deb line, after rpi, add firmware
3. on the next line, add deb http://archive.raspberrypi.org/debian/ stretch main ui
4. save, exit, then run sudo apt-get update, then run your installs again

Answer 2

As an alternative you may try to install ffpyplayer (ex pip3 install ffpyplayer). I also couldn't load any video, had the same Video: Provider: null as you, though for me no issue with the installation of gstreamer and its components. Now the log tells me:

[INFO   ] [VideoFFPy   ] Using ffpyplayer 4.3.2
[INFO   ] [Video       ] Provider: ffpyplayer(['video_ffmpeg'] ignored)

And the video loads.