not cutting with ffmpeg but in kdenlive ('shot cut' could work as well) -- keyframe issue, especially with compressed video.
mjpeg would not have this problem (but is super heavy)


Setting up a pi autostart with video

http://automatist.org/2016/03/Setting_up_a_raspberry_pi_as_media_player.html

Shutting down


Encoding a video with subtitles, ffmpeg



Play a video with subtitles in mplayer

Put a video on a colored background


Cropping a video automatically/remove black bands

Dealing with pixel formats for raspberry


Connecting a non-behaving VGA screen


Change hdmi_group and hdmi_mode

Concatenating multiple videos

Inside the folder where the videos are, make a file called videos.txt with:



Flipping a video


Reversing a video


Removing a logo


Cutting a video with ffmpeg



Cutting a video with oggz chop



Finding lines at a certain length

[in a text-editor; in search & replace check/select 'regular expressions']


Backup/clone


or


Shutdown at a certain moment


or


https://www.raspberrypi.org/forums/viewtopic.php?p=828947https://superuser.com/questions/49289/what-is-the-bashrc-file#49292https://www.dexcript 
on https://bootterindustries.com/howto/run-a-program-on-your-raspberry-pi-at-startup/

switch off error messages for omxplayer


Stopping the Raspberry


Rotating the screen output


Making the system read-only


KAZAM shortcuts


Subtitles


Encoding a file with subtitles, vlc


OTHER TRICKS

reduce size of a pdf


Put different pdfs together

record conversation

pactl load-module module-loopback --> sound loopback
pactl unload-module module-loopback

now use any recorder

Other pdf tools on-line

https://smallpdf.com/
https://www.sejda.com/


Downloading a video (FB, ...)


Converting mediawiki to .odt


Converting epub to pdf

Converting webp to .png
dwebp example.webp -o example.png
Graphviz with pad

wget -O - https://pad.constantvzw.org/p/titipi.audit.NeON-graph/export/txt | sfdp -Tpng -o infrastructure.png

Reset printer

https://www.easyink.co.nz/support/hl-tn2345-toner-reset/

///////////////////////////

Need: 
6 pis installed with same raspbian version (CHECK does it matter what versions of hardware?)
6 micro sds
6 hdmi screens or vis cables/converters
6 + 6 powersockets
keyboard
mouse
bash script
cron script
timer/clock

Scenario:

Every day @ 21:00

Power on

Every day @ 05:00


Every day @ 06:00

Power down

installation https://www.raspberrypi.org/downloads/
cron https://www.raspberrypi.org/documentation/linux/usage/cron.md

sunrise times
http://www.sunrise-and-sunset.com/nl/sun/belgie/brussels

shutdown may be used to halt, power-off or reboot the machine.

The first argument may be a time string (which is usually "now").
Optionally, this may be followed by a wall message to be sent to all
logged-in users before going down.

The time string may either be in the format "hh:mm" for hour/minutes
specifying the time to execute the shutdown at, specified in 24h clock
format. Alternatively it may be in the syntax "+m" referring to the
specified number of minutes m from now.  "now" is an alias for "+0",
i.e. for triggering an immediate shutdown. If no time argument is
specified, "+1" is implied.