A simple script to take screenshot and archive it.

record.sh

#!/bin/bash

# Requirement: 
# Linux: xdotool + convert(imagemagik) + flameshot
# Mac:  xdotool + imagemagick
# Print out each commands and bail if there is an error
set -ex

CODELOC=$HOME/.sanscreenie
SCRLOC="$CODELOC/screenshots"
ARCV="$CODELOC/archive"
mkdir -p $SCRLOC
mkdir -p $ARCV
TEMPHASH="$CODELOC/mouseloc.md5"
TEMPFILE="$SCRLOC/temp.jpg"
# Make sure this file exists
touch $TEMPHASH

function takescreenshotmac {
  numberofdisplay=$(/usr/sbin/system_profiler SPDisplaysDataType | /usr/bin/grep Resolution: | /usr/bin/wc -l)
  for n in `seq 1 $numberofdisplay`
  do
    /usr/sbin/screencapture -x -D $n -t jpg $TEMPFILE
    convert $TEMPFILE  -strip -depth 5 -quality 50 +dither -colors 8 $SCRLOC/`date +"%Y-%m-%d_%H-%M-%S"`-D$n.png
  done
  # screencapture -t jpg test.jpg
}

function takescreenshotlinux {
  # Get the current mouse location hash
  CURRENTHASH=`xdotool getmouselocation | md5sum`
  
  # Get the previous mouse location hash
  PREVIOUSHASH=$(cat $TEMPHASH)
  
  # If mouse moved, take a screenshot
  if [[ "$CURRENTHASH" != "$PREVIOUSHASH"  ]]; then
    echo "$CURRENTHASH" > $TEMPHASH
    echo "Mouse moved since last screenshot - Saving a new one!"
    # Take high resolution screenshot - Cost a lot of diskspace
    # flameshot full -p $SCRLOC
    # Take low resolution screenshot :) 
    flameshot full -r | convert png:-  +dither -colors 8 $SCRLOC/`date +"%Y-%m-%d_%H-%M-%S"`.png
  fi
 
}

## Create gpg encrypted archive
function archive {
  ## Create encrypted achive if there screenshots taken
  if [[ $1 == "" ]];then
    echo "Please provide a recipient email for gpg encrypt function"
    exit
  fi
  cd $SCRLOC
  n=$(find . -type f -name "*.png" | wc -l)
  if (( $n > 0 )); then
  echo $n
    ls *
    tar -c *.png |  /usr/local/bin/gpg --output $ARCV/`date +'%s'`.tar.gpg --encrypt --recipient  $1 
    ## Delete all screenshots
    rm $SCRLOC/*.png
    rm $SCRLOC/*.jpg
  fi
# To decrypt the screnshot archive, we use the following command:
# gpg --decrypt  1605006952.tar.gpg  | tar xv
}


function help {
   echo "$0 <task> <args>"
   echo "Tasks: "
   compgen -A function | egrep -v 'cleanup|callmeusage' |cat -n
}

# To quickly use this script to record screen every 5 seconds:
# while [ 1 ]; do screenrecord schedulerun; sleep 5; done
function schedulerun {
  if [ -f /tmp/screenrec ]; then
    if [ "$(uname)" == "Darwin" ]; then
	    takescreenshotmac
    else
	    takescreenshotlinux
    fi
  fi 
}


# execute the function and arguments pass to this script.
# If nothing provided, run help function
${@:-help}

./record.sh takescreenshot will take screenshot if the mouse has moved since its last position
./record.sh archive your@email.address will gpg encrypts screenshot files using your public key and thus only you can decrypt it later.

This script is useful in various occasions, for example, when you work on an incident and need to record your actions or have a way for you to go back later to backtrack your steps when writing an incident report, you can run this script using linux watch command to take screenshot every second to take note. The archive script should be run every day or more frequent, depends on how paranoid you are leaving screenshots of your activities on your own machine :)