split wallpapers for 12 screen display

wallsplit.sh

#!/bin/bash
FORMAT=png
RESIZE_NAME="FULL"
RESIZE_OUTPUT=$RESIZE_NAME.$FORMAT
CUTOUTPUT="CUT"
SCREEN_WIDTH=$(( 1920))
SCREEN_HEIGHT=$((1081))

WIDTH=$((  $SCREEN_WIDTH  *4))
HEIGHT=$(( $SCREEN_HEIGHT *3))

# screen0 monitor 0 -> 02  n[1 ] =2
# screen0 monitor 1 -> 06  n[2 ] =6
# screen0 monitor 2 -> 10  n[3 ] =10
# screen0 monitor 3 -> 03  n[4 ] =3
# screen0 monitor 4 -> 07  n[5 ] =7
# screen0 monitor 5 -> 11  n[6 ] =11
# screen1 monitor 0 -> 00  n[7 ] =0
# screen1 monitor 1 -> 04  n[8 ] =4
# screen1 monitor 2 -> 08  n[9 ] =8
# screen1 monitor 3 -> 01  n[10] =1
# screen1 monitor 4 -> 05  n[11] =5
# screen1 monitor 5 -> 09  n[12] =9

mapping[0 ]="02"
mapping[1 ]="06"
mapping[2 ]="10"
mapping[3 ]="03"
mapping[4 ]="07"
mapping[5 ]="11"
mapping[6 ]="00"
mapping[7 ]="04"
mapping[8 ]="08"
mapping[9]="01"
mapping[10]="05"
mapping[11]="09"

for FILE in $*
do
  echo $FILE

  NAME=$(basename $FILE .jpg)

  echo $SCREEN_WIDTH $SCREEN_HEIGHT
  echo $WIDTH $HEIGHT

  OUTPUT_PATH="./"$NAME"/"
  #OUTPUT_PATH=./

  if [ -d $OUTPUT_PATH  ]
  then
    echo files already exist
  else
    mkdir $OUTPUT_PATH

    export MAGICK_THREAD_LIMIT=12
    convert $FILE \
      -resize $WIDTH"x"$HEIGHT^ \
      -gravity center \
      -crop $WIDTH"x"$HEIGHT+0+0 +repage \
      -crop $SCREEN_WIDTH"x"$SCREEN_HEIGHT +repage \
      $OUTPUT_PATH/$CUTOUTPUT"%02d."$FORMAT
  fi

  for n in {00..11}
  do
    n=${n#0}
    IMAGE=$(readlink -f $OUTPUT_PATH"CUT"${mapping[$n]}.$FORMAT)
    if [ $n -lt 6 ]
    then
      #xfconf-query -c xfce4-desktop -p /backdrop/screen1/monitor$(($n))/image-show -s true
      xfconf-query -c xfce4-desktop -p /backdrop/screen0/monitor$(($n))/image-path -s $IMAGE
    else
      #xfconf-query -c xfce4-desktop -p /backdrop/screen0/monitor$(($n-6))/image-show -s true
      xfconf-query -c xfce4-desktop -p /backdrop/screen1/monitor$(($n-6))/image-path -s $IMAGE
    fi
  done

done


xfdesktop --reload

this was tested on the wall