Raspberry PI 4; 4" 480x800 viewfinder; Webcam mirrored on HDMI-2

_.local_share_applications_mirror-1080p-mplayer.desktop

[Desktop Entry]
Encoding=UTF-8
Version=1.0
Name[en_US]=Mirror Webcam 1080p
Type=Application
Exec=/home/pi/mirror-1080p-mplayer.sh
Categories=AudioVideo;Player

_.local_share_applications_mirror-720p-mplayer.desktop

[Desktop Entry]
Encoding=UTF-8
Version=1.0
Name[en_US]=Mirror Webcam 720p
Type=Application
Exec=/home/pi/mirror-720p-mplayer.sh
Categories=AudioVideo;Player

_usr_share_dispsetup.sh

#!/bin/sh
if ! grep -q 'Raspberry Pi' /proc/device-tree/model \
	|| (grep -q okay /proc/device-tree/soc/v3d@7ec00000/status 2> /dev/null \
	|| grep -q okay /proc/device-tree/soc/firmwarekms@7e600000/status 2> /dev/null \
	|| grep -q okay /proc/device-tree/v3dbus/v3d@7ec04000/status 2> /dev/null) ; then
	if xrandr --output HDMI-2 --mode 1280x720 --primary \
		  --output HDMI-1 --mode 480x800 --scale-from 768x1280 --rotate left --same-as HDMI-2 \
		  --dryrun ; then
		xrandr --output HDMI-2 --mode 1280x720 --primary \
		       --output HDMI-1 --mode 480x800 --scale-from 768x1280 --rotate left --same-as HDMI-2
	elif xrandr --output HDMI-2 --mode 1280x720 --rate 60.00 --pos 0x0 --rotate normal \
		  --output HDMI-1 --primary --mode FIXED_MODE --rate 59.78 --pos 0x0 --rotate left \
		  --dryrun ; then 
		xrandr --output HDMI-2 --mode 1280x720 --rate 60.00 --pos 0x0 --rotate normal \
		       --output HDMI-1 --primary --mode FIXED_MODE --rate 59.78 --pos 0x0 --rotate left
	fi
fi
if [ -e /usr/share/tssetup.sh ] ; then
. /usr/share/tssetup.sh
fi
exit 0

mirror-1080p-mplayer.sh

#!/bin/bash

echo setting HDMI-2 to 1080p
echo setting HDMI-1 to mirror and scale to 1080p
xrandr --fb 1920x1080 \
       --output HDMI-2 --mode 1920x1080 --primary \
       --output HDMI-1 --mode 480x800 --scale-from 1152x1920 --rotate left --same-as HDMI-2

sleep 1

echo displaying webcam at 1080p full-screen
mplayer tv:// -tv driver=v4l2:width=1920:height=1080:device=/dev/video0 -fs

mirror-720p-mplayer.sh

#!/bin/bash

echo setting HDMI-2 to 720p
echo setting HDMI-1 to mirror and scale to 720p
xrandr --fb 1280x720 \
       --output HDMI-2 --mode 1280x720 --primary \
       --output HDMI-1 --mode 480x800 --scale-from 768x1280 --rotate left --same-as HDMI-2

sleep 1

echo displaying webcam at 720p full-screen
mplayer tv:// -tv driver=v4l2:width=1280:height=720:device=/dev/video0 -fs