script to create mask file from scratch based on camera mask in frigate config file

snapshotMask.pl

#!/usr/bin/perl

use strict;
use warnings;

#   see: https://github.com/blakeblackshear/frigate

#   "snapshotMask.pl"  - simple script to allow creation of mask images for  frigate
#        files dropped in config directory

# makes a graphic mask you can use later  for transform like :
#      ${SRCDIRECTORY}/${event}.jpg is a full size frame from mp4 file at frame_time
#  composite -dissolve 70 -gravity center  ${SRCDIRECTORY}/${event}.jpg  /opt/frigate/config/hik193mask.bmp  -alpha Set  ${SRCDIRECTORY}/${event}.jpg


# needed imagemagick/stable, libyaml-libyaml-perl/stable and libimage-magick-perl/stable  for debian

use YAML::XS 'LoadFile';

#-------- modify to suit your environment ----[start]----------------------------------------------

my $CFGDIR="/opt/frigate/config";
my $CFGFILE="$CFGDIR/config.yml";

#-------- modify to suit your environment ----[end]------------------------------------------------

my %yaml = %{ LoadFile( $CFGFILE ) };
my @cameras = keys %{ $yaml{'cameras'} };

for my $c ( @cameras ){
    my $mask = $yaml{'cameras'}{$c}{'mask'};
       $mask =~ s/poly,// ;
    #print "$c uses  $mask\n";

    my $cmd =  qq[/usr/bin/convert -size 1920x1080 xc:black -fill white -stroke white -draw "polyline $mask"   ${CFGDIR}/${c}mask.gif ];
    `$cmd`;
       $cmd =  qq[/usr/bin/convert -size 1920x1080 xc:black -fill white -stroke white -draw "polyline $mask"   ${CFGDIR}/${c}mask.bmp ];
    `$cmd`;

}