Mac Forum / Programming / Perl / October 2004

My annoyance was not with the lack of naming, but with the fact that
screen shots come out at 300 dpi rather than being pixel accurate.

Eventually I gave up and did exactly as described, wrapped
screencapture and used our Keyboard Maestro to map the command-shift
keys to perl scripts instead.

The perl scripts each look something like this:

****
#!/usr/bin/perl -wT

use lib "/Users/peter/perl"
use warnings;
use strict;
#use diagnostics;

$ENV{PATH} = "/bin:/usr/bin";

use Peter::ScreenCapture;

Peter::ScreenCapture::screen_capture_selection_to_file();
****

And the ScreenCapture.pm follows.  A tricky part is detecting a
canceled capture (eg pressing the escape key)  because screencapture
does not give any indication.  It uses GraphicConverter to save the
file.  Currently, it mimics the systems "Picture #.tiff", but if you
change the AppleScript code for that to:

tell application "GraphicConverter"
    activate
    try
        save as window 1
    end try
end tell

then GC will prompt for a filename.

Enjoy,
   Peter.

****
package Peter::ScreenCapture;

use 5.006;
use strict;
use warnings;

require Exporter;

our @ISA = qw(Exporter);
our $VERSION = '1.00';

our @EXPORT_OK = qw(
    screen_capture_screen_to_file
    screen_capture_screen_to_clipboard
    screen_capture_selection_to_file
    screen_capture_selection_to_clipboard

    screen_capture_clipboard_to_file
);
our @EXPORT = qw(

);
our %EXPORT_TAGS = ( 'all' => [ @EXPORT_OK ] );

our $screencapture = '/usr/sbin/screencapture';

sub screen_capture_screen_to_file {
    if ( screen_capture_screen_to_clipboard() ) {
        screen_capture_clipboard_to_file();
    }
}

sub screen_capture_screen_to_clipboard {
    pbset( 'Screen Capture' );
    my $result = system( $screencapture, '-c' );
    return pbget() ne 'Screen Capture';
}

sub screen_capture_selection_to_file {
    if ( screen_capture_selection_to_clipboard() ) {
        screen_capture_clipboard_to_file();
    }
}

sub screen_capture_selection_to_clipboard {
    pbset( 'Screen Capture' );
    my $result = system( $screencapture, '-ci' );
    return pbget() ne 'Screen Capture';
}

sub pbset {
    my ( $what ) = @_;
    open( OUT, "|/usr/bin/pbcopy" ) or die;
    print OUT $what;
    close( OUT );
}

sub pbget {
    open( OUT, "/usr/bin/pbpaste|" ) or die;
    local undef $/;
    my $what = <OUT>;
    close( OUT );
    return $what;
}

sub screen_capture_clipboard_to_file {

    require Mac::OSA::Simple;

    my $n = 1;
    $ENV{HOME} =~ m!^(/\w+/\w+)$! or die "Bad Home Directory $ENV{HOME}";
    my $path = "$1/Desktop/Picture.tiff";
    while ( -e $path ) {
        $path =~ s!( ?\d*\.tiff)! $n.tiff! or die;
        $n++;
    }
  if ( open( my $fh, ">", $path ) ) {
    close( $fh );
  }

    Mac::OSA::Simple::applescript( <<EOM );
tell application "GraphicConverter"
    new image from clipboard
    save window 1 in alias (posix file "$path") as TIFF
    close window 1
end tell
EOM
}

1;
****

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