change size and quality of jpg/bmp pictures while keeping exifdata. The script makes a 'lightweight' version of original off-the-camera jpg pictures. The copy can be used for picture frames without taking up too much space.

exportjpg.pl

#!/usr/bin/perl
use Getopt::Long;
use strict;

my $src = $ENV{'PWD'};
my $dst = "/cygdrive/c/pictures/export/digital";
my $quality = 75;


sub usage {
    print STDERR "$0\n";
    print STDERR " [--verbose]\twrites everything that happens (2 levels)\n";
    print STDERR " [--dry]\tdo NOT execute any commands\n";
    print STDERR " [--quality]\treduce pictures to this jpg quality (default: $quali
ty)\n";
    print STDERR " [--dst]\talt. destination (default: $dst)\n";
    print STDERR " [--src]\talt. source (default: $src)\n\n";
    print STDERR " [--exif]\twill check destination files for exif data and move if 
missing\t";
    print STDERR "the command can be run without commands to reduce quality to $qual
ity\n";
    print STDERR "using current directory as source and default as destination\n\n";
}

my ($help, $verbose , $dry, $moveExifData);

GetOptions( 'help|?' => \$help,
            "verbose+" => \$verbose,
            "quality:$quality" => \$quality,
            "src:s" => \$src,
            "dst:s" => \$dst,
            "dry!" => \$dry,
	    "exif!" => \$moveExifData,
            );

if ($help) {
    usage();
    exit;
}

print "Reading from: $src".$/;
print "Exporting to: $dst".$/;

if ($moveExifData) {
    print "checking EXIF data in all exported files (and moving missing data from so
urce)\n";
    moveExifData($src);
}else{
    print "converting source files to ${quality}% quality and moving EXIF data\n";
    convert($src);; 
}

exit;

sub convert {
    my $dir = shift;
    local *DIR;

    makeDestinationDir($dir);
    print "$dir$/" or print "error - $!";
    
    opendir DIR, $dir or die "opendir $dir: $!";
    my $found = 0;
    while ($_ = readdir DIR) {
	next if /^\.{1,2}$/;
	#next if -f $path $_!~/JPG$/i || $_ !~ /BMP$/i;
	my $path = "$dir/$_";
	reduceJPGQuality($path) if -f $path && /JPG$/i;
	reduceBMPQuality($path) if -f $path && /BMP$/i;
	convert($path) if -d $path;
    }
    closedir DIR;
}
# http://www.mactricksandtips.com/2008/07/convert-images-using-terminal.html


sub moveExifData {
    my $dir = shift;
    local *DIR;

    makeDestinationDir($dir);
    print "$dir$/" or print "error - $!";
    
    opendir DIR, $dir or die "opendir $dir: $!";
    my $found = 0;
    while ($_ = readdir DIR) {
	next if /^\.{1,2}$/;
	my $path = "$dir/$_";

	if ( -f $path && /JPG$/i ) {
	    my $file = relativePath($path);
	    my $exiflines = `exiftool '$dst$file' | wc -l`;
	    chomp($exiflines);
	    if ( $exiflines <= 13 ) {
		moveEXIFdata($path);
	    } else {
		print " EXIF OK for $dst$file\n" if $verbose > 1;
	    }
	}
	moveExifData($path) if -d $path;
    }
    closedir DIR;
}

### *** TODO *** ###
# rsync -varuHpogt --filter='+ Picasa.ini' --filter='- *.*' /cygdrive/g/pictures/d40
x /cygdrive/c/pictures/export/digital/d40x
# rsync -varuHpogt --filter='+ Picasa.ini' --filter='- *.*' /cygdrive/g/pictures/dig
ital /cygdrive/c/pictures/export/digital
sub movePicasaData {
    my $dir = shift;
    local *DIR;

    makeDestinationDir($dir);
    print "$dir$/" or print "error - $!";
    
    opendir DIR, $dir or die "opendir $dir: $!";
    my $found = 0;
    while ($_ = readdir DIR) {
	next if /^\.{1,2}$/;
	my $path = "$dir/$_";

	if ( -f $path && /INI$/i ) {
	    my $file = relativePath($path);
	    # check date of $dst$file
	    # move the newest file
	    my $exiflines = `exiftool '$dst$file' | wc -l`;
	    chomp($exiflines);
	    if ( $exiflines <= 13 ) {
		movePicasadata($path);
	    } else {
		print " EXIF OK for $dst$file\n" if $verbose > 1;
	    }
	}
	movePicasaData($path) if -d $path;
    }
    closedir DIR;
}


sub makeDestinationDir {
    my $dir = relativePath(shift);
    if (! -e "$dst$dir" ) {
	print "mkdir -p $dst$dir".$/ if $verbose > 2;
	mkdir("$dst$dir", 0755) || `mkdir -m 0755 -p $dst$dir`;
	die "Can not mkdir $dst$dir: $!" if ! -e "$dst$dir";
    } else {
	print "$dst$dir exists$/" if $verbose > 2; 
    }
}

sub filename {
    my $file = shift;
    $file =~ s/.*\/(.+\.JPG)/\1/;
    return $file;
}

sub relativePath {
    my $relative = shift;
    $relative =~ s/$src//e;
    return $relative;
}

sub reduceJPGQuality {
    my $file = relativePath(shift);
    my $filename = filename($file);
    if ( ! -e "$dst$file" && $file =~ /JPG$/i ) {
	print " $filename quality reduced to $quality%$/";
	print "djpeg '$src$file' | cjpeg -verbose -quality $quality -outfile '$dst$f
ile'".$/ if $dry || $verbose > 2;
	`djpeg '$src$file' | cjpeg -verbose -quality $quality -outfile '$dst$file' 2
>/dev/null` if !$dry;	
	moveEXIFdata($file);
    } else {
	print "  $filename already converted$/" if $verbose > 1;
    }
}

sub reduceJPGsize {
    my $file = relativePath(shift);
    my $filename = filename($file);
    if ( ! -e "$dst$file" && $file =~ /JPG$/i ) {
	print " $filename quality reduced to $quality%$/";
	print "djpeg '$src$file' | cjpeg -verbose -quality $quality -outfile '$dst$f
ile'".$/ if $dry || $verbose > 2;
	`djpeg -fast -scale 1/8 '$src$file' | cjpeg -verbose -quality $quality -outf
ile '$dst$file' 2>/dev/null` if !$dry;	
	moveEXIFdata($file);
    } else {
	print "  $filename already converted$/" if $verbose > 1;
    }
}

sub moveEXIFdata {
    my $file = relativePath(shift);
    if ( -e "$dst$file" ) {
	print "  moving EXIF data$/";
	print "exiftool -TagsFromFile '$src$file' -all:all '$dst$file'$/" if $dry ||
 $verbose > 2;
#       exiftool -TagsFromFile src.jpg -all:all dst.jpg
#            Copy the values of all writable tags from "src.jpg" to "dst.jpg",
#            preserving the original tag groups.
	`exiftool -TagsFromFile '$src$file' -all:all '$dst$file'` if !$dry;
	unlink("$dst$file"."_original") if !$dry;
    }
}

sub reduceBMPQuality {
    my $file = relativePath(shift);
    my $filename = filename($file);
    my $jpgfile = $file; $jpgfile =~ s/BMP$/jpg/;
    if ( ! -e "$dst$jpgfile" && $file =~ /BMP$/i ) {
	print " $filename quality reduced to $quality%$/";
	print "cjpeg -verbose -quality $quality -outfile '$dst$file' '$src$file'".$/
 if $dry || $verbose > 2;
	`cjpeg -verbose -quality $quality -outfile '$dst$jpgfile' '$src$file' 2>/dev
/null` if !$dry;
    } else {
	print "  $filename already converted$/" if $verbose > 1;
    }
}


sub nef2jpg {
    my $file = relativePath(shift);
    if ( ! -e "$dst$file" && $file =~ /NEF$/i ) {
	print "\tcreating jpg file$/";
	print "\t\t$/";
# dcraw -c -w crw_0001.crw | cjpeg > crw_0001.jpeg
#	print "djpeg '$src$file' | cjpeg -verbose -quality $quality -outfile '$dst$f
ile'".$/ if $dry || $verbose;
#	`djpeg '$src$file' | cjpeg -verbose -quality $quality -outfile '$dst$file'` 
if !$dry;	
	moveEXIFdata($file);
    }
}

__END__;

=head1 NAME

exportjpg 

=head1 SYNOPSIS

Create a lightweight copy of large photo collections while maintaining EXIF data. Or
, how to anoy the family with endless slideshows in viewable quality.

=head1 DESCRIPTION

Normally, when working on pictures using C<djpeg>, C<djpeg> or similar, EXIF data is
 not copied to the resulting files. I found that anoying as I have all my pictues on
 my portable computer (limited space, always limited space) for easy and fast refere
nce. 

It is possible to check the existence of EXIF data in exported (by exportjpg) jpgs. 
During implementation of this program, I fucked up and did not know which exported f
iles contained EXIF data and which did not. The B<--exif> option checks the copies t
o determine the presence of a full set of EXIF data. If something is missing in the 
copy, the program will find the data in the original file.

=head1 USAGE

    exportjpg
    exportjpg --exif
    exportjpg --verbose --verbose --dry 

=head1 DEPENDENCIES

 djpeg - http://www.linuxcommand.org/man_pages/djpeg1.html
 cjpeg - http://www.linuxcommand.org/man_pages/cjpeg1.html
 exiftool - http://www.sno.phy.queensu.ca/~phil/exiftool/

Windows users will benefit greatly form B<Cygwin> http://www.cygwin.com/

=head1 OPTIONS

=over 4 

=item B<no options> - normal operation

cd to the directory containing the folders with pictures you want to export. Write C
<exportjpg>, wait.

=item B<--verbose> - verbose

several uses of B<verbose> is possible (and when I say 'several' I mean, two.)

=item B<--dry> - dry run
    
do not execute any time consuming commands (conversions or exif inspections)

=item B<--exif> - exif tester

if an execution of the command produced errors, it is possible to recheck the presen
ce of the exif data in the exported files with this option. When running in B<exif> 
mode, nothing else is done (no conversions)

=item B<--src> - source directory

If source directory is not the current directory.

=item B<--dst> - destination directory

To change the destination directory specified in the $dst variable on the fly.

=item B<--help> - help 

short option help

 [--verbose]    writes everything that happens (2 levels)
 [--dry]        do NOT execute any commands
 [--quality]    reduce pictures to this jpg quality (default: 75)
 [--dst]        alt. destination (default: $dst)
 [--src]        alt. source (default: $ENV{'PWD'})
 [--exif]       will check destination files for exif data and move 
                if missing 

the command can be run without commands to reduce quality to 75 using current direct
ory as source and default as destination
=back

=head TODO

Extend the program to accept RAW files as input using C<dcraw>.
Finish the BMP section (bmp2jpg) and add options for this

=head1 AUTHOR

Karsten Lang Pedersen <karsten@lang.dk>

=head1 COPYRIGHT

Copyright 2006 by Karsten Lang Pedersen (karsten@lang.dk). All rights reserved.

=cut