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RRWO / Image-JPEG-Size-0.03 / lib / Image / JPEG / Size.pm 

            

              
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package Image::JPEG::Size;
use strict;
use warnings;
our $VERSION = '0.03';
use Carp qw(croak);
use XSLoader;
XSLoader::load(__PACKAGE__, $VERSION);
sub new {
    my $class = shift;
    my %args = @_ == 1 && ref($_[0]) eq 'HASH' ? %{ $_[0] }
             : @_ % 2 == 0 ? @_
             :    croak("$class\->new takes a hash list or hash ref");
    return $class->_new(\%args);
}
sub DESTROY { $_[0]->_destroy }
sub file_dimensions_hash {
    my ($w, $h) = shift->file_dimensions(@_);
    return width => $w, height => $h;
}
1;
__END__
=pod
=encoding utf-8
=head1 NAME
Image::JPEG::Size - find the size of JPEG images
=head1 SYNOPSIS
    use Image::JPEG::Size;
    my $jpeg_sizer = Image::JPEG::Size->new;
    my ($width, $height) = $jpeg_sizer->file_dimensions($filename);
=head1 DESCRIPTION
This module uses libjpeg to rapidly determine the size of one or more JPEG
images.
=head1 CONSTRUCTOR
First create an instance of the class:
    my $jpeg_sizer = Image::JPEG::Size->new;
The constructor initialises internal libjpeg structures; if that fails, an
exception is thrown.
The constructor takes attributes as either a hash reference or a listified
hash. Unknown attributes are ignored. The following attributes are understood:
=over 4
=item C<error>
Specifies the action to take on encountering a non-recoverable error in an
image; see L</ERROR HANDLING>. Defaults to C<fatal>.
=item C<warning>
Specifies the action to take on encountering a recoverable error in an image;
see L</ERROR HANDLING>. Defaults to C<warn>.
=back
=head1 METHODS
=head2 C<file_dimensions>
You can repeatedly call C<file_dimensions> in list context to find the width
and height of your JPEG images:
    my ($width, $height) = $jpeg_sizer->file_dimensions($filename);
For now, the JPEG images must be supplied as a filename.
=head2 C<file_dimensions_hash>
In some cases, you may prefer to get the image dimensions as a hash. The
C<file_dimensions_hash> takes a single filename argument, and returns
a listified hash with keys C<width> and C<height>.
=head1 ERROR HANDLING
By default, recoverable errors in the image are reported using Perl's warning
mechanism, and non-recoverable errors cause an exception to be thrown. However,
this behaviour can be changed when creating an Image::JPEG::Size instance. The
options are:
=over 4
=item C<fatal>
Throw an exception with information about the error, and stop processing this
image immediately.
=item C<warn>
Emit a Perl warning with information about the error. If the error is
non-recoverable, image processing stops immediately, and its dimensions are
reported as 0×0 pixels.
=item C<quiet>
Suppress the error entirely. If the error is non-recoverable, image processing
stops immediately, and its dimensions are reported as 0×0 pixels.
=back
=head1 AUTHOR
Aaron Crane, E<lt>arc@cpan.orgE<gt>
Currently maintained by Robert Rothenberg E<lt>rrwo@cpan.orgE<gt>.
The initial development of this module was sponsored by Science Photo Library
L<https://www.sciencephoto.com/>.
=head1 COPYRIGHT
Copyright 2017, 2025 Aaron Crane.
=head1 LICENSE
This library is free software and may be distributed under the same terms
as perl itself. See L<http://dev.perl.org/licenses/>.
=cut