NAME
    Image::JPEG::Size - find the size of JPEG images

SYNOPSIS
        use Image::JPEG::Size;

        my $jpeg_sizer = Image::JPEG::Size->new;
        my ($width, $height) = $jpeg_sizer->file_dimensions($filename);

DESCRIPTION
    This module uses libjpeg to rapidly determine the size of one or more
    JPEG images.

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:

    "error"
        Specifies the action to take on encountering a non-recoverable error
        in an image; see "ERROR HANDLING". Defaults to "fatal".

    "warning"
        Specifies the action to take on encountering a recoverable error in
        an image; see "ERROR HANDLING". Defaults to "warn".

METHODS
  "file_dimensions"
    You can repeatedly call "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.

  "file_dimensions_hash"
    In some cases, you may prefer to get the image dimensions as a hash. The
    "file_dimensions_hash" takes a single filename argument, and returns a
    listified hash with keys "width" and "height".

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:

    "fatal"
        Throw an exception with information about the error, and stop
        processing this image immediately.

    "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.

    "quiet"
        Suppress the error entirely. If the error is non-recoverable, image
        processing stops immediately, and its dimensions are reported as 0×0
        pixels.

AUTHOR
    Aaron Crane, <arc@cpan.org>

    The initial development of this module was sponsored by Science Photo
    Library <https://www.sciencephoto.com/>.

COPYRIGHT
    Copyright 2017 Aaron Crane.

LICENSE
    This library is free software and may be distributed under the same
    terms as perl itself. See <http://dev.perl.org/licenses/>.

