Author image Jakob Voß
and 2 contributors

NAME

IIIF::Magick - transform image with IIIF Image API Request using Image Magick

SYNOPSIS

    use IIIF::Magick qw(info convert);

    my $info = info($file, profile => "level0", id => "...") ;
    
    convert( $request, $file, "target.png" );

DESCRIPTION

This module maps IIIF ImageAPI request parameters to ImageMagick command line arguments. See i3f (command line) and IIIF::ImageAPI (web service) for applications that make use of it.

REQUIREMENTS

Function info and convert require ImageMagick to be installed. Converting to PDF and/or WebP may not be enabled by default. For instance at Ubuntu Linux remove the line

  <policy domain="coder" rights="none" pattern="PDF" />

fro /etc/ImageMagick*/policy.xml and install WebP support via:

  sudo apt-get install webp libwebp-dev

FUNCTIONS

available

Returns whether ImageMagick is available.

info( $file [, id => $id ] [, profile => $profile ] )

Returns image information object with fields @context, type, profile, width, and height. Fields id and profile must be added for full IIIF compliance.

convert( $request, $file, $output [, @args ] )

Convert an image file as specified with a IIIF::Request into an output file. Returns true on success. Additional arguments are prepended to the call of ImageMagick's convert.

Requires at least ImageMagick 6.9.

convert_command( $request, $file, $output [, @args ] )

Get a shell-quoted command to convert an image with a IIIF::Request.

convert_args( $request )

Get the list of command line arguments to convert to transform an image file as specified via a IIIF::Request.

LIMITATIONS

The upscale option of size parameter is ignored: size ^max will not upscale the image as the resulting size depends on additional variables maxWidth, maxHeight, maxArea.

The IIIF Image API Request is not validated before processing. Sizes larger than the selected region will therefore always result in an upscaled image. Use method canonical of IIIF::Request to filter out such invalid requests.