README.rdoc

In you erb template use one of the Djatoka::ViewHelpers : <%= djatoka_square_image_tag('info:lanl-repo/ds/5aa182c2-c092-4596-af6e-e95d2e263de3', {:scale => 250, :class => 'djatoka_image', :resolver => 'http://african.lanl.gov/adore-djatoka/resolver' }) %>

If you want to use the OpenLayers viewer, run the generator: script/generate djatoka

Make sure the included javascripts and jQuery are included in the head.

Edit config/initializers/djatoka.rb to the URL for your Djatoka image server resolver. And then restart your Rails server.

Use the following in you erb template: <%= djatoka_init_openlayers('http://memory.loc.gov/gmd/gmd433/g4330/g4330/np000066.jp2', 'map') %>

NOTE: Because the OpenLayers viewer uses Ajax, the Djatoka resolver URL must be at the same site (domain and port) as your application. The scripts also expect the resolver to remain at /adore-djatoka/resolver so maintain that path if you proxy Djatoka or dig into the javascript to change the path.

== Ruby versions

Tested with the following Ruby versions:

1.8.7-p249
1.8.7-p302
1.9.2-p0

== IIIF Support This gem can translate parameters from {International Image Interoperability Framework (IIIF)}[http://www-sul.stanford.edu/iiif/image-api/] requests into Djatoka requests. It follows the same pattern as creating a Djatoka::Region

=== IIIF Example

Create a resolver object with a URL.

resolver = Djatoka::Resolver.new('http://african.lanl.gov/adore-djatoka/resolver')

A known good identifier

identifier = 'info:lanl-repo/ds/5aa182c2-c092-4596-af6e-e95d2e263de3'

IIIF Image Request

Create a IiifRequest with the resolver and id

iiif_request = Djatoka::IiifRequest.new(resolver, identifier)

Set IIIF parameters and create a Djatoka::Region

Note: All IIIF parameters are required before creating a Djatoka::Region

djatoka_region = iiif_request.region('full').size('full').rotation('0').quality('default').format('jpg').djatoka_region

Use the Djatoka::Region as normal

djatoka_region.url

IIIF Info Request (Metadata)

(See the 2.0 Info Request spec)}[http://iiif.io/api/image/2.0/#information-request]

First, create a Djatoka::Metadata object and perform the request to the server for metadata.

metadata = resolver.metadata(identifier).perform

Create a IIIF Info json response string

Set values to optional fields by passing in a block and calling setters on the yielded Mash

json = metadata.to_iiif_json do |opts| opts.tile_width = 512 # tile_* can be string or int opts.tile_height = "512" opts.compliance_level = 1 opts.formats = ["jpg", "png"] opts.qualities = ["default", "gray"] end

== Commandline

There is also a little commandline utility for outputting the OpenURL.

$ djatoka_url --resolver http://african.lanl.gov/adore-djatoka/resolver --rftid info:lanl-repo/ds/5aa182c2-c092-4596-af6e-e95d2e263de3 --scale 300 --square
{"region"=>"0,874,421,421", "scale"=>"300", "level"=>"3"}
http://african.lanl.gov/adore-djatoka/resolver?svc.level=3&url_ver=Z39.88-2004&svc.region=0%2C874%2C421%2C421&svc.scale=300&rft_id=info%3Alanl-repo%2Fds%2F5aa182c2-c092-4596-af6e-e95d2e263de3&svc_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajpeg2000&svc_id=info%3Alanl-repo%2Fsvc%2FgetRegion

$ djatoka_url --resolver http://african.lanl.gov/adore-djatoka/resolver --rftid info:lanl-repo/ds/5aa182c2-c092-4596-af6e-e95d2e263de3 --smallbox --browser chromium-browser

$ djatoka_url --help

== TODO

Testing the view helpers.
View more examples of images where the dwtLevels differ from the Djatoka levels.

== Authors

Jason Ronallo, Willy Mene