BPL::Derivatives
Modified version of samvera/hydra-derivatives to be backwards compatible with Fedora Commons 3.8.1.
Installation
Add this line to your application's Gemfile:
gem 'bpl-derivatives'And then execute:
$ bundle
Or install it yourself as:
$ gem install bpl-derivatives
Usage
Currently there is no implementation of the ActiveTranscoder features. Also the Audio and Video derivatives have not been thoroughly tested either.
The main purpose of this was to make newer versions of hydra-derivatives backwards compatible with Fedora 3.8.1 datastreams. Rather than fork this from Samvera I determined that the BPL's use case was out of their current scope and instead implemented this version. Also be aware this has not been tested with ActiveFedora > 9
Given an ActiveFedora Model Like So
class MyObject < ActiveFedora::Base
has_file_datastream 'masterFile' ..
endYou can now add the following
class MyObject < ActiveFedora::Base
include BPL::Derivatives
...
...
def generate_derivatives
case self.masterFile.mimeType
when 'image/tif'
derivatize runner: :jpeg2k_image, source_datastream: "masterFile", outputs: [ {recipe: :default, dsid: 'myJp2kDatastream' } ]
derivatize runner: :image, source_datastream: "masterFile", outputs: [
{ label: :thumb, size: "x800>", dsid: 'my800pxThumbDS', format: 'jpg' },
{ label: :thumb, size: "300x300>", dsid: 'my300pxThumbDS', format: 'jpg' }
]
when 'application/pdf'
derivatize runner: :image, source_datastream: "masterFile", outputs: [{label: :thumb, size: "300x300>", dsid: 'my300pxThumbDD', format: 'jpg', quality: 100, density: 200, layer: 0}] #Recommend passing in quality denisty and layer 0 for pdfs Contributing
Bug reports and pull requests are welcome on GitHub at https://github.com/boston-library/bpl-derivatives.
License
The gem is available as open source under the terms of the MIT License.