diff --git a/app/services/riiif/region/absolute.rb b/app/services/riiif/region/absolute.rb
index d12a738..dc49cc8 100644
--- a/app/services/riiif/region/absolute.rb
+++ b/app/services/riiif/region/absolute.rb
@@ -4,12 +4,17 @@ module Region
     class Absolute < Crop
       # TODO: only kakadu needs image_info. So there's potenial to optimize by
       # making image_info a proxy that fetches the info lazily when needed.
+      # @param [ImageInformation] image_info
+      # @param [String] x
+      # @param [String] y
+      # @param [String] width
+      # @param [String] height
       def initialize(image_info, x, y, width, height)
         @image_info = image_info
-        @offset_x = x
-        @offset_y = y
-        @width = width
-        @height = height
+        @offset_x = x.to_i
+        @offset_y = y.to_i
+        @width = width.to_i
+        @height = height.to_i
       end
 
       attr_reader :width, :height
diff --git a/app/services/riiif/size/absolute.rb b/app/services/riiif/size/absolute.rb
index 80c4971..66321a4 100644
--- a/app/services/riiif/size/absolute.rb
+++ b/app/services/riiif/size/absolute.rb
@@ -4,10 +4,13 @@ module Size
     # The aspect ratio of the returned image may be different than the extracted
     # region, resulting in a distorted image.
     class Absolute < Resize
+      # @param [ImageInformation] info
+      # @param [String] width
+      # @param [String] height
       def initialize(info, width, height)
         @image_info = info
-        @width = width
-        @height = height
+        @width = width.to_i
+        @height = height.to_i
       end
 
       # @return [String] a resize directive for imagemagick to use
diff --git a/spec/services/riiif/region/absolute_spec.rb b/spec/services/riiif/region/absolute_spec.rb
new file mode 100644
index 0000000..19e3b9d
--- /dev/null
+++ b/spec/services/riiif/region/absolute_spec.rb
@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+RSpec.describe Riiif::Region::Absolute do
+  let(:image_info) { double }
+
+  context 'when initialized with strings' do
+    let(:instance) { described_class.new(image_info, '5', '15', '50', '100') }
+
+    it 'casts height to an integer' do
+      expect(instance.height).to eq 100
+    end
+
+    it 'casts width to an integer' do
+      expect(instance.width).to eq 50
+    end
+  end
+end
diff --git a/spec/services/riiif/size/absolute_spec.rb b/spec/services/riiif/size/absolute_spec.rb
new file mode 100644
index 0000000..4c5ef03
--- /dev/null
+++ b/spec/services/riiif/size/absolute_spec.rb
@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+RSpec.describe Riiif::Size::Absolute do
+  let(:image_info) { double }
+
+  context 'when initialized with strings' do
+    let(:instance) { described_class.new(image_info, '50', '100') }
+
+    it 'casts height to an integer' do
+      expect(instance.height).to eq 100
+    end
+
+    it 'casts width to an integer' do
+      expect(instance.width).to eq 50
+    end
+  end
+end