diff --git a/app/models/upload.rb b/app/models/upload.rb
index 802be437e74..bf3d4155154 100644
--- a/app/models/upload.rb
+++ b/app/models/upload.rb
@@ -128,9 +128,7 @@ class Upload < ActiveRecord::Base
       end
 
     self.width, self.height = size = FastImage.new(path).size
-    if !size.blank?
-      self.thumbnail_width, self.thumbnail_height = ImageSizer.resize(*size)
-    end
+    self.thumbnail_width, self.thumbnail_height = ImageSizer.resize(*size)
     nil
   end
 
diff --git a/lib/image_sizer.rb b/lib/image_sizer.rb
index ee368ce3d1e..6e1646416cb 100644
--- a/lib/image_sizer.rb
+++ b/lib/image_sizer.rb
@@ -1,7 +1,7 @@
 module ImageSizer
 
   # Resize an image to the aspect ratio we want
-  def self.resize(width, height, opts = {})
+  def self.resize(width = nil, height = nil, opts = {})
     return if width.blank? || height.blank?
 
     max_width = (opts[:max_width] || SiteSetting.max_image_width).to_f
diff --git a/spec/components/image_sizer_spec.rb b/spec/components/image_sizer_spec.rb
index b0132671016..f3c0960d79e 100644
--- a/spec/components/image_sizer_spec.rb
+++ b/spec/components/image_sizer_spec.rb
@@ -24,6 +24,10 @@ describe ImageSizer do
     expect(ImageSizer.resize('100', '101')).to eq([100, 101])
   end
 
+  it 'returns nil if no width or height are provided' do
+    expect(ImageSizer.resize).to eq(nil)
+  end
+
   describe 'when larger than the maximum width' do
 
     before do