Strip exif data from uploaded images

Using `-strip` cli options from ImageMagick

http://www.imagemagick.org/script/command-line-options.php#strip

fix #85

app/models/media_attachment.rb

@@ -5,7 +5,10 @@ class MediaAttachment < ApplicationRecord
   belongs_to :account, inverse_of: :media_attachments
   belongs_to :status,  inverse_of: :media_attachments
 
-  has_attached_file :file, styles: -> (f) { f.instance.image? ? { small: '510x680>' } : { small: { convert_options: { output: { vf: 'scale="min(510\, iw):min(680\, ih)":force_original_aspect_ratio=decrease' } }, format: 'png', time: 1 } } }, processors: -> (f) { f.video? ? [:transcoder] : [:thumbnail] }
+  has_attached_file :file,
+    styles: -> (f) { file_styles f },
+    processors: -> (f) { f.video? ? [:transcoder] : [:thumbnail] },
+    convert_options: { all: "-strip" }
   validates_attachment_content_type :file, content_type: IMAGE_MIME_TYPES + VIDEO_MIME_TYPES
   validates_attachment_size :file, less_than: 4.megabytes
 
@@ -30,4 +33,26 @@ class MediaAttachment < ApplicationRecord
   def type
     image? ? 'image' : 'video'
   end
+
+private
+  def self.file_styles(f)
+    if f.instance.image?
+      {
+        original: '100%',
+        small: '510x680>'
+      }
+    else
+      {
+        small: {
+        convert_options: {
+          output: {
+            vf: 'scale="min(510\, iw):min(680\, ih)":force_original_aspect_ratio=decrease'
+          }
+        },
+        format: 'png',
+        time: 1
+        }
+      }
+    end
+  end
 end