Fix bug.

app/models/ad_image.rb

@@ -4,7 +4,7 @@ class AdImage
   include Mongoid::Document
   include Mongoid::Timestamps
 
-  mount_uploader :file, ImageUploader
+  mount_uploader :file, BannerImageUploader
   mount_uploader :video_file, BannerUploader
   mount_uploader :video_file_webm, BannerUploader
 

app/uploaders/banner_image_uploader.rb

@@ -0,0 +1,90 @@
+# encoding: utf-8
+require 'carrierwave/processing/mime_types'
+
+class BannerImageUploader < CarrierWave::Uploader::Base
+
+  # Include RMagick or MiniMagick support:
+  # include CarrierWave::RMagick
+  # include CarrierWave::MiniMagick
+  include CarrierWave::MiniMagick
+  include CarrierWave::MimeTypes
+
+  # Choose what kind of storage to use for this uploader:
+  storage :file
+  # storage :fog
+
+  # Override the directory where uploaded files will be stored.
+  # This is a sensible default for uploaders that are meant to be mounted:
+  def store_dir
+    "uploads/banner_image/#{mounted_as}/#{model.id}"
+  end
+
+   # override
+  def filename
+    @original_filename
+  end
+
+  # override
+  def original_filename=(filename)
+    @original_filename = super(filename)
+
+    if(@original_filename.bytesize > 200)
+      original_file_extension = File.extname(@original_filename)
+
+      @original_filename.force_encoding("ascii-8bit")
+      @original_filename = @original_filename[0, (200 - original_file_extension.bytesize)]
+      @original_filename.encode!("UTF-16BE", "UTF-8", :invalid => :replace, :undef => :replace, :replace => '')
+      @original_filename.encode!("UTF-8")
+
+      @original_filename += original_file_extension
+    end
+
+    @original_filename
+  end
+
+  def fix_exif_rotation 
+    manipulate! do |img|
+      img.tap(&:auto_orient)
+    end
+  end
+  # Provide a default URL as a default if there hasn't been a file uploaded:
+  # def default_url
+  #   # For Rails 3.1+ asset pipeline compatibility:
+  #   # ActionController::Base.helpers.asset_path("fallback/" + [version_name, "default.png"].compact.join('_'))
+  #
+  #   "/images/fallback/" + [version_name, "default.png"].compact.join('_')
+  # end
+
+  # Process files as they are uploaded:
+  # process :scale => [200, 300]
+  #
+  # def scale(width, height)
+  #   # do something
+  # end
+
+  # Create different versions of your uploaded files:
+   version :thumb do
+     process :fix_exif_rotation
+     process :resize_to_fit => [400, 400]
+   end
+
+   version :mobile do
+    process :fix_exif_rotation
+    process :resize_to_limit => [1152, 768]
+  end
+
+  # Add a white list of extensions which are allowed to be uploaded.
+  # For images you might use something like this:
+  def extension_white_list
+     %w(jpg jpeg gif png bmp)
+  end
+
+  # Override the filename of the uploaded files:
+  # Avoid using model.id or version_name here, see uploader/store.rb for details.
+  # def filename
+  #   "something.jpg" if original_filename
+  # end
+
+
+
+end