stack level too deep when uploading and resizing image using carrierwave and rmagick

When i am commenting this line "process :resize_to_fit => [200, 300]" in ImageUploader class then code is working fine but i want to resize the image when uploading. please help. Log: ``` Started PATCH "/products/980190968" for 127.0.0.1 at 2014-06-03 11:35:08 +0530 Processing by ProductsController#update as HTML Parameters: {"utf8"=>"✓", "authenticity_token"=>"D//KM/EExMDwT7WTMSQpsWnEDgAmpzGz7I7HembUC3s=", "product"=>{"title"=>"With No Image", "description"=>"asdasdasdasdasdasdasdsadasdasdasda", "image_url"=>#<ActionDispatch::Http::UploadedFile:0x2e936b0 @tempfile=#<Tempfile:C:/Users/ahmad/AppData/Local/Temp/RackMultipart20140603-1836-1098spu>, @original_filename="cs.jpg", @content_type="image/jpeg", @headers="Content-Disposition: form-data; name=\"product[image_url]\"; filename=\"cs.jpg\"\r\nContent-Type: image/jpeg\r\n">, "price"=>"39.90"}, "commit"=>"Update Product", "id"=>"980190968"} User Load (0.0ms) SELECT "users".* FROM "users" WHERE "users"."id" = 4 LIMIT 1 Product Load (1.0ms) SELECT "products".* FROM "products" WHERE "products"."id" = $1 LIMIT 1 [["id", 980190968]] Cart Load (1.0ms) SELECT "carts".* FROM "carts" WHERE "carts"."id" = $1 LIMIT 1 [["id", 76]] (0.0ms) BEGIN (1.0ms) ROLLBACK Completed 500 Internal Server Error in 108ms SystemStackError (stack level too deep): actionpack (4.1.1) lib/action_dispatch/middleware/reloader.rb:79 Rendered C:/Ruby200/lib/ruby/gems/2.0.0/gems/actionpack-4.1.1/lib/action_dispatch/middleware/templates/rescues/_source.erb (2.0ms) Rendered C:/Ruby200/lib/ruby/gems/2.0.0/gems/actionpack-4.1.1/lib/action_dispatch/middleware/templates/rescues/_trace.html.erb (2.0ms) Rendered C:/Ruby200/lib/ruby/gems/2.0.0/gems/actionpack-4.1.1/lib/action_dispatch/middleware/templates/rescues/_request_and_response.html.erb (2.0ms) Rendered C:/Ruby200/lib/ruby/gems/2.0.0/gems/actionpack-4.1.1/lib/action_dispatch/middleware/templates/rescues/diagnostics.erb within rescues/layout (118.0ms) ``` Here is my ImageUploader class: ``` class ImageUploader < CarrierWave::Uploader::Base # Include RMagick or MiniMagick support: include CarrierWave::RMagick # include CarrierWave::MiniMagick # Choose what kind of storage to use for this uploader: storage :file # storage :fog # This is a sensible default for uploaders that are meant to be mounted: def store_dir "uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}" end def default_url "/images/defaults/notAvailable.jpg" end # Process files as they are uploaded: #process :resize_to_fit => [200, 300] # For images you might use something like this: def extension_white_list %w(jpg jpeg gif png) end end ``` And this is the Product Model: ``` class Product < ActiveRecord::Base has_many :line_items has_many :orders, through: :line_items #has_and_belongs_to_many :categories before_destroy :ensure_not_referenced_by_any_line_item validates :title, :description, presence: true validates :price, numericality: {greater_than_or_equal_to: 0.01} validates :title, uniqueness: true validates :image_url, allow_blank: true, format: { with: %r{\.(gif|jpg|png)\Z}i, message: 'must be a URL for GIF, JPG or PNG image.' } validates :title, length: {minimum: 10} mount_uploader :image_url, ImageUploader def self.latest Product.order(:updated_at).last end private # ensure that there are no line items referencing this product def ensure_not_referenced_by_any_line_item if line_items.empty? return true else errors.add(:base, 'Line Items present') return false end end end ```