paperclip imagemagic api &paperclip relevent

http://www.imagemagick.org/Magick++/Geometry.html

http://jimneath.org/2008/04/17/paperclip-attaching-files-in-rails/

http://yangzhihuan.javaeye.com/blog/704331

step by step 

good

=>http://patshaughnessy.net/2009/4/30/paperclip-sample-app

http://thewebfellas.com/blog/2008/11/2/goodbye-attachment_fu-hello-paperclip

http://burm.net/2008/10/07/the-ruby-on-rails-paperclip-plugin-tutorial-easy-image-attachments/

paperclip 读默认图片

http://why404.appspot.com/setting-a-default-image-with-Paperclip

papperclip 聚合链http://fireflyman.javaeye.com/blog/704792

华顺http://huacnlee.com/blog/rails-plugin-paperclip-for-image-upload