Paperclip:为什么尽管质量下降了，但是图像的大小变化不大?

I am running Ruby on Rails 3 and I would like to reduce the size (in byte) of an uploading image using the Paperclip plugin/gem. I need that because I would like to improve the performance related to the loading time of web pages in my application.I am running Ruby on Rails 3 and I would like t