基于canvas的前端图片压缩
https://github.com/think2011/localResizeIMG3
https://github.com/gokercebeci/canvasResize
http://www.jincon.com/archives/336
https://github.com/think2011/localResizeIMG3
https://github.com/gokercebeci/canvasResize
http://www.jincon.com/archives/336