title: how to remove background image and get fore image
body: <p>there are two images</p>
  
  <p><a href="http://bbs.shoucangshidai.com/attachments/month_1001/1001211535bd7a644e95187acd.jpg">alt text http://bbs.shoucangshidai.com/attachments/month_1001/1001211535bd7a644e95187acd.jpg</a>
  <a href="http://bbs.shoucangshidai.com/attachments/month_1001/10012115357cfe13c148d3d8da.jpg">alt text http://bbs.shoucangshidai.com/attachments/month_1001/10012115357cfe13c148d3d8da.jpg</a>
   one is background image another one is a person's photo with the same background ,same size,what i want to do is remove the second image's background and distill the person's profile  only. the common method is subtract first image from the second one,but my problem is if the color of person's wear is similar to the background. the result of subtract is awful. i can not get whole people's profile. who have good idea to remove the background give me some advice.
  thank you in advance.</p>