PHP采集程序问题
<br> <td id="prodImageCell" height="280" width="280"><a href="http://www.amazon.co.jp/gp/product/images/B007HDJPOU/ref=dp_image_0/375-3424220-7267256?ie=UTF8&n=3828871&s=kitchen" target="AmazonHelp" onclick="return amz_js_PopWin(this.href,'AmazonHelp','width=700,height=600,resizable=1,scrollbars=1,toolbar=1,status=1');" >@@##@@</a><br><br><br><br> <td id="prodImageCell" height="280" width="280"><a href="http://www.amazon.co.jp/gp/product/images/B005318B0C/ref=dp_image_0/376-2257022-2490017?ie=UTF8&n=13299531&s=toys" target="AmazonHelp" onclick="return amz_js_PopWin(this.href,'AmazonHelp','width=700,height=600,resizable=1,scrollbars=1,toolbar=1,status=1');" >@@##@@</a><br>
这两段是我采集过来的，采集两个产品页面，我就想要产品图片的地址
http://ec2.images-amazon.com/images/i/418qdk6bctl._sl500_aa280_.jpg
http://ec2.images-amazon.com/images/i/51bslaswkvl._sl500_aa280_.jpg
整个页面的代码很多，我就是想要这个图片
http://ec2.images-amazon.com/images/i/
._sl500_aa280_.jpg
以上两段每个页面都是一样的，请问怎么过滤我想要的这个图片地址
