像素图片实现跟踪

像素图片实现跟踪指在html中加入1像素的img标签。
在访问该html页面时，可以统计出源来的ip,referrer,useragent等信息。
可以用来统计pu,pv。

The tracking pixel allows to track how many times a webpage have been viewed (visits) or how many time an email was opened (opens).
Tracking pixel is a little piece of code containing an
image (1 pixel * 1pixel dimension) that should be inserted in the pages
of your website or in the email you send.

Tracking pixels could be used also track conversion. You will able to
know which user, from which page of you site, or from which email or
blog lead to a conversion, also if he just visited the page and did not
clicked on your tracking link.

检测邮件打开率

在邮件内容中插入一个1px的跟踪图片文件。当邮件被打开时，就会自动加载这个1px的图片。只要知道这个图片的加载次数，就可以相应的得到邮件被打开的次数。

在之前解析邮件时，就能发现在邮件中有个1像素的图片。

参考

• How does a tracking pixel work?
• 利用像素图片收集攻击目标信息
• 如何用 1px 的图片做数据统计