In the Img tag, we know that the image has an OnLoad event that fires when the images finish loading. But can we get the accurate measure when the image begin to download? I am trying to measure a website's Page Load Time, so knowing how long it takes for an image to load will be part of my analysis if that's possible.

I would like to do it from an automated fashion, so I can measure real client experiences instead of putting my website on Yslow or PingDom( <http://tools.pingdom.com/fpt/>). I have tried to look into Navigation Timing Apis (http://w3c-test.org/webperf/specs/NavigationTiming/) unfortunately even they provide insights such as DNS resolution time, but resource fetching within the web request doesn't seemed to be supported.