Imadaem is a daemon for responsive images built with JS and PHP. The code by Anatol Broder is available under the MIT License at Github. Imadaem depends on Jquery and Timthumb.
Very nice combining low quality image placeholders with responsive images for the second higher resolution image. This achieves both goals — the preloader kicks off the low res image request early so the user sees something quickly, and then JS kicks off the high res image request with the appropriate size to make it faster and reduce data costs.
— Steve Souders, Head Performance Engineer at Google
