I dont know how to do it but i think that it must be possible somehow.. ie when u right click on a pic and get the properties (in Internet Explorer) it gives u the pic dimensions whether or not they were set in html. Now, maybe there is some processing of the pic in the background or maybe it somehow reads the file header information. I would assume that each type of pic stores the dimensions somewhere at the start of the file. Maybe some graphicky person knows this...