I would love to understand your scenario. Please, please, please let me
know what you're trying to accomplish - post a reply here:
http://blogs.msdn.com/infopath/archive/2006/09/25/771304.aspx
About your question - it's possible to do in InfoPath, but it's pretty
hard to do. You need to extract form files (unpack the XSN), find the
XSLT of the current view. Then, you need to modify the XSLT to have
width and height parameters of the image point to some XPath instead of
a static value (use xsl value-of).
Thanks,
Alex Weinstein [MSFT]