Break out of overflow hidden with relative positioned fixed elements

"For elements whose layout is governed by the CSS box model, any value other than none for the transform results in the creation of both a stacking context and a containing block. The object acts as a containing block for fixed positioned descendants."
http://dev.w3.org/csswg/css-transforms/#transform-rendering

<div style="transform: translate3d(0,0,0);overflow:hidden">
   <img style="position:fixed; ..." />
</div>

To position the element relative to a parent element simply set a transform style to the parent.
The parent will now act as a containing block for fixed children.