 
Summary: To appear in the ACM SIGGRAPH conference proceedings
Efficient GradientDomain Compositing Using Quadtrees
Aseem Agarwala
Adobe Systems, Inc.
Abstract
We describe a hierarchical approach to improving the efficiency of
gradientdomain compositing, a technique that constructs seamless
composites by combining the gradients of images into a vector field
that is then integrated to form a composite. While gradientdomain
compositing is powerful and widely used, it suffers from poor scal
ability. Computing an n pixel composite requires solving a linear
system with n variables; solving such a large system quickly over
whelms the main memory of a standard computer when performed
for multimegapixel composites, which are common in practice. In
this paper we show how to perform gradientdomain compositing
approximately by solving an O(p) linear system, where p is the to
tal length of the seams between image regions in the composite; for
typical cases, p is O(
n). We achieve this reduction by transform
