Systems, methods, and computer-readable storage media for resizing images using seam carving techniques are disclosed. The methods may facilitate efficient re-computation of the energy of an image between seam carving iterations in a resizing operation by re-computing only the energy of pixels and/or seams in the neighborhood of removed and/or replicated seams. The neighborhood and pixels for which energy values are updated may be dependent on the energy function employed by the seam carving techniques. The efficient re-computation of image energy may facilitate the use of seam carving techniques in user-interactive environments. The methods may also be used to pre-compute a retargeting matrix, usable in performing retargeting operations on an input image without re-computing the energy and/or the lowest cost seam(s) of the image between iterations. The methods may be implemented as stand-alone applications or as program instructions implementing components of a graphics application, executable by a CPU and/or GPU.