Panorama Tools is the most versatile package for panoramic image manipulation. It uses high quality image transformations.
It can handle every imaginable lens type, can output to many formats and projections, including 360-degree spherical and rectilinear ('flat') formats. It can even correct lens distortion, use multiple rows of images and stitch tilted images. Although its features are numerous, Panorama Tools can be difficult to use and that's why PTGui was written. PTGui is a (Windows and Mac) front end for the great Panorama Tools package, for creating panoramic pictures. PTGui provides an easy to use point-and-click interface and hides all Panorama Tools' scripting commands from the user.
If you want to stitch panoramic images, Panorama Tools is the best photo stitching software there is.
Features of PTGui: