Graphics Processing based image geometry correction is very effective for content that originates in the PC.
The drawback of Signal Processing based Image Geometry Correction is the extra expense of the hardware that is used to perform it.
This extra expense can be mitigated by the inclusion of additional features (such as switching and Edge Blending in the Signal Processing based image geometry correction system).
The number of points in the 2-dimensional array that are required to do an accurate Image Geometry Correction depends on the surface involved.
Keystone correction capabilities are now included in most projectors currently available on the market, allowing users to move the image both vertically and horizontally.
Image Geometry Correction onto regular surfaces (such as spheres and cylinders) is the next level of complexity.
Both these regular shapes are encountered frequently in Professional Audio Video (Pro AV) situations, in the form of domed or curved wall theatres.
Edge blending enables the seamless projection of a large image using several overlapping projectors.
Since Keystone Distortion (and frequently the requirement of projection onto a non-flat surface) is a built-in requirement of almost all Edge Blending systems, the pairing of Edge blending and image geometry correction in the same video signal processor is a natural one.