In general, there are two major calibration tasks for the proposed multi-projection systems: the geometrical and photometrical system calibration.
 
As illustrated in the figure below, the photometric calibration can be splitted into three parts, the compensation of the photometric deviations between the projectors (white balance, black level), the compensation of projector lens vignetting effects and the adaptation of border blending parameters (gamma correction). 
  
The geometrical calibration again consists of three tasks. Firstly, according to the number of projectors the original image needs to be split into overlapping sub-images. Secondly, these sub-images need to be adapted to the existing screen geometry. Finally, the deviations caused by the projectors lens distortion or by curved screens need to be compensated.

Competencies

• Fully automatic calibration of multi-projector setups based on a digital camera system
• Photometric and geometric calibration for arbitrary screen surfaces
• Compensation of the non-linear projection characteristics of the projectors as well as the deviations of white-balance and black level between the projectors