Equirectangular tile to rectilinear_v0.1 - FoxelSA/libgnomonic GitHub Wiki

The equirectangular tile to rectilinear gnomonic projection algorithm inherit of the specificities of the Eyesis4Pi panoramic camera. This projection is designed to be used when only a tile of the entire equirectangular mapping is available to perform gnomonic projection.

Considering the Eyesis4Pi data processing, the raw images coming from the sensors are heavily treated in term of chromatic aberrations and lense distortions. As a result, equirectangular tiles are provided by the process. This algorithm is set to retrieve the original sensor image from the tile, keeping all the performed correction.

To illustrate the process, we consider the following equirectangular mapping of a panorama taken using an Eyesis4Pi camera (copyright (c) Didier Mouron under CC BY-SA license) :

The considered equirectangular tile is extracted from the entire panorama and is given by :

Using the equirectangular tile to rectilinear gnomonic projection algorithm, the following rectilinear image is obtained :

The gnomonic projection is performed assuming hypothesis that come from the specificities of the Eyesis4Pi camera data processing and should not be considered as a general projection algorithm.