Stereo Framework

Brief Description

Compute the ground elevation based on one or multiple stereo pair(s)



Long Description

Compute the ground elevation with a stereo block matching algorithm between one or multiple stereo pair in sensor geometry. The output is projected in desired geographic or cartographic map projection (WGS84 by default).

This application is chaining different processing steps. Some of them are also performed by other applications in the stereo-reconstruction framework:
* StereoRectificationGridGenerator [1] : for the generation of deformation grids
* GridBasedImageResampling [2] : resampling into epipolar geometry
* BlockMatching [3] : estimation of dense disparity maps

The pipeline executes the following steps on each stereo pair:
- compute the epipolar displacement grids from the stereo pair (direct and inverse)
- resample the stereo pair into epipolar geometry using BCO interpolation
- create masks for each epipolar image : remove black borders and resample input masks
- compute horizontal disparities with a block matching algorithm
- refine disparities to sub-pixel precision with a dichotomy algorithm
- apply an optional median filter
- filter disparities based on the correlation score and exploration bounds
- translate disparities in sensor geometry
- convert disparity to 3D Map.

Then all 3D maps are fused to produce DSM. The fusion method in each DEM cell can be chosen between maximum, minimum and average.





See also

[1] StereoRectificationGridGenerator
[2] GridBasedImageResampling
[3] BlockMatching

Example of use