3.6.2 Resample images in epipolar geometry

The former application generates two grids of displacements. The GridBasedImageResampling allows to resample the two input images in the epipolar geometry using these grids. These grids are intermediary results not really useful on their own in most cases. This second step only consists in applying the transformation and resample both images. This application can obviously be used in lot of other contexts.

The two commands to generate epipolar images are:

otbcli_GridBasedImageResampling -io.in image1.tif  
                                -io.out image1_epipolar.tif  
                                -grid.in outimage1_grid.tif  
                                -out.sizex 4462  
                                -out.sizey 2951

otbcli_GridBasedImageResampling -io.in image2.tif  
                                -io.out image2_epipolar.tif  
                                -grid.in outimage2_grid.tif  
                                -out.sizex 4462  
                                -out.sizey 2951

As you can see, we set sizex and sizey parameters using output values given by the StereoRectificationGridGenerator application to set the size of the output epipolar images.


PIC PIC

Figure 3.22: Extract of resample image1 and image2 in epipolar geometry over Pyramids of Cheops. ©CNES 2012


We obtain two images in epipolar geometry, as shown in figure 3.22. Note that the application allows to resample only a part of the image using the -out.ulx and -out.uly parameters.