Re: [otb-users] Stereo Rectification Grid Generator

[Guillaume Pasero]

Hi, This "epi.step" is the step at which the deformation grid (to resample into epipolar) is computed. The computation of these grids are not streamed nor multi-threaded, the whole grid will be allocated in memory (sadly there are still some filters like this in OTB). I don't think the mpirun will help in this particular case. For large images, it is advised to use a step larger than 1. If you use a smooth or low-resolution DEM, the transform between sensor and epipolar space will be quite regular, so you can afford computing this transform 1 pixel every 5. Regards, Guillaume On 02/01/2017 03:32 PM, M. Jahanzeb Malik wrote: Hi, I have just started using OTB 5.8.0 on ubuntu 16.04 LTS. I am exercising examples in the cook book. But, now I am stuck with otbcli_StereoRectificationGridGenerator. I am running the grid generator with -epi.step 1 (which is default value) on a world view 2 pan image as:  otbcli_StereoRectificationGridGenerator -io.inleft image1.tif -io.inright image2.tif -epi.step 1 -io.outimage1 outimage1_grid.tif -io.outright outimage1_grid.tif But, the command hanged/stuck while writing outimage1_grid.tif. The command worked very slow and did not utilize all cores on my PC. I will be grateful if some let me know following: How does the grid generator make the transformation grid (algorithm ?), why it is so computationally expensive? Can I run the grid generator using mpirun -np 4 otbcli_StereoRectificationGridGenerator -io.inleft image1.tif -io.inright image2.tif -epi.step 1 -io.outimage1 outimage1_grid.tif -io.outright outimage1_grid.tif? I also noted that the grid generator worked nicely with -epi.step 5. But the issue is I want to process the data at the full resolution (i.e., all pixels in the raw image). How can I do that? -- Kind Regards M. Jahanzeb Malik -- -- Check the OTB FAQ at http://www.orfeo-toolbox.org/FAQ.html   You received this message because you are subscribed to the Google Groups "otb-users" group. To post to this group, send email to otb-users@googlegroups.com To unsubscribe from this group, send email to otb-users+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/otb-users?hl=en --- You received this message because you are subscribed to the Google Groups "otb-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to otb-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout. -- Guillaume PASERO Responsable technique Business Unit ESPACE & GeoInformation - Département Payload Data & Applications CS Systèmes d'Information Parc de la Grande Plaine - 5, Rue Brindejonc des Moulinais - BP 15872 31506 Toulouse Cedex 05 - FRANCE +33 561 17 64 21 - guillaume.pas...@c-s.fr -- -- Check the OTB FAQ at http://www.orfeo-toolbox.org/FAQ.html   You received this message because you are subscribed to the Google Groups "otb-users" group. To post to this group, send email to otb-users@googlegroups.com To unsubscribe from this group, send email to otb-users+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/otb-users?hl=en --- You received this message because you are subscribed to the Google Groups "otb-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to otb-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.