using only some of the images from the Eyesis-4pi camera

[polto]

Hi Pierre,

Could you please implement a filter to specify only some images from Eyesis-4pi to be used in the reconstruction (for example the two stereo-pairs) ?

Also, since all intrinsic & extrinsic parameters of the rig are known how to disallow OpenMVG to adjust them later during the pipeline ?
Regards.

[pmoulon]

Hi @polto,

1. implement a channel filter must be easy, I will consider this task when pushing a commit for the feature. Stay tuned ;-)
2. In order to disable intrinsic parameter refinement you must use the option -f NONE on GlobalSfM 🎃

[polto]

thanks @pmoulon !

[pmoulon]

I let the task as open since I have not yet handle it

[pmoulon]

Feature ready to test.
Please checkout the branch develop_channel_filter then you can use the option -c
Use a list of ids you wanna keep. If you want to keep sensor 1,2,3,6 you can do
-c "1;2;3;6"

[polto]

I have an error trying to build this branch.

root@d01:~/OpenMVG_SfMImageListing_Elphel_Camera_Build# make -j8
Scanning dependencies of target libfastcal
[ 33%] [ 66%] Building C object third_party/libfastcal/CMakeFiles/libfastcal.dir/src/fastcal-query.c.o
Building C object third_party/libfastcal/CMakeFiles/libfastcal.dir/src/fastcal-parser.c.o
Linking C static library liblibfastcal.a
[ 66%] Built target libfastcal
Scanning dependencies of target main_openMVG_SfMImageListing_Elphel_Camera
[100%] Building CXX object CMakeFiles/main_openMVG_SfMImageListing_Elphel_Camera.dir/main.cpp.o
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp: In function ‘int main(int, char**)’:
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:85:41: error: parameter declared ‘auto’
         [&channel_to_keep](const auto & val)
                                         ^
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp: In lambda function:
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:87:15: error: ‘val’ was not declared in this scope
           if (val.empty()) // in order to handle input like ";" or ";;;"
               ^
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:90:32: error: ‘val’ was not declared in this scope
           std::stringstream os(val);
                                ^
In file included from /usr/include/c++/4.8/algorithm:62:0,
                 from /usr/local/include/openMVG/third_party/eigen/Eigen/Core:160,
                 from /usr/local/include/openMVG/numeric/numeric.h:35,
                 from /root/OpenMVG_SfMImageListing_Elphel_Camera/elphel_utils.hpp:28,
                 from /root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:20:
/usr/include/c++/4.8/bits/stl_algo.h: In instantiation of ‘_Funct std::for_each(_IIter, _IIter, _Funct) [with _IIter = __gnu_cxx::__normal_iterator<std::basic_string<char>*, std::vector<std::basic_string<char> > >; _Funct = main(int, char**)::__lambda14]’:
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:94:7:   required from here
/usr/include/c++/4.8/bits/stl_algo.h:4417:14: error: no match for call to ‘(main(int, char**)::__lambda14) (std::basic_string<char>&)’
  __f(*__first);
              ^
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:85:26: note: candidate is:
         [&channel_to_keep](const auto & val)
                          ^
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:85:44: note: main(int, char**)::__lambda14
         [&channel_to_keep](const auto & val)
                                            ^
/root/OpenMVG_SfMImageListing_Elphel_Camera/main.cpp:85:44: note:   candidate expects 0 arguments, 1 provided
lsmake[2]: *** [CMakeFiles/main_openMVG_SfMImageListing_Elphel_Camera.dir/main.cpp.o] Error 1
make[1]: *** [CMakeFiles/main_openMVG_SfMImageListing_Elphel_Camera.dir/all] Error 2
make: *** [all] Error 2

[pmoulon]

Does changing auto to std::string is working?

[polto]

oh yeah !
launching a long test. :)

[pmoulon]

Using auto as lambda parameter is authorized in C++14 or not C++11, that is explaining the error.
👍

[polto]

it's working. Here is a small segment processed with channels 10;14;24;25 (both stereo pairs looking in opposite directions)

this is the result of GlobalSfM. I am running now openMVG_main_ComputeStructureFromKnownPoses , but the last step "Per triplet tracks validation (discard spurious correspondences):" is really slow.

Could you please explain these parameters of openMVG_main_ComputeStructureFromKnownPoses :

[-f|--match_file] path to a matches file (loaded pair indexes will be used)
[-p|--pair_file] path to a pairs file (only those pairs will be considered to compute the structure)
[-b|--bundle_adjustment] (switch) perform a bundle adjustment on the scene (OFF by default)

I do not really understand why would you need to provide match_pairs file after you have done the SfM.

Now, once we are done with SfM using only several channels, how can I export all channels from the rigid rig to PMVS, OpenMVS or MVE ?