Building Computer Vision Projects with OpenCV 4 and C++

3D reconstruction and visualization

Having obtained the tracks in principle, we need to align them in a data structure that OpenCV's SfM module expects. Unfortunately, the sfm module is not very well documented, so this part we have to figure out on our own from the source code. We will be invoking the following function under the cv::sfm:: namespace, which can be found in opencv_contrib/modules/sfm/include/opencv2/sfm/reconstruct.hpp:

void reconstruct(InputArrayOfArrays points2d, OutputArray Ps, OutputArray points3d, InputOutputArray K, bool is_projective = false);

The opencv_contrib/modules/sfm/src/simple_pipeline.cpp file has a major hint as to what that function expects as input:

static voidparser_2D_tracks( const std::vector<Mat> &points2d, ...