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[hcscysh]

When I use the reconstruction.py to sparse reconstruction.I get the error, Linear solver failure. Failed to compute a step: Eigen failure. Unable to perform dense Cholesky factorization.But when I can export the ply of reconstruction successfuly. the hint is a warning or is a errot, it Influence the result of the reconstruction?

[xuelunshen]

I sometimes encounter this output (Eigen failure) during reconstruction, which likely occurs when solving for the pose or other numerical values of certain images fails. If you pay attention, you should see the reconstruction results at the end of sparse reconstruction, such as the number of successfully reconstructed images / images involved in the reconstruction. If some images fail to participate in the reconstruction, it should result in the number of successfully reconstructed images being fewer than the number of images involved in the reconstruction. Anyway, as long as you can obtain the reconstructed ply file, it indicates that the sparse reconstruction has produced some results for you.

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我有时候进行重建时, 也会看见这个输出 (Eigen failure), 它应该是在解算某些图像的 pose 等数值时, 解算失败了而出现的. 如果你注意观察, 应该会在 sparse reconstruction 的结尾看到重建的结果, 比如 成功重建的图像/参与重建的图像 等. 如果某些图像参与重建失败, 应该会使得成功重建的图像数量少于参与重建的图像数量. 不管怎么样, 你只要能拿到重建后的 ply 文件, 说明 sparse reconstruction 还是给你重建了一些东西出来.

[hcscysh]

Thanks for your reply. I find when I reconstruction the big scene that inlcude many images, the speed is very slow. When I debug the code ,it's very hard. if I can save the reconstruction, and load again in the debug mode.
reconstruction = reconstruction.main(),I use the reconstruction.write ,but it faild.How can I can I save the reconstruction?

[hcscysh]

The ply of reconstruction exported, the distance of scene is much smaller than the actual. For example the fact distance is 100 meters, the ply's distance is only 10 meters

[xuelunshen]

Thanks for your reply. I find when I reconstruction the big scene that inlcude many images, the speed is very slow. When I debug the code ,it's very hard. if I can save the reconstruction, and load again in the debug mode. reconstruction = reconstruction.main(),I use the reconstruction.write ,but it faild.How can I can I save the reconstruction?

For the saving and loading of reconstruction models, you can refer to the code in hloc. This part is difficult for me to explain here, so I suggest you directly look at the code and use cases in hloc.

[xuelunshen]

The ply of reconstruction exported, the distance of scene is much smaller than the actual. For example the fact distance is 100 meters, the ply's distance is only 10 meters

The inaccuracy of the scale is normal because the current reconstruction code has no real-world scale input and constraints. It seems that you want to reconstruct and measure the real world. If the reconstructed structure is correct, you can try scaling it proportionally to see (this is the simplest but not guaranteed to work method).