Pcl icp implementation in pytorch cpp extension

1

Environments:
ubuntu 16.04 + anaconda 2 + pytorch 0.4.0

I’m trying to build a cpp extension for point cloud iterative closest point using the icp function in pcl-1.7 http://pointclouds.org/documentation/tutorials/iterative_closest_point.php.

The data transforming from at::tensor to pcl::Pointcloud is fine. However, as soon as I declare a new icp object, there will be a segmentation fault.

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image1694×739 335 KB

This line triggers the fault:

pcl::IterativeClosestPoint<pcl::PointXYZ, pcl::PointXYZ> icp;

The setup.py file is:

setup(
    name='icp_cpp',
    version='1.0',
    ext_modules=[
        CppExtension(
            name='icp_cpp',
            sources = ['icp_op.cpp'],
            library_dirs=['/usr/lib/x86_64-linux-gnu'],
            libraries=[*pcl related libraries*],
            include_dirs=["/usr/include/pcl-1.7/",
                          "/usr/include/eigen3"])],
    cmdclass={
    'build_ext': BuildExtension
})

I also tried to add more arguments to the CppExtension as python-pcl/setup.py at master · strawlab/python-pcl · GitHub. But it doesn’t help.

To repeat the bug, you can clone the related files from https://github.com/onlytailei/icp_extension.
There should be pcl and eigen in the system

sudo apt-get install libpcl-all
sudo apt-get install libeigen3-dev

Then build the extension through:

python setup install.py

Comment/Uncomment line 72 in icp_op.cpp

pcl::IterativeClosestPoint<pcl::PointXYZ, pcl::PointXYZ> icp;

And rebuild the extension, you will see the difference.

python icp_test.py
2

Random guess: maybe PCL is stealing the ownership of a Torch Tensor, and that is causing the segfault?

3

Thanks!

The problem is that I only declare a new icp object like

pcl::IterativeClosestPoint<pcl::PointXYZ, pcl::PointXYZ> icp;

As soon as you uncomment this one, the segfault happen. I’m not starting to input any point cloud to it.
In the pure cpp example, everything is fine.

4

Do you have the segfault if you comment out everything in https://github.com/onlytailei/icp_extension/blob/master/icp_op.cpp#L29-L65 ?

5

I tried. It doesn’t help.
The segfault is still coming from line 72.

6

Let’s move the discussion to https://github.com/pytorch/extension-cpp/issues/20