PCL IterativeClosestPoint unable to find nearest neighbour
I'm using the RGBDSLAM from http://www.ros.org/wiki/rgbdslam to create a map with my Kinect. The general ICP implementation provided is a bit buggy so I wanted to replace that with the ICP from PCL. Used the tutorial and everything compiles fine. But when executed the ICP does not converge but outputs this error message:
[pcl::IterativeClosestPoint::computeTransformation] Unable to find a nearest neighbour in the target dataset for point 3 in the source!
I'd like to narrow down the cause for this, so if anyone has any experience with the parameters of the PCL ICP, I'd really appreciate if you share them! Just so I have an idea what parameters should work for this scenario. If I can rule out wrong parameters (especially max iterations and distance) I can dig into the pointclouds themselves to see if I am somehow messing up target and input cloud or have the wrong transformations or whatever.
I'm using ROS diamondback on Ubuntu 10.10 32bit with the provided PCL.
UPDATE: I tried several sets of parameters, though nothing seems to impact this. I have saved out two input pointclouds that I try to align with the icp, you can download them here if you like. I'm pretty much out of ideas on this. Unfortunately the documentation is rather lacking...
To further clarify what I'm doing:
pcl::IterativeClosestPoint<pcl::PointXYZRGB,pcl::PointXYZRGB> icp;
icp.setInputCloud(inputcloud.makeShared());
icp.setInputTarget(targetcloud.makeShared());
pcl::PointCloud<pcl::PointXYZRGB> final;
icp.align(final);
The above download contains inputcloud and targetcloud as they are saved right before icp.align().
UPDATE2: Using the ICP test sample program and the provided sample files bun0.pcd and bun4.pcd I found out that the problem seems to be specific to my pointclouds as those samples work fine. Are there any preconditions that the pointclouds must fulfill for ICP to work?
