jappoz's profile - activity

Hello everyone
I was trying to apply a pcl::RadiusOutlierRemoval to a 2D point cloud obtained by a laser scan when I realize that it won't work unless you use 3D points.... (at least so I figured out when my program had linking problems when using PointXY cloud and no problems by using PointXYZ clouds). I think to use PointXYZ with z = 0 will not be a good workaround for computational reasons.
Which kind of methods are available for clouds of PointXY to remove noisy points and outliers?
Thank you
Regards

Hello everyone!
I start saying that I am a neophyte in using PCL but I have a problem I cannot figure out how to solve.
I am writing a pedestrian detector and tracker which uses combined informations from Lidar and Camera. The point clouds I am handling are 2D laser scans.
The detections are made in the Image plane and then I can retrieve the position of each detection in the point cloud without any clustering.
My problem is that in this way I cannot have a good motion estimation to feed the Kalman Filter (which is tracking points onto the ground plane) so I am looking to some good technique to estimate the motion of a point given the current position and some old point clouds saved in a buffer.
Basically, the problem is to associate one single point (i.e. the detection) with another point belonging to the previous point cloud to be able to compute its estimated speed and orientation.
How could it be done by using PCL or other libraries?
I have seen online that the Nearest Neighbour could be the simplest way but is it possible to use the PCL NN (working with Kd-tree I guess) to find the points in a neighbourhood of ONE single point? Moreover, I am working with only 2 coordinates (2D laser scan), could it be an issue?
Sorry for that but I am a bit confused about the topic. Thank you
Best regards

Thank you. So I did and it worked fine.

Hello everybody I have a problem. I am using INDIGO. I am using as ROS MASTER my own account on my pc in communication with ROS running in a virtual machine. The problem is that I would like to subscribe a message which is defined in the nodes belonging to the virtual machine and not to my catkin folder. So basically when I compile trying to include such message, I get a compilation error saying that this package is not found. (Obviously, because it is defined in the virtual machine). Is there any workaround for that? Thank you

Thank you, this fixed the problem!

Can this due to the fact that the timestamp of the points message is very different from the one of the two images? If yes, how could I fix this?

Hello everybody. I am trying writing a code that projects rectangles (let's say ROI) in an image which is synchronized in this way:

sync = new message_filters::Synchronizer<MySyncPolicy> (MySyncPolicy(10), img_rec_sub, img_be_sub);
sync->registerCallback(boost::bind(&icarsStixelGenerator::dataCallback, this, _1, _2));

The rectangles that I would like to project are from a LaserScan (actually the message is customized but however they are basically points with and Header). In order to show the rectangles in the synchronized image I tried to modify the code like that

  sync = new message_filters::Synchronizer<MySyncPolicy> (MySyncPolicy(10), img_rec_sub, img_be_sub, stx_points_sub);
 sync->registerCallback(boost::bind(&icarsStixelGenerator::dataCallback, this, _1, _2));
 sync->registerCallback(boost::bind(&icarsStixelGenerator::stxCallback, this, _3));

Where stxCallback is the callback that acquires the points to be reprojected. Such points are drown inside the dataCallback callback which publishes the images. Well by doing this however no image is published in rviz. If I do not try to synchronize the points, and if I use a simple subscriber for the points, the images with the rectangles are visible but I am sure they are not synchronized. For sure I miss something stupid but cannot realize what. If you have any suggestion for me I will appreciate. Regards

here the stxcallback

void icarsStixelGenerator::stxCallback(const icars_laser_roi::stx_points::ConstPtr& points){


    points_x = points->points_x;
    points_y = points->points_y;
    points_ranges = points->points_ranges;

}

Moreover , my console shows the following warning :

[ WARN] [1457354314.860322713]: MessageFilter [target=map ]: Dropped 100,00% of messages so far. Please turn the [ros.rviz.message_notifier] rosconsole logger to DEBUG for more information.

Hello everybody. I am trying writing a code that projects rectangles (let's say ROI) in an image which is synchronized in this way:

sync = new message_filters::Synchronizer<MySyncPolicy> (MySyncPolicy(10), img_rec_sub, img_be_sub);
sync->registerCallback(boost::bind(&icarsStixelGenerator::dataCallback, this, _1, _2));

The rectangles that I would like to project are from a LaserScan (actually the message is customized but however they are basically points with and Header). In order to show the rectangles in the synchronized image I tried to modify the code like that

  sync = new message_filters::Synchronizer<MySyncPolicy> (MySyncPolicy(10), img_rec_sub, img_be_sub, stx_points_sub);
 sync->registerCallback(boost::bind(&icarsStixelGenerator::dataCallback, this, _1, _2));
 sync->registerCallback(boost::bind(&icarsStixelGenerator::stxCallback, this, _3));

Where stxCallback is the callback that acquires the points to be reprojected. Such points are drown inside the dataCallback callback which publishes the images. Well by doing this however no image is published in rviz. If I do not try to synchronize the points, and if I use a simple subscriber the images with the rectangles are visible but I am sure they are not synchronized. For sure I miss something stupid but cannot realize what. If you have any suggestion for me I will appreciate. Regards