Transfering Pointcloud from camera coordinate to world coordinate!

classic Classic list List threaded Threaded
6 messages Options
Reply | Threaded
Open this post in threaded view
|

Transfering Pointcloud from camera coordinate to world coordinate!

Nims
This post was updated on .
CONTENTS DELETED
The author has deleted this message.
Reply | Threaded
Open this post in threaded view
|

Re: Transfering Pointcloud from camera coordinate to world coordinate!

aichim
Administrator
Hi,

I don't understand what you are trying to achieve. Can you please try explaining again?

Cheers,
Alex
---
http://www.openperception.org



On Feb 4, 2013, at 1:41 PM, Nims <[hidden email]> wrote:

> I am using
> pcl::transformPointCloud(*cloud,*cloud2,pcl::getTransformation(tx,ty,tz,ALFA,BETHA,GAMMA));
> to transform pointclouds into world's coordinate, but i am not sure If I am
> assigning the values for translation vector and rotation angles correctly.
> Actually in current stage I am only concerned about estimating height of the
> points with respect to the floor(world coordinate that its origin is on the
> floor). Can anyone help me with it?
>
> Cheers
>
>
>
> --
> View this message in context: http://www.pcl-users.org/Transfering-Pointcloud-from-camera-coordinate-to-world-coordinate-tp4025867.html
> Sent from the Point Cloud Library (PCL) Users mailing list mailing list archive at Nabble.com.
> _______________________________________________
> [hidden email] / http://pointclouds.org
> http://pointclouds.org/mailman/listinfo/pcl-users

_______________________________________________
[hidden email] / http://pointclouds.org
http://pointclouds.org/mailman/listinfo/pcl-users
Reply | Threaded
Open this post in threaded view
|

Re: Transfering Pointcloud from camera coordinate to world coordinate!

Nims
In reply to this post by Nims
Hi Alex,

Sure, I have a pointcloud of a room captured by kinect. Assume that there is a certain object in this pointcloud and I have index of its center. I want to estimate the height of this point with respect to the floor. I also know the location and tilt of the sensor.

I hope the question is more clear now.

Cheers,  
Reply | Threaded
Open this post in threaded view
|

Re: Transfering Pointcloud from camera coordinate to world coordinate!

aichim
Administrator
Hi,

If you know the location and tilt of the sensor in world coordinates, you can then simply build the 4x4 transformation matrix for this pose and then give it to transformPointCloud in order to get your cloud in world coordinates.

But in order to determine where your object is and where the floor is, you will need to add some semantics to your cloud: object recognition, large plane segmentation etc. It is not completely trivial.

Cheers,
Alex
---
http://www.openperception.org



On Feb 5, 2013, at 7:32 AM, Nims <[hidden email]> wrote:

> Hi Alex,
>
> Sure, I have a pointcloud of a room captured by kinect. Assume that there is
> a certain object in this pointcloud and I have index of its center. I want
> to estimate the height of this point with respect to the floor. I also know
> the location and tilt of the sensor.
>
> I hope the question is more clear now.
>
> Cheers,  
>
>
>
> --
> View this message in context: http://www.pcl-users.org/Transfering-Pointcloud-from-camera-coordinate-to-world-coordinate-tp4025867p4025898.html
> Sent from the Point Cloud Library (PCL) Users mailing list mailing list archive at Nabble.com.
> _______________________________________________
> [hidden email] / http://pointclouds.org
> http://pointclouds.org/mailman/listinfo/pcl-users

_______________________________________________
[hidden email] / http://pointclouds.org
http://pointclouds.org/mailman/listinfo/pcl-users
Reply | Threaded
Open this post in threaded view
|

Re: Transfering Pointcloud from camera coordinate to world coordinate!

Nims
When The coordinates are in the world coordinate , is n't the z value of a point its height?
Reply | Threaded
Open this post in threaded view
|

Re: Transfering Pointcloud from camera coordinate to world coordinate!

koen buys-2
If you already have the segmentation done and you have the centroid, you can just transform the centroid and save you some computation time.


On 5 February 2013 21:38, Nims <[hidden email]> wrote:
When The coordinates are in the world coordinate , is n't the z value of a
point its height?



--
View this message in context: http://www.pcl-users.org/Transfering-Pointcloud-from-camera-coordinate-to-world-coordinate-tp4025867p4025906.html
Sent from the Point Cloud Library (PCL) Users mailing list mailing list archive at Nabble.com.
_______________________________________________
[hidden email] / http://pointclouds.org
http://pointclouds.org/mailman/listinfo/pcl-users


_______________________________________________
[hidden email] / http://pointclouds.org
http://pointclouds.org/mailman/listinfo/pcl-users