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Are my findings about tod_training correct?

asked 2011-03-25 06:22:48 -0500

Julius gravatar image

I am working on getting a good understanding of the tod_training pipeline and especially the use of the pose estimations. Please correct me if I am wrong.

Step 1: Pose estimation -- For each object and view, the pose is estimated from fiducial markers. The pose describes the orientation of the training object with respect to the camera.

Step 2: Masking -- For each object and view, the point cloud belonging to the training object is separated from the background by point cloud segmentation. The pose estimation from step 1 is crucial for this stage, as it determines the pose a fixed-sized box. All the points in this box are said to belong to the object after removing outliers, and all other points outside of this box are no longer of interest. The mask is generated by perspective projection using camera information.

Step 3: Feature detection and extraction -- For each object and view, features are detected and extracted from the ROI in the 2d gray-scale training images. There is one Features2d produced which contains keypoints and the corresponding generated feature descriptors, and finally the estimated pose. This stage does not use pose information.

Step 4: Features3d creation -- For each object and view, this stage creates an association of keypoints in the training images and corresponding 3d points in the point cloud. This creates a one-to-one mapping between 2d keypoints and 3d points.

Therefore, we should be able to replace steps 1, 2 in case we are able to supply pose estimation from another source than fiducial markers.

(Using object_detection in SVN revision 50425).

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If someone deleted my post, it would still be nice if I knew for what reason. Otherwise, I'll just assume there is someone trying to remove my post "just for fun". I did not intend this post to be for long discussions, just yes/no answers. Anyway, I now posted this on the mailing list as well for I do not know whether this post will be deleted again.
Julius gravatar image Julius  ( 2011-03-29 00:41:47 -0500 )edit
Sorry, your last two posts were very similar on first glance. I thought that you had accidentally double posted.
tfoote gravatar image tfoote  ( 2011-03-29 04:34:43 -0500 )edit
Now I understand. Never mind.
Julius gravatar image Julius  ( 2011-03-29 18:57:05 -0500 )edit

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answered 2011-03-30 04:32:57 -0500

dlmypr gravatar image

1) Pose estimation: The pose is not related to the object it is the pose of the fiducial marker coordinate frame w.r.t. camera frame. ( am using an older svn so not sure if they changed this but be careful. In my svn version the object pose is found in detection not in training. )

2) Perfectly true.

3) Yes indeed.

4) yes.

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Asked: 2011-03-25 06:22:48 -0500

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Last updated: Mar 30 '11