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rgbdslam: How to get transform between poses?

asked 2012-05-31 22:42:04 -0500

ph4nt0m gravatar image

updated 2014-01-28 17:12:31 -0500

ngrennan gravatar image


I'm trying to learn more about the general concept of rgbdslam. Let's say I found a rigid body transformation (represented by a 4x4 matrix) between two consecutive frames (more precisely, between the feature sets of these, if I understand correctly) by using RANSAC, how can I use this to calculate the transformation that represents the change in pose between these two frames?

Thanks in advance!

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answered 2012-06-01 04:55:39 -0500

updated 2012-06-03 06:11:32 -0500

It is the inverse. The features are in the respective coordinate frames of the camera positions. So a transformation that moves the features from the first camera coordinate system to the second moves the second camera pose to the pose where it was in the first frame.

Edit: Correction.

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But if the camera moves towards some features (so that they come nearer, their z values decrease), then the feature-transform would be one that moves every point in opposite z direction. But the position of the camera itself (seen from a global coord. sys.) would have moved forward in this example.

ph4nt0m gravatar image ph4nt0m  ( 2012-06-01 08:42:55 -0500 )edit

Yes, you are right, it is vice versa.

Felix Endres gravatar image Felix Endres  ( 2012-06-03 06:09:58 -0500 )edit

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Asked: 2012-05-31 22:42:04 -0500

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