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question about projectpixelto3dray

asked 2012-09-17 00:06:59 -0600

Alberto Martín gravatar image

updated 2012-09-17 02:01:32 -0600

Lorenz gravatar image


I have a question about the function projectPixelTo3dRay, according to the API the return value is a 3d ray passing through (u,v).

But what does that mean? Why Z is 1? How I can calculate the point where it intersects the ray with the floor (Z = 0)?


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Thanks domhege, but how I can transform between the camera system and the system floor? you know any example?

Alberto Martín gravatar image Alberto Martín  ( 2012-09-17 04:12:52 -0600 )edit

Use the tf library. Obviously someone, somewhere must compute this transformation, i.e. where is the camera relative to the floor.

dornhege gravatar image dornhege  ( 2012-09-17 05:00:32 -0600 )edit

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answered 2012-09-17 02:39:42 -0600

dornhege gravatar image

I think those are camera coordinates, Z=0 does NOT equal floor. Z=0 should equal the origin of the pinhole camera model.

You will need to transform between the camera system and whatever system you have that defines where the floor is.

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Asked: 2012-09-17 00:06:59 -0600

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Last updated: Sep 17 '12