Combining .pcd files

Hello! I'm trying to stitch (hope that's the right word) together several (>20) .pcd files together from a program called Blensor.

From what I understand, the .pcd format assumes an origin and then plots offset XYZ (and RGB values) relative to an arbitrary origin. So in order to get around this, I exported the motion (deltaX, deltaY, deltaZ) of the camera object that generates the data.

Now, I'm left with around 20 .pcd files bound to an arbitrarily positioned origin, and I need to use the offset values that I've gotten from the motion file, and somehow set that as the origin of each individual point cloud and then combine them.

All coordinates are cartesian (X,Y,Z), and assumed to be metric. Can anyone help me?

[Kevin Gleason]

Having never used blensor, what is the contents of each individual PCD file? Also what does a PCD image (exported as link below) give you, and what would the stitched together example look like?

http://www.blensor.org/node/24

Looking for a bigger picture example so I don't answer the wrong question

[Andrew Schroeder]

Hey Mr. Gleason, thanks for your help!

The PCD file contains a list of values of X, Y, Z, RGB, and Object Number (the last two which I don't need).

These are relative to a location in cartesian points that the center of the camera object was at when the scan was run along with the rate of change of rotation along XYZ axes.

I'm assuming that I need to set a series of nested for-loops that calculate the location of each point in space relative to the origin, which would give me points like [x0 + x1, y0 + y1, z0 + z1] assuming that the x0, y0, and z0 are the cameras offset relative to the origin, and x1, y1, and z1 are distances relative to the camera.

After that, I believe that I may be able to just vertically concatenate the series of files into a matrix and plot from there, essentially eliminating the need to stitch point clouds together.

Does that make any sense? At this point, I'm not so sure anymore...

Thanks for any help you can give me!