Hi:
I have two static points in the capture volume of the camera. (approximately in the middle). In the preview mode of the calibration tool, I can see both points in all the three cameras, and the software correctly report 2 objects in each of them. However, in the result mode, I get inconsistent results in the camera rays output: sometimes one camera doesn't see the points; if I go to the preview mode and the back to the result mode, then the camera that wasn't seeing the points now see the points, but another camera doesn't see them.
Any comments?
My system is:
-Laptop Fujitsu Lifebook T series
-Windows XP SP2
-Three C120 cameras connected directly to the Laptop (no hub)
-Pointcloud toolkit version 1.1.032
Inconsistent camera rays output
Re: Inconsistent camera rays output
So you are running the calibration, with the 2 points being detected as well?
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aweinstein
- Posts: 27
- Joined: Fri Oct 26, 2007 9:43 am
Re: Inconsistent camera rays output
[quote=NaturalPoint - Vincent]So you are running the calibration, with the 2 points being detected as well?
[/quote]
Don't quite understand your question. First I do the calibration process, according to the procedure. Then, I want to test the accuracy of the system. For this, I load the calibration file previously generated, and then place two points at a known distance. I select the camera rays option, to see if the cameras are seeing the points. At that moment I get the inconsistent behavior I mention before.
[/quote]
Don't quite understand your question. First I do the calibration process, according to the procedure. Then, I want to test the accuracy of the system. For this, I load the calibration file previously generated, and then place two points at a known distance. I select the camera rays option, to see if the cameras are seeing the points. At that moment I get the inconsistent behavior I mention before.
Re: Inconsistent camera rays output
How close to the cameras are you placing the 2 points?
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aweinstein
- Posts: 27
- Joined: Fri Oct 26, 2007 9:43 am
Re: Inconsistent camera rays output
[quote=NaturalPoint - Vincent]How close to the cameras are you placing the 2 points?[/quote]
Around 1.5 meters.
Around 1.5 meters.
Re: Inconsistent camera rays output
Alejandro,
The reason you are seeing inconsistent camera rays is basically because you're using the C120s. The error induced by the relatively low resolution sensor on the C120 combined with the lens distortion cause the camera ray to diverge far enough away from the other camera rays that the point cloud library rejects the ray as being associated with the marker.
Two things can improve this:
- V100 camera don't have this problem because of their significantly higher quality output.
- In the calibration tool you have the ability to adjust some of the point cloud library parameters while previewing the calibration result in 3D. If you override the default parameters increase the 'residual' value, this allows there to be more error in the camera rays without rejecting them. And you will magically see a proper correlation.
Hope this helps,
Doug
The reason you are seeing inconsistent camera rays is basically because you're using the C120s. The error induced by the relatively low resolution sensor on the C120 combined with the lens distortion cause the camera ray to diverge far enough away from the other camera rays that the point cloud library rejects the ray as being associated with the marker.
Two things can improve this:
- V100 camera don't have this problem because of their significantly higher quality output.
- In the calibration tool you have the ability to adjust some of the point cloud library parameters while previewing the calibration result in 3D. If you override the default parameters increase the 'residual' value, this allows there to be more error in the camera rays without rejecting them. And you will magically see a proper correlation.
Hope this helps,
Doug