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Author Topic: Can't build Dense Point Cloud  (Read 9506 times)

gregdowning

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Can't build Dense Point Cloud
« on: April 09, 2015, 04:56:18 AM »
I am using version 1.1.5, I have 149 images that look well calibrated and when I try to build a dense point cloud I am getting the error "Can't build Dense Cloud" I searched the forums and have tried cropping the point cloud to make sure that there are not any points too far out and tried turning my video card off in the Open CL settings as well as restarting the application. The problem persists.

I copied this from the console:
Code: [Select]
[font=courier]Using device: Quadro K4000, 4 compute units, 3072 MB global memory
  max work group size 1024
  max work item sizes [1024, 1024, 64]
  max mem alloc size 768 MB
Initializing...
initializing...
selected 0 cameras from 149 in 0.007 sec
Loading photos...
loaded photos in 0 seconds
Reconstructing depth...
finished depth reconstruction in 0.001 seconds
Device 1 performance: 0 million samples/sec (CPU)
Device 2 performance: 0 million samples/sec (Quadro K4000)
Generating dense point cloud...
selected 0 cameras in 0.001 sec
Finished processing in 0.145 sec (exit code 0)
>>> [/font]

bigben

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Re: Can't build Dense Point Cloud
« Reply #1 on: April 09, 2015, 09:07:17 AM »
"selected 0 cameras from 149"

That'll do it.

Possibly not enough good quality points between images to build a dense cloud?  How many images aligned?  Did you overdo the gradual selection and removal of bad points?

Marcel

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Re: Can't build Dense Point Cloud
« Reply #2 on: April 09, 2015, 10:57:28 AM »
How many points are in your Sparse Cloud, and what Tie Point setting did you use during the alignment (Tie Points are under Advance Settings in the alignment window)?

gregdowning

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Re: Can't build Dense Point Cloud
« Reply #3 on: April 10, 2015, 02:01:55 AM »
All 149 image aligned. It looks correct. There are not any clearly idetifiable bad points to remove. I simply cropped it to the area of interest. There are about 1774 points generated in the sparse point cloud. In the Advanced setting I have Keypoint limit set to 500 and Tie point limit set to 100

gregdowning

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Re: Can't build Dense Point Cloud
« Reply #4 on: April 10, 2015, 02:42:27 AM »
thanks for the help guys, this was clearly the problem, my tie points and keypoints got changed from the default, I don't remember changing them but when I set it to 5000 and 1000 I got my dense cloud.

Marcel

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Re: Can't build Dense Point Cloud
« Reply #5 on: April 10, 2015, 10:29:02 AM »
Glad to hear you found the problem.

I would set the Key Points to 40.000 and the Tie Points to 0. Your alignment will take a bit longer (but not excessively long), but it will be more accurate. Setting Pre-selection to "Generic" speeds up the alignment and generally has no downsides.