Help with oblique imagery - setting up the Cameras table

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08-10-2016 02:08 AM
FilipJung
Occasional Contributor

Hi,

I would like to test the Oblique viewer sample and for that I need to prepare the Mosaic Dataset and publish it. I have found some sample datasets here: https://www.sensefly.com/drones/example-datasets.html

I have tried the sample called "Oblique imagery"

I created and populated Cameras and Frames tables and created Mosaic Dataset using these tables. Rasters are loaded, but the distortion parameteres seem to be not set up properlly because Footprints looks unreal:sullens_mosaic_dataset.PNG

My Camera table looks like:

OBJECTIDCAMERAIDFOCALLENGTHPRINCIPALXPRINCIPALYA0A1A2B0B1B2SRSKonradyDistortionType
1[0]5387.47722-66.31365315.2541-3720.1697251.8605502789.8947250-1.8605326320;-0.00018232164051963605;-5.1623376542584604e-006;1.235913254591796e-007Esri-Konrady

My Frames table sample is:

OBJECTIDOmegaPhiKappaSRSCameraIDNColsNRowsNBandsPixelTypeRasterPerspectiveXPerspectiveYPerspectiveZ
145.899019-7.362863175.28971732632[0]4000300038_BIT_UNSIGNED...\IMG_7719.JPG313636.6989785162861.933003714.078282
245.912378-2.495157171.89343232632[0]4000300038_BIT_UNSIGNED...\IMG_7720.JPG313643.4415095162858.355595713.06864

Can anyone please check my values?

Thanks in advance.

Filip

11 Replies
ModyBuchbinder
Regular Contributor II

Hi Filip

I do not know the answer to your question but I have many image services and very interest to get what you see in the screen shot.

Your link to the sample does not work but I found it any way. It does not have too much information. Can you explain what you did to get to the screen shot?

Thanks

Mody

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FilipJung
Occasional Contributor

Hi Mody,

the correct link is: https://www.arcgis.com/home/item.html?id=d91008d8ca85490ab423715a16d63527

Sorry for that and thank for your answer.

What can be seen on screenshot is a view on Mosaic dataset footprints in ArcMap with one raster loaded using Add Selected Rasters to Map function.

I did it to try viewing the image in Image Coordinate System using instructions from here: Displaying Images in an Image Coordinate System—Help | ArcGIS for Desktop

For some images, I can get the good preview in ICS (please see below), but for some not. I believe there is a problem in Camera or Frames table, that generates these unreal footprints.

I will doublecheck the values as Cody poposes.

_imagePreview.png

Regards.

Filip

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CodyBenkelman
Esri Regular Contributor

Filip

Sorry I didn't answer earlier; I am seeking to verify this with our engineers but we haven't had time to review your data in detail.  It appears to me that your configuration is nearly correct, but something is scaling the values to be much too large.  I posted earlier (incorrectly) that I believed the PerspectiveZ may be height above ground, but I have since verified that it should represent Orthometric height.  (We are working to clarify the documentation for this table to ensure it is clear how the Z values are defined.)

I'll review in the next day or two if time permits, but please verify units for parameters in both the camera and frame tables; I know that there are some mixed units (microns and millimeters), so I expect you have a value in microns that should be mm, and that is causing the scale errors.

Cody B

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FilipJung
Occasional Contributor

Hi

I have checked the values in tables and they should be OK. I have only doubts about Matrix att in Frames table (please see below).

Cameras table:

FocalLength - I converted from milmeters to microns (from internal_camera_parameters.cam file)

PrincipalX - I converted from value Px in milmeters to microns (from internal_camera_parameters.cam file)

PrincipalY - I converted from Py in milmeters to microns (from internal_camera_parameters.cam file)

Coefficients A0, A1, A2, B0, B1, B2 were calculated using formulas from here:

http://proceedings.esri.com/library/userconf/devsummit16/papers/dev_int_237.pdf (page 9), or this image taken from that document:

_camera_coeffs.png

As input I used:

PixelSize [microns] 1.86055 - calculated assuming 4000x3000 image pixels image and converted from sensor width in milimeters in internal_camera_parameters.cam file

SenzorWidth [microns] 7442.2 - calculated and converted from sensor width in milimeters in internal_camera_parameters.cam file

SensorHeight [microns] 5581.65 - calculated and converted from sensor width in milimeters in internal_camera_parameters.cam file

Frames table:

PerspectiveX - values in meters (SRS = 32632)

PerspectiveY - values in meters (SRS = 32632)

PerspectiveZ - I believe that it is in WGS84 Ellipsoidical height or Orthometric height - meters

Omega - in degrees

Phi - in degrees

Kappa - degrees

NCols - in pixels = 4000

NRows - in pixels = 3000

Matrix - I have found out that I dont have this field in my table. In params folder of sample data I used is pmatrix.txt file, which contains image name and 12 floating point values. The Frames table documentation states only 9 values. Can these values be used? Or do I have to left the fourth value in every row? The documentation of pmatrix file is avilable here:

https://support.pix4d.com/hc/en-us/articles/202977149-What-does-the-Output-Params-Folder-contain-#la...

Is it Required if Camera uses OrientationType = OPK (default)??

Thanks for help. Regards.

Filip

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FilipJung
Occasional Contributor

Hi Cody.

Have you had a time to take look at the data sample? Thanks.

Filip

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CodyBenkelman
Esri Regular Contributor

Hi Filip - sorry, no.  I am on vacation and have not had time to look at this.  I will contact one of my colleagues and ask them to respond.

Cody B.

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FilipJung
Occasional Contributor

Hi Cody,

hope you had a pleasant vacation. Have you or any of your colleagues time to look at the data? Thank you.

With regrads

Filip

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MattiasTivlin
New Contributor II

Hi

How did you create the camera table and frame table? Did you use an third-party sw like pix4d to export the parameters?

Have you tried this with own drone images?

It been a while since you posted so i'm trying to do this in arcgis pro

Regards Mattias

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CodyBenkelman
Esri Regular Contributor

Mattias

Presuming that you have interior and exterior orientation data in another format, this geoprocessing tool is designed to create the tables needed by ArcGIS Pro:

Build Frames and Cameras Tables Tool—ArcGIS Pro | Documentation 

If you don't have the interior and exterior orientation data, generating that orientation data is a different challenge. 

Ortho Mapping in ArcGIS Pro (Advance license) can also do this automatically as long as the oblique orientation is not too extreme (closer to nadir, not aimed at horizon), and it will directly create a mosaic dataset for you (you don't need to create the two tables).

If you don't have ArcGIS Pro Advance license Yes, Drone2Map or Pix4D can create the interior and exterior orientation data  

Cody B.