Height Field vs. Arbitrary

[sarko]

Hello,

I have posted on this topic before, but am hoping someone perhaps has figured it out.  I use a lot of historic imagery and occasionally have problems generating height fields.   I have attached three images showing a dense point cloud, arbitrary mesh, and height field mesh.   As you can see, the dense cloud looks good, as does the arbitrary mesh.  The height field mesh looks horrible, however.  This may not be the best example since it is in a highly glaciated region and many areas are void due to saturation in the input imagery, however, I have seen this issue in other non-glaciated regions as well.  A couple things I have tried:

1.  Used gradual selection to try to eliminate lower quality points in sparse cloud -- no impact
2.  Cropped the edges of the dense cloud thinking that this was an edge effect.  I even cropped to only an interior region as far away from edges as I could. -- no impact
3.  Tried various options for the number of points calculated and maximum tie points retained -- no impact

It seems as though this is happening more often, but it may just be the data I'm using of late.

I have posted a tar ball of the project file and raw data scans here:

https://akarise.asf.alaska.edu/photoscan/BlackRapids.tar.gz

The screen caps were from my MacBook Pro, but I see the same problem on my primary processing system, which is Windows.  I am using the latest stable release of Photoscan Professional. 

Any suggestions would be greatly appreciated. 

[James]

You need to rotate the bounding box region so that the 'red' face is aligned with ground, and at the bottom of the model. This defines the direction in which 'height' of the height field is calculated.

[sarko]

Hi James.  Huh, this is not meant to sound rude, but there is a red side??  I am terribly color blind and never realized the sides of the bounding box were colored.   If that is really the answer, thank you so much.  This problem has intermittently troubled me for some time now. 


 

[James]

It's very subtle! In your 3rd screen shot it is the face bottom most in the image, and at the right hand side there is a little (as in tiny) line on the rightmost adjacent face which points straight up, and which you should orient to point towards the real world up direction.

*edit, it's on all 3 of your screenshots in fact

[andyroo]

Maybe would be good suggestion to Agisoft to make bounding box white with black ground (or pick a colorblind-friendly palette) so colorblind folks can see the difference. I always try to use colorblind-friendly palettes with color graphs because so many scientists/engineers have that feature.

[bigben]

Or making the corner handles for the bottom darker/black

[gatsri]

Or just take this python-script to rotate the Boundingbox to coo-sys.

http://wiki.agisoft.com/wiki/Coordinate_System_to_Bounding_Box.py

[Wishgranter]

Sarko, read email...