Messages

1

General / clarification on gradual selection parameters please

« on: October 08, 2012, 10:37:54 PM »

Hi there, I am looking for some guidance on the best use of the gradual selection properties to select and delete noisy points after the 'align photos' process with version 0.9.0.

Say, for example, that after I align photos, the chunk info shows the reprojection error to be 0.379438 with a max of 1.1552. What are the units on these values? Are these RMS errors? Is the first number the average?

Given those numbers, what's a statistically reasonable number to choose for selecting points in the gradual section dialog based on reprojection error? When the window pops up, the value in the level field is 0.681566. How was that value calculated?

Likewise, what are the units on the reconstruction uncertainty?

Sure, I can move those sliders around until I get a selection that 'looks right', but I am dealing with uneven terrain. I don't really know which points have been correctly located and which have not. It introduces user bias. I would be happier if there was a way to select, for example, only points that fall within a 95% confidence interval.

Thanks

2

General / Re: Photoscan with Old Aerial Photos

« on: August 15, 2012, 09:46:24 PM »

Thank you Matt and Diego,
I will look into those. In the meanwhile, could either of you, or anyone else, explain the problems, if any, in simply "georeferencing" the images to the pixel coordinate space by assigning the calibration-derived coordinates of the fiducials, in ArcMap for instance, to the fiducials and exporting a rectified image? Is that basically the process in interior orientation? Although, automating that process for many photos, I presume, would require some kind of image recognition algorithm to find the fiducial marks?

On the other hand, I just ran some old photos though PS after only specifying the focal length and got much better results, maybe good enough. Perhaps that's all the pre-processing I have to do; I would have to run some tests.

3

General / Re: Photoscan with Old Aerial Photos

« on: August 08, 2012, 01:55:23 AM »

Hey Matt,
What program are doing the interior orientation with?
And is your cropping to fiducials an automated or manual process?

4

Python and Java API / Re: PS not recognizing GPSAltitude tag

« on: June 12, 2012, 10:50:02 PM »

Ok, thanks. Actually it was just couple more lines of code to write out a text file from which the XYZ are imported just fine.

5

Python and Java API / PS not recognizing GPSAltitude tag

« on: June 05, 2012, 10:24:39 PM »

I am geotagging photos through a python script. PS recognizes the lat and long tags but it always imports 0 for the Altitude. When I look at the tags in Irfanview, the altitude is interpreted correctly, so it would appear that it's getting written correctly. An example and the script is attached. Any suggestions?

6

Python and Java API / Error when specifying filter_mask argument in alignPhotos

« on: May 30, 2012, 03:49:59 AM »

This line of code:

Code: [Select]

chunk.alignPhotos('high', 'ground control', True)
returns this error:

Code: [Select]

RuntimeError: more argument specifiers than keyword list entries (remaining format:'i')
Using:

Code: [Select]

chunk.alignPhotos('high', 'ground control') works, but I really want to be able to filter by masks.

I am using version 0.8.5
Any suggestions?

7

General / Re: Decimation

« on: May 23, 2012, 07:35:39 PM »

When you go to the decimate mesh dialog, how does PhotoScan arrive at the suggested number of faces? And at this point, when making DEMs, how do I know what the resolution of a resulting DEM will be if I go ahead and decimate to that number?

8

Feature Requests / decimate by percent

« on: May 09, 2012, 03:15:08 AM »

For when I set up batch processes to run overnight, it would be nice to decimate by a percentage rather than specifying a specific number of faces when I don't know what the total will be after I build geometry.

9

Feature Requests / Re: create chunk from selected photos

« on: April 30, 2012, 09:59:28 PM »

Thanks for the tip! That's great.

10

Feature Requests / create chunk from selected photos

« on: April 26, 2012, 09:03:26 PM »

I have been making chunks by duplicating a 'template' chunk that contains all of the photos in my project and then deleting the photos I don't want to use for the current chunk. But it would be more intuitive for me to be looking at the locations of photos in my template chunk, select the ones I want to use, and have an option to 'create chunk from selected photos'.

An alternative would be to have the Edit > Invert Selection enabled for photo locations. I could make my selection for a chunk, invert, and then delete.

11

General / Re: Settings of photos in Ground Control window

« on: April 26, 2012, 08:13:29 PM »

Thanks Alexey. That's what I was thinking. One more thing, if there are photos with registration errors that are so bad that I want to remove them from the georeferencing, does it follow that I would probably want to disable them from building geometry? Does the registration error propagate into the geometry?

12

General / Settings of photos in Ground Control window

« on: April 25, 2012, 08:28:51 PM »

In the Photos pane of the Ground Control window with 'View Source' checked, what exactly are the uses of the options in the right-click context menu? That is, whether photos are enabled, disabled, checked, unchecked, and whether I delete the XYZ fields or leave them with values?

13

Feature Requests / Re: Export in LAS format

« on: April 23, 2012, 09:07:03 PM »

So, it does! Beg your pardon.

14

Feature Requests / Export in LAS format

« on: April 19, 2012, 03:54:58 AM »

For easier integration with GIS (ArcGIS 10.1 will supposedly have native support for LAS datasets) and open source LAS viewing, editing, and classification tools, it would be great if we could export a dense point cloud in LAS format.

15

General / Re: orthophoto doesn't look as good as texture

« on: April 17, 2012, 07:56:22 PM »

Right, that's a possibility. Everything I am making in PS will ultimately be used in a GIS.