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Author Topic: Big coordinates in exported .las-file, how to fix?  (Read 9567 times)

Sky_hie

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Big coordinates in exported .las-file, how to fix?
« on: December 08, 2014, 12:14:47 PM »
Hi.

When importing a .las file created in PS to a las-Viewer program I get very big coordinates. How can I avoid this?

Thanks

SH
« Last Edit: December 08, 2014, 12:50:42 PM by Sky_hie »

Alexey Pasumansky

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #1 on: December 08, 2014, 12:53:16 PM »
Hello Sky-hie,

By default PhotoScan saves point coordinates in the same system that was used for chunk referencing. So if you are using UTM projections big values can be expected.

But in case georeferencing is not required for your tasks, you can use Shift fields in the Export Points dialog to remove the same big  value from all coordinates or even use Local Coordinates.
Best regards,
Alexey Pasumansky,
Agisoft LLC

Sky_hie

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #2 on: December 08, 2014, 01:04:48 PM »
Hello Sky-hie,

By default PhotoScan saves point coordinates in the same system that was used for chunk referencing. So if you are using UTM projections big values can be expected.

But in case georeferencing is not required for your tasks, you can use Shift fields in the Export Points dialog to remove the same big  value from all coordinates or even use Local Coordinates.

I need a georeferenced pointcloud for this task. The external program is having a hard time importing the las file.

Positional data are gathered in WGS and gcp data are in UTM. When exporting Points to las-format I choose ETRS UTM. Is this correct?


Alexey Pasumansky

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #3 on: December 08, 2014, 01:07:15 PM »
Hello Sky_hie,

It seems to be correct. But if you have large values for the Easting and Northing in this system, then I'm not sure that you can avoid it, since you need these values.
Best regards,
Alexey Pasumansky,
Agisoft LLC

Sky_hie

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #4 on: December 08, 2014, 01:16:56 PM »
Hello Sky_hie,

It seems to be correct. But if you have large values for the Easting and Northing in this system, then I'm not sure that you can avoid it, since you need these values.

Please look at the attachment

Sky_hie

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #5 on: December 08, 2014, 01:17:47 PM »
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Alexey Pasumansky

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #6 on: December 08, 2014, 01:22:00 PM »
Hello Sky_hie,

So I see that coordinates of the points in the system used are large. And as I've understood you need to save them in this particular system. That's why I'm little bit confused, how you can used smaller values for the same points and same coordinate system.
Best regards,
Alexey Pasumansky,
Agisoft LLC

Sky_hie

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #7 on: December 08, 2014, 01:31:05 PM »
Hello Sky_hie,

So I see that coordinates of the points in the system used are large. And as I've understood you need to save them in this particular system. That's why I'm little bit confused, how you can used smaller values for the same points and same coordinate system.

Alexey,

So you cannot see any obvious errors/problems in the screenshots?


When importing to external program the coordinates gets even bigger. When importing to AutoCAD I get this: "The Selected Layer States Could Not Be Restored"

Any idea?

 
« Last Edit: December 08, 2014, 01:37:09 PM by Sky_hie »

Alexey Pasumansky

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #8 on: December 08, 2014, 01:37:08 PM »
Hello Sky_hie,

I can suggest to export cropped dense point cloud with small number of points and check if the issue is related to the number of points. Also you can try to export in local coordinates to check if the issue is related to the big values for the coordinates.
Best regards,
Alexey Pasumansky,
Agisoft LLC

Sky_hie

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #9 on: December 08, 2014, 01:52:57 PM »
Hello Sky_hie,

I can suggest to export cropped dense point cloud with small number of points and check if the issue is related to the number of points. Also you can try to export in local coordinates to check if the issue is related to the big values for the coordinates.

Seem to work when I export With local coordinate system and small number of points. I have 150 million Points in this project, do you think this too much for most programs? The las-file is 4.5 GB in size...

Also, is there a way of splitting the cloud in several parts in PS?

Alexey Pasumansky

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #10 on: December 08, 2014, 01:55:43 PM »
Hello Sky_hie,

Unfortunately, I'm not aware of the import limits for AutoCAD.

Dense cloud could be split in blocks on export in PhotoScan version 1.1.0.
Best regards,
Alexey Pasumansky,
Agisoft LLC

Sky_hie

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #11 on: December 08, 2014, 02:08:30 PM »
Hello Sky_hie,

Unfortunately, I'm not aware of the import limits for AutoCAD.

Dense cloud could be split in blocks on export in PhotoScan version 1.1.0.

ok.

I have PS 1.0.4 Professional edition. "There is no update required" Message when checking for updates..

Alexey Pasumansky

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #12 on: December 08, 2014, 02:13:36 PM »
Hello Sky_hie,

Version 1.1.0 is available as pre-release from the sticky topic in General forum section:
http://www.agisoft.com/forum/index.php?topic=2883.0

Alternatively you can vary bounding box size in version 1.0.4 as dense cloud export saves only points inside the box.
Best regards,
Alexey Pasumansky,
Agisoft LLC

Sky_hie

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #13 on: December 08, 2014, 02:19:13 PM »
Hello Sky_hie,

Version 1.1.0 is available as pre-release from the sticky topic in General forum section:
http://www.agisoft.com/forum/index.php?topic=2883.0

Alternatively you can vary bounding box size in version 1.0.4 as dense cloud export saves only points inside the box.

Ok. When will the final be released?

Thank you for the tip With the b-box:)

Also, thank you for the support!

Alexey Pasumansky

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Re: Big coordinates in exported .las-file, how to fix?
« Reply #14 on: December 08, 2014, 02:23:13 PM »
I think that version 1.1.0 will be released in the end of December.
Best regards,
Alexey Pasumansky,
Agisoft LLC