SWEREF99 TM GCP problem

Hi,
I’m having problems when using the webodm GCP interface.

I’ve built my GCP file but when i try to use it in the interface i get the following error message:
“Unknown projection EPSG:3006, please use a proj.4 string or UTM (for example, “WGS84 UTM 11N”) to define the projection.”

EPSG 3006 is the right one for Sweref99 TM but it wont accept it…

The GCP file looks like this:
EPSG:3006
gcp01,6165572.994,379245.161,5.736
gcp02,6165584.222,379248.615,5.713
gcp03,6165580.936,379261.789,5.656
gcp04,6165569.103,379258.240,5.663
gcp05,6165567.797,379242.798,5.777

If i cant use the EPSG code then what should the header say in my case??

I really need to use Sweref99 TM for this project…

Sorry for my stupid rookie question but i’ve searched the web with no luck…
Really hope for some help here :slight_smile:

//Andy

Try with:

+proj=utm +zone=33 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs 
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We’re working on supporting more EPSG codes directly.

If it doesn’t work, as Piero mentioned, try the PROJ4 code for now.

A great resource for this is epsg.io

Thank you so much for your respons :slight_smile:

Well… To begin with the string you provided was working, the software was ok with it but the GCP’s was placed in the indian ocean outside Somalia and i know that it shoud be outsid Malmoe in Sweden… :slight_smile:
The GCP’s was captured using Leica professional equipment and in Sweref99 TM, and the GCP’s was measured by a guy who works full time with measuring so im pretty confident that the coordinates are right!
But how do i know that the string you provided corresponds to Sweref99 TM??
Using EPSG code is pretty straight forward, its easy to find what code to use, but theese strings are a mystery to me… :joy:

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Thanx for the tip :slight_smile:

This is what i found on the site you recomended:

EPSG:3006

SWEREF99 TM

Share on: T Q

Transform Get position on a map

Available transformations

  • Sweden - onshore and offshore. , accuracy 1.0 m, code 1879 (default) [grid]

Selected transformation

Method: Geocentric translations (geog2D domain)

Remarks: Parameter values taken from SWEREF to ETRS89 (1) (code 1878) assuming that ETRS89 is equivalent to WGS 84 within the accuracy of the transformation.

Information source: OGP

Revision date: 2002-09-19

Attributes

Unit: metre

Geodetic CRS: SWEREF99

Datum: SWEREF99

Ellipsoid: GRS 1980

Prime meridian: Greenwich

Data source: OGP

Information source: Lantmateriverket (National Land Survey of Sweden). http://www.lantmateriet.se

Revision date: 2010-03-01

Scope: Medium and small scale topographic mapping.

Remarks: From 2003 replaces RT90 2.5 gon V (CRS code 3021). For large scale applications see CRS codes 3007-18.

Method: Geocentric translations (geog2D domain)

Area of use: Sweden - onshore and offshore.

Coordinate system: Cartesian 2D CS. Axes: northing, easting (N,E). Orientations: north, east. UoM: m.

[

Covered area powered by MapTiler MapTiler logo

](https://www.maptiler.com/)

Center coordinates
609924.45 6877630.37

Projected bounds:
181896.33 6101648.07
864416.00 7689478.31

WGS84 bounds:
10.03 54.96
24.17 69.07

Sweden - onshore and offshore.

Sorry that i split the awnser in two, this code was further down on the site:

PROJCS[“SWEREF99 TM”,
GEOGCS[“SWEREF99”,
DATUM[“SWEREF99”,
SPHEROID[“GRS 1980”,6378137,298.257222101,
AUTHORITY[“EPSG”,“7019”]],
TOWGS84[0,0,0,0,0,0,0],
AUTHORITY[“EPSG”,“6619”]],
PRIMEM[“Greenwich”,0,
AUTHORITY[“EPSG”,“8901”]],
UNIT[“degree”,0.0174532925199433,
AUTHORITY[“EPSG”,“9122”]],
AUTHORITY[“EPSG”,“4619”]],
PROJECTION[“Transverse_Mercator”],
PARAMETER[“latitude_of_origin”,0],
PARAMETER[“central_meridian”,15],
PARAMETER[“scale_factor”,0.9996],
PARAMETER[“false_easting”,500000],
PARAMETER[“false_northing”,0],
UNIT[“metre”,1,
AUTHORITY[“EPSG”,“9001”]],
AUTHORITY[“EPSG”,“3006”]]

How do i implement this code into my GCP file?
Do i just put it above the GCP and coordinate list?

Most thankfull for respons :slight_smile:

1 Like

Actually, you grabbed the WKT representation, which won’t work for us.

You need the PROJ4 string:
http://epsg.io/3006.proj4?download

+proj=utm +zone=33 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs 

And yes, it goes as-is as the first line of the gcp_list.txt, just where you’d put the EPSG:3006

Thank you!

Now i have no problems with getting the GCP file to “work” BUT! The projection still isent right…
The interface accepts the projection but places the GCP’s all wrong…

The GCP’s are placed in the indian ocean and they should be in south of sweden.

I have dubble checked the GCP coordinates an the are right, i’ve tryed to enter the coordinates into a map service and then they are placed exactley were they should (in the south of sweden)

But for some reason GCP interface puts them i the south ocean for some reason i dont understand!

As seen below i use the PROJ4 string:
+proj=utm +zone=33 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs
gcp01 6165572.994 379245.161 5.736
gcp02 6165584.222 379248.615 5.713
gcp03 6165580.936 379261.789 5.656
gcp04 6165569.103 379258.240 5.663
gcp05 6165567.797 379242.798 5.777

But still no luck with the placement

image

as you can see in this picture, when i enter the coordinates to try the map service will show them exactley where they should be (right above the city of Malmö, the red circle)
So i know the coordinates are just fine and i know that they are in SWEREF99 TM

The GCP file just added to last reply from me is TAB separated , diden’t realy show in the text content…

image

Here you can see where GCP interface puts my GCP’s

Does this look better?
image

I created it using GCP Editor Pro and making sure it met the specifications for gcp.csv and gcp_list.txt

Try importing this as a gcp.csv and then going from there:

EPSG

+proj=utm +zone=33 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs

gcp.csv

GCP Label,Y,X,Z
gcp01,6165572.994,379245.161,5.736
gcp02,6165584.222,379248.615,5.713
gcp03,6165580.936,379261.789,5.656
gcp04,6165569.103,379258.240,5.663
gcp05,6165567.797,379242.798,5.777

image

Thank you so mutch for all your efforts! :slight_smile:

This looks perfekt!!
Seems like the GCP editor pro works better with SWEREF99 TM then…

So i guess this evening will be spent with installing and getting GCP editor pro working… :sweat_smile:

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