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E57 to LAS with time and station ID


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I'm trying to convert an ASTM e57 file to LAS, and retain the e57 station IDs as the LAS Point Source ID attribute. Is there a way to do this? Thanks!

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Best answer by trentatsafe 28 July 2017, 20:00

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Hello @wolfsnipes

You should be able to write the E57 station IDs to the LAS Point Source ID component, aslong as the values are between 0-65535. It should be noted that with having the Station IDs as an attribute, you will need to use a PointCloudComponentAdder or similar transformer, to convert the attribute to a component.

 

 

I hope that helps.
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Thanks @trentatsafe!

Is it also possible to do this with timestamps on a per laser shot record basis? LAS file often have a timestamp per pulse, and if the E57 file has this can this be converted? I didn't see an attribute for this in the FME data model...but am pretty new to FME so might have missed it somehow.

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Thanks @trentatsafe!

Is it also possible to do this with timestamps on a per laser shot record basis? LAS file often have a timestamp per pulse, and if the E57 file has this can this be converted? I didn't see an attribute for this in the FME data model...but am pretty new to FME so might have missed it somehow.

Hi @wolfsnipes

 

I believe this is possible. There is a component, gps_time, that can be used to write the time attribute. Again you would need to convert the attribute to a component using the PointCloudComponentAdder transformer and set the component as gps_time and the value to the time attribute you have. Ensure the data type is also correct. Here is some of our documentation regarding the gps_time component: https://docs.safe.com/fme/html/FME_Desktop_Documentation/FME_ReadersWriters/las/Feature_Representation.htm

 

 

I tested this with a 'DateTimeStamper" transformer before converting this attribute to a component and was able to write the component to a LAS file.

 

 

I hope that helps.

 

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Hi @wolfsnipes

 

I believe this is possible. There is a component, gps_time, that can be used to write the time attribute. Again you would need to convert the attribute to a component using the PointCloudComponentAdder transformer and set the component as gps_time and the value to the time attribute you have. Ensure the data type is also correct. Here is some of our documentation regarding the gps_time component: https://docs.safe.com/fme/html/FME_Desktop_Documentation/FME_ReadersWriters/las/Feature_Representation.htm

 

 

I tested this with a 'DateTimeStamper" transformer before converting this attribute to a component and was able to write the component to a LAS file.

 

 

I hope that helps.

 

Right...but does this exist in the E57 format, which I am converting from? All I see available is this (with the rest being rowindex/columnindex/cartesianinvalidstate):

 

Thanks for your help @trentatsafe
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Right...but does this exist in the E57 format, which I am converting from? All I see available is this (with the rest being rowindex/columnindex/cartesianinvalidstate):

 

Thanks for your help @trentatsafe
Hi @wolfsnipes

 

It does appear that E57 may house this data from looking at our documentation: https://docs.safe.com/fme/html/FME_Desktop_Documentation/FME_ReadersWriters/e57/Feature_Representation.htm

 

Most notably for the Point cloud geometries: acquisition_start/acquisition_end I believe may be the traits you are looking for.

 

If you have some sample data I could take a look at it.

 

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