[pdal] losing precision in PDAL pipeline

[Andrew Bell]

This is caused by a bug that writes metadata for LAS scale/offset with
excess precision.  I've opened this issue to address the problem:
https://github.com/PDAL/PDAL/issues/2663

On Thu, Aug 8, 2019 at 11:55 AM Andrew Bell <andrew.bell.ia at gmail.com>
wrote:

> I suspect the scale of your input files differs. If this is the case, the
> scale values aren't forwarded. You'll have to set them manually.
>
> ,
>
> On Thu, Aug 8, 2019, 11:29 AM Karl North <karln at surdex.com> wrote:
>
>> Good morning once again PDAL’ers.  It’s a new day, and a new issue…
>>
>>
>>
>> I’m running a multi-step process using several executions of “pdal
>> translate” and at the end assembling the various parts ( multiple LAS files
>> ) from these executions into a final point cloud ( LAS file ) for
>> delivery.  All of the “pdal translate” commands include the string :
>> --writers.las.forward="all" in order to preserve the precision of the
>> source data.
>>
>>
>>
>> My problem is that at the final step where I use “pdal pipeline” to merge
>> the various parts, my file precision gets truncated from 0.001 to 0.01
>> units.
>>
>>
>>
>> Below is a simple minimalist sample JSON file that I am running through
>> “pdal pipeline” to do the merge operation.  I have checked and all the
>> input LAS files have 0.001 precision but the output LAS has only 0.01
>> precision.  I expected the forward=all line to preserve scales and offsets.
>>
>>
>>
>> Please help.  What am I missing?
>>
>>
>>
>> {
>>
>>     "pipeline":[
>>
>>         {
>>
>>             "type":"readers.las",
>>
>>             "tag":"WT_4447_596_step01b",
>>
>>             "filename":"WT_4447_596_step01b.las"
>>
>>         },
>>
>>         {
>>
>>             "type":"readers.las",
>>
>>             "tag":"WT_4447_596_step02",
>>
>>             "filename":"WT_4447_596_step02.las"
>>
>>         },
>>
>>         {
>>
>>             "type":"writers.las",
>>
>>             "inputs":["WT_4447_596_step01b","WT_4447_596_step02"],
>>
>>             "forward":"all",
>>
>>             "filename":"WT_4447_596_step03.las"
>>
>>         }
>>
>>     ]
>>
>> }
>>
>>
>>
>> Karl
>>
>>
>> _______________________________________________
>> pdal mailing list
>> pdal at lists.osgeo.org
>> https://lists.osgeo.org/mailman/listinfo/pdal
>
>

-- 
Andrew Bell
andrew.bell.ia at gmail.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/pdal/attachments/20190808/c5c458b3/attachment.html>