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GRASS r.in.lidar fails in QGIS but works in native GRASS #29740

Closed qgib closed 4 years ago

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson) Original Redmine Issue: 21925 Affected QGIS version: 3.6.2 Redmine category:processing/grass

File info pulled from LAS-file, using GRASS because that function doesn’t work in QGIS!

The data is in "SWEREF 99 18 00", a Swedish coordinatesystem.

Using LAS Library Version 'libLAS 1.8.0 with GeoTIFF 1.4.0 GDAL 1.11.3 LASzip 2.2.0' LAS File Version: 1.2 System ID: 'Trimble' Generating Software: 'TRW 2.21.0 2.2 r0 (130917)' File Creation Day/Year: 234/2018 Point Data Format: 2 Number of Point Records: 126410605 Number of Points by Return: 126410605 0 0 0 0 Scale Factor X Y Z: 0.0001 0.0001 0.0001 Offset X Y Z: 149520 6.56859e+006 20 Min X Y Z: 148852 6.56773e+006 5.0197 Max X Y Z: 149927 6.56905e+006 80.8466 Spatial Reference: None Data Fields: 'X' 'Y' 'Z' 'Intensity' 'Return Number' 'Number of Returns' 'Scan Direction' 'Flighline Edge' 'Classification' 'Scan Angle Rank' 'User Data' 'Point Source ID' 'Red' 'Green' 'Blue'

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

Can you attach sample data?

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

Giovanni Manghi wrote:

Can you attach sample data?

I got one file and it’s to big.

I think the problem can be that there’s no coordinate system info in the file and it works in GRASS because you set up a predefined file and coordinate system that GRASS can assume is the same system as the file. If it was possible to tell QGIS what coordinate system to assume is right then it might work.

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

So I guess the problem is the lack of spatial reference in the file.

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

I got one file and it’s to big.

link?

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

Giovanni Manghi wrote:

I got one file and it’s to big.

link?

https://sprend.com/download?C=e892a43de33f49b79b63c421e4a03ab8

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

What CRS do you use to create your GRASS mapset/location where this data import correctly?

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

Giovanni Manghi wrote:

What CRS do you use to create your GRASS mapset/location where this data import correctly?

CRS EPSG:3011 - SWEREF99 18 00 - Projected

I sett GRASS not to assume any CRS of the data.

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

I sett GRASS not to assume any CRS of the data.

that is not how Processing works when using GRASS tools: as far as I remember a temporary location/mapset is created on the fly while importing the data, and the CRS used is derived from the data itself. Is this the rule for any lidar data, they do not have an intrinsic CRS?

qgib commented 5 years ago

Author Name: Olivier ATHIMON (Olivier ATHIMON)

Is it the same problem than i have ? => #29720

Before we could use functions of GRASS in Processing/GRASS by using the shortcut "QGIS Desktop"? But now, functions of Processing/GRASS only work by using the shortcut "QGIS Desktop with GRASS"...

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

Giovanni Manghi wrote:

I sett GRASS not to assume any CRS of the data.

that is not how Processing works when using GRASS tools: as far as I remember a temporary location/mapset is created on the fly while importing the data, and the CRS used is derived from the data itself. Is this the rule for any lidar data, they do not have an intrinsic CRS?

I think the problem can be that Grass att least needs to know the project CRS to convert the LASfile. Do QGIS create a temporary database/project when processing?

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

Olivier ATHIMON wrote:

Is it the same problem than i have ? => #29720

no, I think the above ticket was already given and answer.

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

Do QGIS create a temporary database/project when processing?

yes, it creates on the fly a mapset/location where it (on the fly) imports the input data, then it process it and export out from the location/mapset. I think it uses the CRS of the input to define the projection for the mapset/location.

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

Giovanni Manghi wrote:

Do QGIS create a temporary database/project when processing?

yes, it creates on the fly a mapset/location where it (on the fly) imports the input data, then it process it and export out from the location/mapset. I think it uses the CRS of the input to define the projection for the mapset/location.

Maybe you could have a optional setting for overriding the files crs?

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

Maybe you could have a optional setting for overriding the files crs?

that would be a feature request.

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

Giovanni Manghi wrote:

Maybe you could have a optional setting for overriding the files crs?

that would be a feature request.

Or a solution to the bug.

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

qgib commented 5 years ago

Author Name: Andreas Olsson (Andreas Olsson)

“ -o Override projection check (use current location's projection) Assume that the dataset has same projection as the current location “ This option is also in QGIS for r.in.lidar but it needs to know the project crs to actually work.

qgib commented 5 years ago

Author Name: Giovanni Manghi (@gioman)

This option is also in QGIS for r.in.lidar but it needs to know the project crs to actually work.

That GRASS options assumes that the data CRS is the same as the mapset/location (that aleady exist). In QGIS the CRS for mapset/location (that does not exist yet) is derived from the data being used as input (again, I think bit not 100% sure).

neteler commented 4 years ago

Could you try with the new GRASS GIS 7.8.1 (https://github.com/OSGeo/grass/releases/tag/7.8.1)? Also projection related issues where fixed and Python 3 is supported since 7.8.0.

And since liblas is rather outdated, an addon we have https://grass.osgeo.org/grass7/manuals/addons/r.in.pdal.html and pending updates here: https://github.com/OSGeo/grass/pull/61 (PDAL-based version of r.in.lidar)

alexbruy commented 4 years ago

Closing for the lack of feedback. Please reopen if necessary.