2

I have a similar issue that reported here: R lidR does not read the CRS of my las file. lidR cannot read the CRS while lasinfo from lastools can.

readLAS("USGS_LPC_MS_Tupelo_UTM15_2015_15RYQ605365_LAS_2016.laz")
#> proj_create: crs not found
#> proj_create: crs not found
#> class        : LAS (v1.2 format 1)
#> memory       : 253.4 Mb 
#> extent       : 761421.7, 762000, 3436500, 3438000 (xmin, xmax, ymin, ymax)
#> coord. ref.  : NA 
#> area         : 0.84 kunits²
#> points       : 3.32 million points
#> density      : 3.97 points/units²

But the LAS file is not 1.4 (1.2) and the use of rlas 1.4 and lidR 3.2 from github don't help. The laz file can be found here

1
  • Helps to add the R tag - some of us search for it and we'd miss this otherwise. – Spacedman Mar 6 at 15:41
4

Neither LAStools nor lidR understand the CRS properly. But lasinfo displays more information read in the header.

lidR uses the key 3072 in the GeoTiff Projection Keys which is exected to be the epsg code. In your case it contains 32767 which is not a valid epsg code.

sp::CRS(SRS_string = "ESPG:32767")
#> Error in sp::CRS(SRS_string = "ESPG:32767") : NA

In your case the header contains much more than the EPSG code so maybe there is something you can use to build a valid CRS. But there is nothing that can be parsed automatically in R (as far as I know) except the epsg code.

library(lidR)
readLASheader("USGS_LPC_MS_Tupelo_UTM15_2015_15RYQ605365_LAS_2016.laz")
#> File signature:           LASF 
#> File source ID:           0 
#> Global encoding:
#>  - GPS Time Type: Standard GPS Time 
#>  - Synthetic Return Numbers: no 
#>  - Well Know Text: CRS is GeoTIFF 
#>  - Aggregate Model: false 
#> Project ID - GUID:        1388176b-ba63-483e-1485-144d0f79a00a 
#> Version:                  1.2
#> System identifier:        Woolpert ALS70 Merged 
#> Generating software:      GeoCue LAS Updater 
#> File creation d/y:        326/2015
#> header size:              227 
#> Offset to point data:     897 
#> Num. var. length record:  3 
#> Point data format:        1 
#> Point data record length: 28 
#> Num. of point records:    3320964 
#> Num. of points by return: 2040179 984218 261869 32880 1789 
#> Scale factor X Y Z:       0.01 0.01 0.01 
#> Offset X Y Z:             0 0 0 
#> min X Y Z:                761421.7 3436500 86.85 
#> max X Y Z:                762000 3438000 141.06 
#> Variable Length Records (VLR):
#>    Variable Length Record 1 of 3 
#>        Description: GeoTiff Projection Keys 
#>        Tags:
#>           Key 1024 value 1 
#>           Key 1026 value 59 
#>           Key 2048 value 32767 
#>           Key 2049 value 124 
#>           Key 2050 value 32767 
#>           Key 2051 value 8901 
#>           Key 2054 value 9102 
#>           Key 2055 value 9 
#>           Key 2056 value 7019 
#>           Key 2057 value 6 
#>           Key 2059 value 7 
#>           Key 2061 value 8 
#>           Key 3072 value 32767 
#>           Key 3073 value 0 
#>           Key 3074 value 32767 
#>           Key 3075 value 1 
#>           Key 3076 value 9001 
#>           Key 3077 value 5 
#>           Key 3081 value 0 
#>           Key 3082 value 1 
#>           Key 3083 value 2 
#>           Key 3088 value 3 
#>           Key 3092 value 4 
#>           Key 4097 value 97 
#>           Key 4099 value 9001 
#>    Variable Length Record 2 of 3 
#>        Description: GeoTiff double parameters 
#>        data: 0 5e+05 0 -93 0.9996 1 6378137 298.2572 0 0.01745329 
#>    Variable Length Record 3 of 3 
#>        Description: GeoTiff ASCII parameters 
#>        data: NAD_1983_2011_UTM_Zone_15N|projection: Transverse Mercator|PCS Name = NAD_1983_2011_UTM_Zone_15N|NAVD88 - Geoid12A (Meters)|GCS Name = GCS_NAD_1983_2011|Datum = NAD_1983_2011|Ellipsoid = GRS_1980|Primem = Greenwich| 
#> Extended Variable Length Records (EVLR):  void

Created on 2021-03-06 by the reprex package (v1.0.0)

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