NAME
las2txt - output ASRPS LAS files into ASCII text
SYNOPSIS
las2txt [-h | -i <infile> -o <outfile> -t <format> | -formats]
DESCRIPTION
las2txt allows you to output ASRPS LAS files into ASCII text.
The 'FC-parse txyzF[0]' flag specifies how to format each line of the ASCII file. For example, 'FCtxyziaF[0]' means that the first number of each line should be the gpstime, the next three numbers should be the x, y, and z coordinate, the next number should be the intensity and the next number should be the scan angle.
Supported entries
- •
-
a - scan angle
- •
-
i - intensity
- •
-
n - number of returns for given pulse
- •
-
r - number of this return
- •
-
c - classification
- •
-
u - user data
- •
-
p - point source ID
- •
-
e - edge of flight line flag
- •
-
d - direction of scan flag
- •
-
R - red channel of RGB color
- •
-
G - green channel of RGB color
- •
-
B - blue channel of RGB color
- •
-
M - vertex index number
Separators
The 'FC-sep spaceF[0]' flag specifies what separator to use. The default is a space. The following list is valid for separator characters (case sensitive):
- •
-
tab
- •
-
comma
- •
-
colon
- •
-
hyphen
- •
-
dot
- •
-
semicolon
Header Separators
The 'FC-header poundF[0]' flag results in the header information being printed at the beginning of the ASCII file in form of a comment that starts with the special character '#'. Other possible special characters include (case sensitive):
- •
-
percent
- •
-
dollar
- •
-
semicolon
- •
-
comma
- •
-
star
- •
-
colon
- •
-
semicolon
OPTIONS
las2txt options:
- FC-hF[0], FC--helpF[0]
-
produce help message
- FC-iF[0] arg, FC--inputF[0] arg
-
input LAS file.
- FC-oF[0] arg, FC--outputF[0] arg
-
output text file. Use 'stdout' if you want it written to the standard output stream
- FC--parseF[0] arg
-
The 'FC--parse txyzF[0]' flag specifies how to format each line of the ASCII file.
For example, 'FCtxyziaF[0]' means that the first number of each line should be the gpstime, the next three numbers should be the x, y, and z coordinate, the next number should be the intensity and the next number should be the scan angle.
The supported entries are:
- •
-
x - x coordinate as a double
- •
-
y - y coordinate as a double
- •
-
z - z coordinate as a double
- •
-
X - x coordinate as unscaled integer
- •
-
Y - y coordinate as unscaled integer
- •
-
Z - z coordinate as unscaled integer
- •
-
a - scan angle
- •
-
i - intensity
- •
-
n - number of returns for given pulse
- •
-
r - number of this return
- •
-
c - classification number
- •
-
C - classification name
- •
-
u - user data
- •
-
p - point source ID
- •
-
e - edge of flight line
- •
-
d - direction of scan flag
- •
-
R - red channel of RGB color
- •
-
G - green channel of RGB color
- •
-
B - blue channel of RGB color
- •
-
M - vertex index number
- FC--precisionF[0] arg
-
The number of decimal places to use for x,y,z,[t] output. FC--precision 7 7 3F[0] FC--precision 3 3 4 6F[0] If you don't specify any precision, las2txt uses the implicit values defined by the header's scale value (and a precision of 8 is used for any time values.)
- FC--delimiterF[0] arg
-
The character to use for delimiting fields in the output. FC--delimiter ","F[0] FC--delimiter ""F[0] FC--delimiter " "F[0]
- FC--labelsF[0]
-
Print row of header labels
- FC--headerF[0]
-
Print header information
- FC-vF[0], FC--verboseF[0]
-
Verbose message output
- FC--xmlF[0]
-
Output as XML. No formatting given by FC--parseF[0] is respected in this case.
- FC--stdoutF[0]
-
Output data to stdout
Filtering options:
- FC-eF[0] arg, FC--extentF[0] arg
-
Extent window that points must fall within to keep. Use a comma-separated or quoted, space-separated list, for example, FC-e minx, miny, maxx, maxyF[0] or FC-e minx, miny, minz, maxx, maxy, maxzF[0] FC-e "minx miny minz maxx maxy maxz"F[0]
- FC--minxF[0] arg
-
Extent must be greater than or equal to minx to be kept. FC--minx 1234.0F[0]
- FC--minyF[0] arg
-
Extent must be greater than or equal to miny to be kept. FC--miny 5678.0F[0]
- FC--minzF[0] arg
-
Extent must be greater than or equal to minz to be kept. If maxx and maxy are set but not minz *and maxz, all z values are kept. FC--minz 0.0F[0]
- FC--maxxF[0] arg
-
Extent must be less than or equal to maxx to be kept. FC--maxx 1234.0F[0]
- FC--maxyF[0] arg
-
Extent must be less than or equal to maxy to be kept. FC--maxy 5678.0F[0]
- FC--maxzF[0] arg
-
Extent must be less than or equal to maxz to be kept. If maxx and maxy are set but not maxz *and minz, all z values are kept. FC--maxz 10.0F[0]
- FC-tF[0] arg, FC--thinF[0] arg (=0)
-
Simple decimation-style thinning. Thin the file by removing every t'th point from the file.
- FC--last-return-onlyF[0]
-
Keep last returns (cannot be used with FC--first-return-onlyF[0])
- FC--first-return-onlyF[0]
-
Keep first returns (cannot be used with FC--last-return-onlyF[0])
- FC--keep-returnsF[0] arg
-
A list of return numbers to keep in the output file: FC--keep-returns 1 2 3F[0]
- FC--drop-returnsF[0] arg
-
Return numbers to drop. For example, FC--drop-returns 2 3 4 5F[0]
- FC--valid_onlyF[0]
-
Keep only valid points
- FC--keep-classesF[0] arg
-
A list of classifications to keep: FC--keep-classes 2 4 12F[0] FC--keep-classes 2F[0]
- FC--drop-classesF[0] arg
-
A comma-separated list of classifications to drop: FC--drop-classes 1,7,8F[0] FC--drop-classes 2F[0]
- FC--keep-intensityF[0] arg
-
Range in which to keep intensity. The following expression types are supported: FC--keep-intensity 0-100F[0] FC--keep-intensity <200F[0] FC--keep-intensity >400F[0] FC--keep-intensity >=200F[0]
- FC--drop-intensityF[0] arg
-
Range in which to drop intensity. The following expression types are supported: FC--drop-intensity <200F[0] FC--drop-intensity >400F[0] FC--drop-intensity >=200F[0]
- FC--keep-timeF[0] arg
-
Range in which to keep time. The following expression types are supported: FC--keep-time 413665.2336-414092.8462F[0] FC--keep-time <414094.8462F[0] FC--keep-time >413665.2336F[0] FC--keep-time >=413665.2336F[0]
- FC--drop-timeF[0] arg
-
Range in which to drop time. The following expression types are supported: FC--drop-time <413666.2336F[0] FC--drop-time >413665.2336F[0] FC--drop-time >=413665.2336F[0]
- FC--keep-scan-angleF[0] arg
-
Range in which to keep scan angle. The following expression types are supported: FC--keep-scan-angle 0-100F[0] FC--keep-scan-angle <100F[0] FC--keep-scan-angle <=100F[0]
- FC--drop-scan-angleF[0] arg
-
Range in which to drop scan angle. The following expression types are supported: FC--drop-scan-angle <30F[0] FC--drop-scan-angle >100F[0] FC--drop-scan-angle >=100F[0]
- FC--keep-colorF[0] arg
-
Range in which to keep colors. Define colors as two 3-tuples (R,G,B-R,G,B): FC--keep-color '0,0,0-125,125,125'F[0]
- FC--drop-colorF[0] arg
-
Range in which to drop colors. Define colors as two 3-tuples (R,G,B-R,G,B): FC--drop-color '255,255,255-65536,65536,65536'F[0]
For more information, see the full documentation for lasinfo at: ⟨http://liblas.org/utilities/las2txt.html⟩
EXAMPLE
Simple conversion to text file
FC
$ las2txt -i lidar.las -o lidar.txt -parse xyz
F[0]
converts LAS file to ASCII and places the x, y, and z coordinate of each point at the 1st, 2nd, and 3rd entry of each line. The entries are separated by a space.
Specifying a separator
FC
$ las2txt -i lidar.las -o lidar.txt -parse txyzr -sep komma
F[0]
converts LAS file to ASCII and places the gps_time as the first entry, the x, y, and z coordinates at the 2nd, 3rd, and 4th entry and the number of the return as the 5th entry of each line. The entries are separated by a komma.
Altering the header separator
FC
$ las2txt -i lidar.las -o lidar.txt -parse xyzia -sep semicolon -header pound
F[0]
converts LAS file to ASCII and places the x, y, and z coordinate at the 1st, 2nd, and 3rd entry, the intensity at the 4th and the scan angle as the 5th entry of each line. The entries are separated by a semicolon. At the beginning of the file we print the header information as a comment starting with a '#' symbol.
Altering the coordinate order
FC
$ las2txt -i lidar.las -o lidar.txt -parse xyzcu -sep tab -header percent
F[0]
converts LAS file to ASCII and places the x, y, and z coordinate at the 1st, 2nd, and 3rd entry, the classification at the 4th and the user data as the 5th entry of each line. The entries are separated by a semicolon. At the beginning of the file we print the header information as a comment starting with a '%' symbol.