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\\$2 \(la\\$1\(ra\\$3
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.if \n(.g .mso www.tmac
.TH las2txt 1 "27 October 2016" "" ""
.SH NAME
las2txt \- output ASRPS LAS files into ASCII text
.SH SYNOPSIS
'nh
.fi
.ad l
\fBlas2txt\fR \kx
.if (\nx>(\n(.l/2)) .nr x (\n(.l/5)
'in \n(.iu+\nxu
[\fB-h\fR | 
\fB-i\fR \fI<infile>\fR 
\fB-o\fR \fI<outfile>\fR 
\fB-t\fR \fI<format>\fR 
| \fB-formats\fR]
'in \n(.iu-\nxu
.ad b
'hy
.SH DESCRIPTION
\fBlas2txt\fR allows you to output ASRPS LAS files into
ASCII text.
.PP
The '\*(T<\fB\-parse txyz\fR\*(T>' flag specifies how to format each line
of the ASCII file.
For example, '\*(T<txyzia\*(T>' 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.
.PP
Supported entries
.TP 0.2i
\(bu
a - scan angle
.TP 0.2i
\(bu
i - intensity
.TP 0.2i
\(bu
n - number of returns for given pulse
.TP 0.2i
\(bu
r - number of this return
.TP 0.2i
\(bu
c - classification
.TP 0.2i
\(bu
u - user data
.TP 0.2i
\(bu
p - point source ID
.TP 0.2i
\(bu
e - edge of flight line flag
.TP 0.2i
\(bu
d - direction of scan flag 
.TP 0.2i
\(bu
R - red channel of RGB color
.TP 0.2i
\(bu
G - green channel of RGB color
.TP 0.2i
\(bu
B - blue channel of RGB color
.TP 0.2i
\(bu
M - vertex index number
.PP
Separators
.PP
The '\*(T<\fB\-sep space\fR\*(T>' flag specifies what separator to use.
The default is a space.
The following list is valid for separator characters (case sensitive):
.TP 0.2i
\(bu
tab
.TP 0.2i
\(bu
comma
.TP 0.2i
\(bu
colon
.TP 0.2i
\(bu
hyphen
.TP 0.2i
\(bu
dot
.TP 0.2i
\(bu
semicolon
.PP
Header Separators
.PP
The '\*(T<\fB\-header pound\fR\*(T>' 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):
.TP 0.2i
\(bu
percent
.TP 0.2i
\(bu
dollar
.TP 0.2i
\(bu
semicolon
.TP 0.2i
\(bu
comma
.TP 0.2i
\(bu
star
.TP 0.2i
\(bu
colon
.TP 0.2i
\(bu
semicolon
.SH OPTIONS
las2txt options:
.TP 
\*(T<\fB\-h\fR\*(T>, \*(T<\fB\-\-help\fR\*(T>
produce help message
.TP 
\*(T<\fB\-i\fR\*(T> \fIarg\fR, \*(T<\fB\-\-input\fR\*(T> \fIarg\fR
input LAS file.
.TP 
\*(T<\fB\-o\fR\*(T> \fIarg\fR, \*(T<\fB\-\-output\fR\*(T> \fIarg\fR
output text file.
Use 'stdout' if you want it written to the standard output stream
.TP 
\*(T<\fB\-\-parse\fR\*(T> \fIarg\fR
The '\*(T<\fB\-\-parse txyz\fR\*(T>' flag specifies how to format
each line of the ASCII file.

For example, '\*(T<txyzia\*(T>' 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:
.RS 
.TP 0.2i
\(bu
x - x coordinate as a double
.TP 0.2i
\(bu
y - y coordinate as a double
.TP 0.2i
\(bu
z - z coordinate as a double
.TP 0.2i
\(bu
X - x coordinate as unscaled integer
.TP 0.2i
\(bu
Y - y coordinate as unscaled integer
.TP 0.2i
\(bu
Z - z coordinate as unscaled integer
.TP 0.2i
\(bu
a - scan angle
.TP 0.2i
\(bu
i - intensity
.TP 0.2i
\(bu
n - number of returns for given pulse
.TP 0.2i
\(bu
r - number of this return
.TP 0.2i
\(bu
c - classification number
.TP 0.2i
\(bu
C - classification name
.TP 0.2i
\(bu
u - user data
.TP 0.2i
\(bu
p - point source ID
.TP 0.2i
\(bu
e - edge of flight line
.TP 0.2i
\(bu
d - direction of scan flag
.TP 0.2i
\(bu
R - red channel of RGB color
.TP 0.2i
\(bu
G - green channel of RGB color
.TP 0.2i
\(bu
B - blue channel of RGB color
.TP 0.2i
\(bu
M - vertex index number
.RE
.TP 
\*(T<\fB\-\-precision\fR\*(T> \fIarg\fR
The number of decimal places to use for x,y,z,[t] output. 
\*(T<\fB\-\-precision 7 7 3\fR\*(T>
\*(T<\fB\-\-precision 3 3 4 6\fR\*(T>
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.)
.TP 
\*(T<\fB\-\-delimiter\fR\*(T> \fIarg\fR
The character to use for delimiting fields in the output.
\*(T<\fB\-\-delimiter ","\fR\*(T>
\*(T<\fB\-\-delimiter ""\fR\*(T>
\*(T<\fB\-\-delimiter " "\fR\*(T>
.TP 
\*(T<\fB\-\-labels\fR\*(T>
Print row of header labels
.TP 
\*(T<\fB\-\-header\fR\*(T>
Print header information
.TP 
\*(T<\fB\-v\fR\*(T>, \*(T<\fB\-\-verbose\fR\*(T>
Verbose message output
.TP 
\*(T<\fB\-\-xml\fR\*(T>
Output as XML.
No formatting given by \*(T<\fB\-\-parse\fR\*(T>
is respected in this case.
.TP 
\*(T<\fB\-\-stdout\fR\*(T>
Output data to stdout
.PP
Filtering options:
.TP 
\*(T<\fB\-e\fR\*(T> \fIarg\fR, \*(T<\fB\-\-extent\fR\*(T> \fIarg\fR
Extent window that points must fall within to keep.
Use a comma-separated or quoted, space-separated list,
for example, 
\*(T<\fB\-e minx, miny, maxx, maxy\fR\*(T>
or 
\*(T<\fB\-e minx, miny, minz, maxx, maxy, maxz\fR\*(T>
\*(T<\fB\-e "minx miny minz maxx maxy maxz"\fR\*(T>
.TP 
\*(T<\fB\-\-minx\fR\*(T> \fIarg\fR
Extent must be greater than or equal to minx to be kept. 
\*(T<\fB\-\-minx 1234.0\fR\*(T>
.TP 
\*(T<\fB\-\-miny\fR\*(T> \fIarg\fR
Extent must be greater than or equal to miny to be kept. 
\*(T<\fB\-\-miny 5678.0\fR\*(T>
.TP 
\*(T<\fB\-\-minz\fR\*(T> \fIarg\fR
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.
\*(T<\fB\-\-minz 0.0\fR\*(T>
.TP 
\*(T<\fB\-\-maxx\fR\*(T> \fIarg\fR
Extent must be less than or equal to maxx to be kept. 
\*(T<\fB\-\-maxx 1234.0\fR\*(T>
.TP 
\*(T<\fB\-\-maxy\fR\*(T> \fIarg\fR
Extent must be less than or equal to maxy to be kept. 
\*(T<\fB\-\-maxy 5678.0\fR\*(T>
.TP 
\*(T<\fB\-\-maxz\fR\*(T> \fIarg\fR
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. 
\*(T<\fB\-\-maxz 10.0\fR\*(T>
.TP 
\*(T<\fB\-t\fR\*(T> \fIarg\fR, \*(T<\fB\-\-thin\fR\*(T> \fIarg\fR (=0)
Simple decimation-style thinning.
Thin the file by removing every t'th point from the file.
.TP 
\*(T<\fB\-\-last\-return\-only\fR\*(T>
Keep last returns
(cannot be used with \*(T<\fB\-\-first\-return\-only\fR\*(T>)
.TP 
\*(T<\fB\-\-first\-return\-only\fR\*(T>
Keep first returns
(cannot be used with \*(T<\fB\-\-last\-return\-only\fR\*(T>)
.TP 
\*(T<\fB\-\-keep\-returns\fR\*(T> \fIarg\fR
A list of return numbers to keep in the output file: 
\*(T<\fB\-\-keep\-returns 1 2 3\fR\*(T>
.TP 
\*(T<\fB\-\-drop\-returns\fR\*(T> \fIarg\fR
Return numbers to drop.
For example, \*(T<\fB\-\-drop\-returns 2 3 4 5\fR\*(T>
.TP 
\*(T<\fB\-\-valid_only\fR\*(T>
Keep only valid points
.TP 
\*(T<\fB\-\-keep\-classes\fR\*(T> \fIarg\fR
A list of classifications to keep:
\*(T<\fB\-\-keep\-classes 2 4 12\fR\*(T>
\*(T<\fB\-\-keep\-classes 2\fR\*(T>
.TP 
\*(T<\fB\-\-drop\-classes\fR\*(T> \fIarg\fR
A comma-separated list of classifications to drop:
\*(T<\fB\-\-drop\-classes 1,7,8\fR\*(T>
\*(T<\fB\-\-drop\-classes 2\fR\*(T>
.TP 
\*(T<\fB\-\-keep\-intensity\fR\*(T> \fIarg\fR
Range in which to keep intensity.
The following expression types are supported: 
\*(T<\fB\-\-keep\-intensity 0\-100\fR\*(T>
\*(T<\fB\-\-keep\-intensity <200\fR\*(T>
\*(T<\fB\-\-keep\-intensity >400\fR\*(T>
\*(T<\fB\-\-keep\-intensity >=200\fR\*(T>
.TP 
\*(T<\fB\-\-drop\-intensity\fR\*(T> \fIarg\fR
Range in which to drop intensity.
The following expression types are supported: 
\*(T<\fB\-\-drop\-intensity <200\fR\*(T>
\*(T<\fB\-\-drop\-intensity >400\fR\*(T>
\*(T<\fB\-\-drop\-intensity >=200\fR\*(T>
.TP 
\*(T<\fB\-\-keep\-time\fR\*(T> \fIarg\fR
Range in which to keep time.
The following expression types are supported: 
\*(T<\fB\-\-keep\-time 413665.2336\-414092.8462\fR\*(T>
\*(T<\fB\-\-keep\-time <414094.8462\fR\*(T>
\*(T<\fB\-\-keep\-time >413665.2336\fR\*(T>
\*(T<\fB\-\-keep\-time >=413665.2336\fR\*(T>
.TP 
\*(T<\fB\-\-drop\-time\fR\*(T> \fIarg\fR
Range in which to drop time.
The following expression types are supported: 
\*(T<\fB\-\-drop\-time <413666.2336\fR\*(T>
\*(T<\fB\-\-drop\-time >413665.2336\fR\*(T>
\*(T<\fB\-\-drop\-time >=413665.2336\fR\*(T>
.TP 
\*(T<\fB\-\-keep\-scan\-angle\fR\*(T> \fIarg\fR
Range in which to keep scan angle.
The following expression types are supported: 
\*(T<\fB\-\-keep\-scan\-angle 0\-100\fR\*(T>
\*(T<\fB\-\-keep\-scan\-angle <100\fR\*(T>
\*(T<\fB\-\-keep\-scan\-angle <=100\fR\*(T>
.TP 
\*(T<\fB\-\-drop\-scan\-angle\fR\*(T> \fIarg\fR
Range in which to drop scan angle.
The following expression types are supported: 
\*(T<\fB\-\-drop\-scan\-angle <30\fR\*(T>
\*(T<\fB\-\-drop\-scan\-angle >100\fR\*(T>
\*(T<\fB\-\-drop\-scan\-angle >=100\fR\*(T>
.TP 
\*(T<\fB\-\-keep\-color\fR\*(T> \fIarg\fR
Range in which to keep colors.
Define colors as two 3-tuples (R,G,B-R,G,B): 
\*(T<\fB\-\-keep\-color '0,0,0\-125,125,125'\fR\*(T>
.TP 
\*(T<\fB\-\-drop\-color\fR\*(T> \fIarg\fR
Range in which to drop colors.
Define colors as two 3-tuples (R,G,B-R,G,B): 
\*(T<\fB\-\-drop\-color '255,255,255\-65536,65536,65536'\fR\*(T>
.PP
For more information, see the full documentation for lasinfo at:
\(lahttp://liblas.org/utilities/las2txt.html\(ra
.SH EXAMPLE
\fBSimple conversion to text file\fR
.PP
.nf
\*(T<
$ las2txt \-i lidar.las \-o lidar.txt \-parse xyz
      \*(T>
.fi

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.

\fBSpecifying a separator\fR
.PP
.nf
\*(T<
$ las2txt \-i lidar.las \-o lidar.txt \-parse txyzr \-sep komma
      \*(T>
.fi

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.

\fBAltering the header separator\fR
.PP
.nf
\*(T<
$ las2txt \-i lidar.las \-o lidar.txt \-parse xyzia \-sep semicolon \-header pound
      \*(T>
.fi

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.

\fBAltering the coordinate order\fR
.PP
.nf
\*(T<
$ las2txt \-i lidar.las \-o lidar.txt \-parse xyzcu \-sep tab \-header percent
      \*(T>
.fi

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.