root/trunk/doc/las2txt.txt
| Revision 813, 3.2 kB (checked in by mloskot, 6 weeks ago) | |
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las2txt: converts from binary LAS to a standard ASCII format
| Author: | Martin Isenburg |
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| Contact: | isenburg@cs.unc.edu |
| Revision: | $Revision$ |
| Date: | $Date$ |
1 Simple conversion to text file
$ las2txt -i lidar.las -o lidar.txt -parse xyz
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 seperated by a space.
2 Specifying a separator
$ las2txt -i lidar.las -o lidar.txt -parse txyzr -sep komma
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.
3 Altering the header separtor
$ las2txt -i lidar.las -o lidar.txt -parse xyzia -sep semicolon -header pound
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.
4 Altering the coordinate order
$ las2txt -i lidar.las -o lidar.txt -parse xyzcu -sep tab -header percent
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.
5 Usage
C:\lastools\bin>las2txt -h usage: las2txt lidar.las las2txt -parse xyziar lidar.las lidar.txt las2txt -i lidar.las -o lidar.laz -parse xyz las2txt -parse xyzt -verbose lidar.las las2txt -parse xyz lidar.las.gz las2txt -h
The '-parse txyz' flag specifies how to format each each line of the ASCII file. For example, 'txyzia' 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.
5.1 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
5.2 Separators
The '-sep space' flag specifies what separator to use. The default is a space but 'tab', 'komma', 'colon', 'hyphen', 'dot', or 'semicolon' are other possibilities.
5.3 Header Separators
The '-header pound' 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 '#'. Also possible are 'percent', 'dollar', 'semicolon', 'komma', 'star', 'colon', or 'semicolon' as that special character.
