Changeset 834 for trunk/doc/lasinfo.txt
- Timestamp:
- 08/17/08 03:01:31 (4 months ago)
- Files:
-
- 1 modified
-
trunk/doc/lasinfo.txt (modified) (7 diffs)
Legend:
- Unmodified
- Added
- Removed
-
trunk/doc/lasinfo.txt
r813 r834 1 1 **************************************************************** 2 lasinfo: converts from binary LAS to a standard ASCII format2 lasinfo: a utility for inspecting LAS files 3 3 **************************************************************** 4 4 5 5 :Author: Martin Isenburg 6 6 :Contact: isenburg@cs.unc.edu 7 :Author: Howard Butler 8 :Contact: hobu.inc@gmail.com 7 9 :Revision: $Revision$ 8 10 :Date: $Date$ … … 14 16 :backlinks: top 15 17 16 lasinfo prints the header contents and a short summary of the points. When 17 there are differences between header info and point content they are reported 18 as a warning. 18 Description 19 ----------- 19 20 20 lasinfo can also be used to modify entries in the header as described below. 21 `lasinfo` prints the header contents by default, and with a switch, can 22 be used to print a short summary of the points. When in summary mode (using 23 the --check switch), differences between header info and point content are 24 reported as warnings. `lasinfo` prints its information to stderr, and you 25 can use pipes to redirect the output of `lasinfo` as necessary. `lasinfo` 26 supports reading from stdin, but it does not attempt to read from stdin if the 27 --stdin switch is not used. `lasinfo` can also be used to modify a few header 28 entries in-place as described in the examples. 29 30 `lasinfo` is a port of Martin Isenburg's `lasinfo` utility from `LASTools`_ 31 to the libLAS library. For the most part, it is unchanged from Martin's 32 utility except for a few differences: 33 34 * It does *not* scan the points by default and instead you must use the --check 35 switch to have them scanned. 36 37 * It *does* print the Variable Length Records (VLRs) by default. 38 39 * Slightly different (and tidier) output format. 40 41 * GNU-style arguments and switches (although most of the switches used by 42 Martin's utilities should continue to work). 43 21 44 22 45 Usage 23 46 ----- 24 47 25 Simple info26 ~~~~~~~~~~~ 48 Simple header inspection 49 ~~~~~~~~~~~~~~~~~~~~~~~~ 27 50 28 51 :: … … 30 53 $ lasinfo lidar.las 31 54 $ lasinfo --input lidar.las 32 33 reports header information.34 55 35 56 … … 42 63 43 64 44 Report Variable Header 45 ~~~~~~~~~~~~~~~~~~~~~~ 65 Variable Header Records 66 ~~~~~~~~~~~~~~~~~~~~~~~ 46 67 47 68 :: 48 69 49 $ lasinfo --input lidar.las - variable70 $ lasinfo --input lidar.las -skip_vlr 50 71 51 also reports the contents of any variable headers there might be.72 will skip the printing of Variable Record Headers (VLRs) for the file. 52 73 53 Read through just the header 54 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 74 Check the points for header inconsistencies 75 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 55 76 56 77 :: 57 78 58 $ lasinfo --input lidar.las -- nocheck79 $ lasinfo --input lidar.las --check 59 80 60 omits reading over all the points. Only reports header information. 81 scans over all the points and reports any differences with the header. 82 Descriptive information like minimums and maximums of various variables 83 (time, x, y, z, etc) and some basic histograms are also reported. 61 84 62 Attempt to repair missing header entries 63 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 85 Repair missing or inconsistent header information 86 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 64 87 65 88 :: … … 67 90 $ lasinfo --input lidar.las --repair 68 91 69 if there are missing or wrong entries in the header they are corrected. 92 will add missing or repair inconsistent header entries with respect to the points. 93 Items that are repaired with --repair include the bounding box header entries 94 and the point records by return count. Future versions of the software may 95 include other header repair types if they can be done in such a way as to not 96 require rewriting of the file. 70 97 71 98 Update bounding box of LAS file … … 83 110 :: 84 111 85 $ lasinfo -i lidar.las - file_creation 8 2007112 $ lasinfo -i lidar.las --file_creation 8 2007 86 113 87 sets the file creation day/year in the header to 8/2007. 114 sets the file creation day/year in the header to 8/2007. With accordance to the 115 ASPRS LAS specification, this literally means the 8th day of 2007. 88 116 89 117 Set system identifier … … 118 146 http://www.appliedimagery.com/Serpent%20Mound%20Model%20LAS%20Data.las 119 147 148 .. _`LAStools`: http://www.cs.unc.edu/~isenburg/lastools/
