1::
2:: a batch script for generating a pit-free CHM as outlined
3:: in the Silvilaser 2013 poster by A. Khosravipour et al.
4::
5
6::
7:: specify parameters
8::
9
10:: allows you to run the script from other folders
11set PATH=%PATH%;D:\lastools\bin;
12
13:: here we specify the input (already height-normalized)
14set NORMALIZED_LIDAR=D:\data\normalized\bois_noir.laz
15
16:: specify the desired resolution
17set STEP=0.5
18
19:: specify the desired triangle kill (about 3 times the step)
20set KILL=1.5
21
22:: specify a temporary directory for the partial CHMs
23set TEMP_CHM_DIR=temp_chms
24
25:: specify the final output CHM file name and format
26set PIT_FREE_CHM=D:\data\result\chm.tif
27
28rmdir %TEMP_CHM_DIR% /s /q
29mkdir %TEMP_CHM_DIR%
30
31::
32:: do the actual processing
33::
34
35blast2dem -i %NORMALIZED_LIDAR% ^
36          -keep_first ^
37          -step %STEP% ^
38          -odir %TEMP_CHM_DIR% -odix _00 -obil
39
40blast2dem -i %NORMALIZED_LIDAR% ^
41          -keep_first -drop_z_below 2 ^
42          -step %STEP% -kill %KILL% ^
43          -odir %TEMP_CHM_DIR% -odix _02 -obil
44
45blast2dem -i %NORMALIZED_LIDAR% ^
46          -keep_first -drop_z_below 5 ^
47          -step %STEP% -kill %KILL% ^
48          -odir %TEMP_CHM_DIR% -odix _05 -obil
49
50blast2dem -i %NORMALIZED_LIDAR% ^
51          -keep_first -drop_z_below 10 ^
52          -step %STEP% -kill %KILL% ^
53          -odir %TEMP_CHM_DIR% -odix _10 -obil
54
55blast2dem -i %NORMALIZED_LIDAR% ^
56          -keep_first -drop_z_below 15 ^
57          -step %STEP% -kill %KILL% ^
58          -odir %TEMP_CHM_DIR% -odix _15 -obil
59
60:: this would be sufficient for forests with tree height
61:: of up to about 20 meter. maybe delete higher up steps
62
63blast2dem -i %NORMALIZED_LIDAR% ^
64          -keep_first -drop_z_below 20 ^
65          -step %STEP% -kill %KILL% ^
66          -odir %TEMP_CHM_DIR% -odix _20 -obil
67
68blast2dem -i %NORMALIZED_LIDAR% ^
69          -keep_first -drop_z_below 25 ^
70          -step %STEP% -kill %KILL% ^
71          -odir %TEMP_CHM_DIR% -odix _25 -obil
72
73blast2dem -i %NORMALIZED_LIDAR% ^
74          -keep_first -drop_z_below 30 ^
75          -step %STEP% -kill %KILL% ^
76          -odir %TEMP_CHM_DIR% -odix _30 -obil
77
78:: merge partial CHMs together into pit-free CHM
79
80lasgrid -i %TEMP_CHM_DIR%\*.bil -merged ^
81        -step %STEP% -highest ^
82        -o %PIT_FREE_CHM%
83
84:: remove the temporary files and directory
85
86rmdir %TEMP_CHM_DIR% /s /q
87
88echo "bye bye"
89