Changes between Version 30 and Version 31 of Processing/Lidarqcprocedure

Timestamp:

Sep 21, 2009, 11:51:56 AM (15 years ago)

Author:

emca

Comment:

--

Processing/Lidarqcprocedure

@@ -12 +12 @@
 '''Using Macros'''
 
-The first stage of the QC is to check the data and reclassify erroneous points. This can be done in Microstation/TerraSolid by creating a macro. It should be straightforward to script this into a GIS such as GRASS too.
+The first stage of the QC is to check the data and reclassify erroneous points to class 7 (low points). This can be done in Microstation/TerraSolid by creating a macro. It should be straightforward to script this into a GIS such as GRASS too.
 
 Start Microstation and goto Utilities -> MDL Applications -> Terrascan[[BR]]
@@ -24 +24 @@
  * Classify isolated points (Action: Classify Points, Routine: isolated points)
 
-To run on large projects use "selected files" instead of reading all LAS files into memory. 
+To run on large projects use "selected files" instead of reading all LAS files into memory. Ensure that the output format under 'Save As:' is .LAS 1.0.
 
-Ensure that the output format under 'Save As:' is .LAS 1.0.
 
-Check the result to see what points have been selected. 
 
 To remove haze layers, use elevation to threshold (Routine: by absolute elevation). Select an elevation range whose minimum is well above any ground targets and maximum above the haze layer.
@@ -38 +36 @@
 '''Note: Manually reclassifying points can only be done on a per flight line basis.'''
 
-Can use the Assign tool from the Classify menu to amend points which were missed or wrongly classified by the classification algorithms. Select the required options on the 'from' and 'to class'  drop down boxes and individually select a point to reclassify it. 
+Check the result to see what points have been classified using the macro. There may be points which were missed or wrongly classified by the classification algorithms.
+
+Can use the Assign tool from the Classify menu reclassify individual points. Select the required options on the 'from' and 'to class' drop down boxes and individually select a point to reclassify it. 
 
 If there are a large number of points to be reclassified manually there are several tools (available by clicking on the 'Create Editable Model' icon) which allow groups of points to be reclassified. Be careful if using the 'Classify Using Brush' tool. This tool becomes active once the left mouse button has been clicked and reclassified anything that falls with the region indicated by the mouse icon. Right click with the mouse to deactivate this tool.