The Square up Buildings dialog includes squaring up options for matching the polygon to the underlying building shape, using straight sides.
Access Location:
LIDAR Analyst
Menu (LIDAR Analyst Toolbar): LIDAR Analyst > Enhancement > Square Up Buildings
Toolbar: LIDAR Analyst Building Edit
Command: Square Up Building
Doc Id: 10302
Figure 94: Square Up Buildings
Square up Buildings Options
Bare earth
Allows you to choose the bare earth file.
Single/last return
Displays the selected single/last return image.
First return
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Horizontal units
Allows you to choose the horizontal units for squaring up buildings including Unknown, Inches, Feet, Miles, Centimeters, Meters, Kilometers, Decimal Degrees, Minutes, Seconds, and Radians.
Vertical units
Allows you to choose the vertical units for squaring up buildings including Unknown, Inches, Feet, Miles, Centimeters, Meters, and Kilometers.
Real-Time Preview
Fills selected polygons with specified color or adds vertices to selected lines.
Smoothing Tolerance
Enter the number of meters a building vertex is allowed to move to smooth the building edges. Tolerance defines the maximum distance a point can move in relation to its neighboring vertices. This function is the same as the one found in the Buildings Extraction window. Values entered in either one will be reflected in the other. Smoothing is accomplished with the Bezier Smoothing algorithm. The default is 1 meter.
Squaring Tolerance
Sets the number of meters that the vertices of an edge can move when snapping the edge vertical or horizontal. The default is 6 meters.
Consider all likely feature orientations when squaring up
Attempts many likely orientations and squares up features using the orientation that provides the best results. Selected by default.
Fine-tune rotation
Fine-tunes the orientation angle of the polygon by the specified number of degrees. The default value is 0 degrees.
Consider adjoining features when computing orientation
Takes into account the orientation of adjoining features when squaring each feature. Not selected by default.
Z-enable buildings using
Allows you to choose the z-value setting including No z-value, Actual z-value, Min. z-value, Max. z-value, and Mean z-value.
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Tree Extraction Dialog
The Tree Extraction dialog is used to specify tree and forest extraction settings. You can optimize results for dense forests or more accurate crown widths.
Access Location:
LIDAR Analyst
Toolbar: LIDAR Analyst
Menu (LIDAR Analyst Toolbar): LIDAR Analyst > Extraction
Command: Extract Trees
Doc Id: 10130
Figure 95: Tree Extraction
Tree Extraction Options
Bare earth
Displays the bare earth file for the building extraction.
Single/last return
Displays the single/last return field.
First return
Displays in the First Return field.
Buildings
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Horizontal units
Sets the horizontal units for the tree extraction including Unknown, Inches, Feet, Miles, Centimeters, Meters, Kilometers, Decimal Degrees, Minutes, Seconds, and Radians.
Vertical units
Sets the vertical units for the tree extraction including Unknown, Inches, Feet, Miles, Centimeters, Meters, and Kilometers.
Method 1: Fixed window search
Extraction method for the tree extraction process (better for dense forests).
Method 2: Variable window search
Extraction method for the tree extraction process (better at getting accurate crown widths).
Figure 96: Tree Extraction Process Diagram
Note: Forest parameters are not available unless you select the Forest option at the bottom of the
dialog and designate a file output
Predominant tree/forest type
Set the predominant tree/forest type to match the type of trees present in the data. If most of the trees are either deciduous or coniferous, then select the corresponding tree type option. Select ‘Mixed’ if the data contain a blend of deciduous and coniferous trees. Select ‘Deciduous’ or ‘Coniferous’ if the data is mostly one type of tree. Selecting the appropriate type increases the accuracy of the tree extraction and attribution. The default setting is "Mixed".
Minimum tree height
Enter the minimum tree height to extract. The minimum tree height determines the minimum height a potential tree point has to have in order to be classified as a tree. Set this value
appropriately for the data being processed. The minimum tree height is measured from the highest point of the tree crown to the ground (the length between A and C in the above diagram). The default is 3 meters.
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Maximum tree height
Enter the maximum tree height to extract. The maximum tree height determines the maximum height a potential tree point has to have in order to be classified as a tree. Set this value appropriately for the data being processed. The maximum tree height is measured from the highest point of the tree crown to the ground.
Typical tree height
Enter the average height of the tree to extract that is representative of the height of the trees you want to extract. Height is measured at the highest point of the tree crown, from (A) to (C) in the diagram above. It should be noted that setting the value too high will decrease the number of tree points extracted. The default is 40 meters.
Minimum size of a forest
Enter the minimum forest size that LIDAR Analyst should extract in a forest extraction. Available only when the Output forest areas option is selected. Determines how large of an area an extracted forest has to cover in order to be kept in the final output. The default is 600 square meters.
Tree points
Select Tree Points to return a point vector file showing individual trees. The default is selected.
Forest areas
Select to return a polygon vector file showing trees grouped together in forests or stands. When selected the Minimum size of a forest, becomes available. The default is selected.
Reset to defaults
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