Power line detection
Menu: Analyze / Power line detection
The power line detection tool was developed to automatically detect and vectorize power lines. When first opening the tool, an empty list of power lines as well as a few options appear in the right hand portion of the window. There is also a toolbar to manage any detected power lines as well as saving options at the bottom of the window.
Main interface
Detected lines
First, you will need to set up the detection parameters. To do so, click on ''Detection'' and review the options available.
- Min. segm. length: This option determines the minimum segment length that will be detected. The smaller this value is, the more points will be detected per power line.
- Max. segm. length: This option determines the maximum segment length that will be detected. The larger this value is, the less points will be detected per power line.
- Max. Z distance: This option determines the maximum distance in elevation (Z) that will be tolerated. Sometimes when power lines are not being fully detected, it can be helpful to slightly increase this value. However, if the maximum Z distance is too high, the algorithm may confuse neighboring power lines as being the same.
- Max. XY distance: This option determines the maximum distance in planimetry (X and Y) that will be tolerated. Sometimes when power lines are not being fully detected, it can be helpful to slightly increase this value. However, if the maximum X and Y distance is too high, the algorithm may confuse neighboring power lines as being the same.
- Search radius: This value determines the search radius for detecting other power lines. The search radius will be used only if the option Single line is unchecked, meaning that multiple lines will be detected at once.
- Min. dist. betw. lines: This value determines the minimal distance between two detected lines. This option was added to avoid detecting too many lines in a given area.
To vectorize your powerlines, you will have the option between ''Detect from class'' and ''Detect from points''.
In ''Detect from class'', the software will automatically vectorize all the lines and poles within the point cloud using the classification previously done. Simply select the corresponding class for each element then click 
to begin the process.
In ''Detect from points'', the user will have to manually click the starting point for the detection on a line by clicking 
. Then click to begin the process. If ''Single line'' is checked, only one line will be detected at a time, otherwise the software will detect all the lines around the starting point within the ''Search radius'' specified in ''Detection''.
The power line detection tool has a few options to manage any power line in the item list:
| Icon | Description |
|---|---|
| Deletes all selected objects in the item list |
| Invites the user to click on an existing power line to be identified on screen; the power line in question will be highlighted in the list |
| Split a line. The user must click on the power line to split on the screen. The original line will be kept and the newly split portion of the line will be added to the end of the item list. |
| Merges two lines together. The user must click on two power lines on the screen. The function will merge the extremities of each line that was clicked; if the furthest extremity was clicked, this will be the end that will be merged. The merged line will be added to the list. The two previous lines will not be deleted. |
There are also a few options at the bottom of the window:
- Save: Saves the selected power lines to a PWL or TXT format.
- Load: Loads a PWL or TXT file to the item list while clearing existing items.
- Add: Adds a PWL or TXT file to the item list. Does not clear existing items.
- Export: Exports selected power lines to DXF or shapefile format.
Once items have been added to the list, it will be possible to modify them. Power lines may be selected or deselected, this will show them or not. Power lines may be renamed and their colors may be changed. Right clicking on a specific power line shows a contextual menu:
- Check all: Selects all power lines in the list; displaying all items on the screen.
- Uncheck all: Deselects all power lines in the list; hiding items on the screen.
- Delete current: Deletes the currently selected power line.
- Split: Activates the split function. The line to be split does not necessarily have to be the selected line.
- Merge: Activates the merge fucntion. The lines to be merged can be any lines displayed on the screen.
It is also possible to expand a power line to view the points contained in the line. Click on Points to expand a power line and view the list. By right clicking on a point in the list, a contextual menu will display a few extra options.
- Hide points: Collapses the current power line, hiding the list of points.
- Remove all: Empties the points in the list. The power line will contain 0 points.
- Remove current: Removes the current point from the list.
- Insert: Adds a point before the current point and updates the point list.
- Repick: Allows the user to repick the selected point. The selected point should be highlighted in red on the screen.
Add manually
In this section it is possible to manually add a power line. This option can be used for hard-to-detect power lines or for lines that require a specific vectorization.
- Add a line: This button will add an empty line to the list of power lines on the left of the window.
- Start/Stop pick: After clicking on Add a line, the Start pick mode is automatically activated. This will set the tool to picking mode – where the user may manually vectorize a power line by clicking on points in the main screen. Once picking the line is complete, click on Stop pick to exit picking mode.
It is also possible to add points to an existing line. Simply select the line in the list and click on Start pick. Pick as many points as necessary and click on Stop pick to exit picking mode.
Classify
The classification tool is used to classify power lines detected using ''Detect from points'' to a specific class.
- Class: A class number must be entered here. For example, if the number 15 is entered, all points within the given radius will be marked as belonging to class 15. The user may also rename any class in the Explorer to match its contents.
- Radius: The radius within which a point in the point cloud will be considered as a power line and therefore will be classified as such. For thick power lines, use a larger radius.
Clash detection
The clash detection tool is similar to the classify tool, except in this case any objects which are close to the power lines will be colorized to allow its visualization. This can be quite useful to detect nearby trees, branches, poles, or any other type of obstruction.
- Class: Select the class
- Skip class: Select the class you want the software to skip so it will be ignored during the clash detection process
- Class for intrusion zone: Select the classes you want the software to look into for the intrusion
- Intrusion zone: Here you will select the type of intrusion you want to check. You have the option between ''Radial'', ''Quadratic'' and ''Conical''. Once selected just enter the appropriate dimension.
Detected zone
Once the clash detection process is over, go to the ''Detected zone'' tab to check the results.
| Icon | Description |
|---|---|
| Deletes all selected objects in the item list |
| Colorization of the intrusion zone |
| Erase the colorized intrusion zone |
Pole detection
The pole detection tool will detect any cylindrical objects that appear along a detected power line. The detected objects will be added to the ''Detected Poles'' tab and provide you with their height and radius.
| Icon | Description |
|---|---|
 | Deletes all selected objects in the item list |
| Lets you manually add a pole by clicking a cylinder in the point cloud |
 | Will allow you to pick a pole on the screen and select it in the list |
| Will let you draw the cylinder on screen |
