Lesson 1: Visualize 3DEP Lidar Data with uniDEM

1. Click uniDEM icon
2. Click Load LIDAR
3. Open the unzipped working data folder
4. Select both LAZ files
5. Click Open

1. Click OK to maintain LAS v1.2
2. Click Yes to all files into single dataset
3. Enter Madison for the combined dataset name
4. Data is displayed in the Table Of Contents (TOC)

1. Right Click Madison in the TOC
2. Click Check All

1. Lidar points for both files are displayed top down (2D)
2. Points are colored based on the LAS classification in the point metadata

Notes:

• Points density and display size are set conservatively by default (see next step)
• If no Class exists points are colored by elevation

1. Click the LIDAR tab
2. Click the Point Size dropdown and set to large.
3. Click the Density dropdown to render more or less points
   Note: Increasing density reduces render rates

uniDEM strides lidar points for rendering performance.

1. Click into data view
2. Rotate: Right click and move mouse left or right
3. Tilt Right click and move mouse up or down
4. Move: Left click and move mouse in any direction
5. Zoom: Scroll wheel mouse forward/backward
6. Toggle 2D/3D: Press key 2 and 3

Place the cursor is placed over a lidar point to see point details above the cursor and in the TOC.

1. Lidar class is displayed over cursor
2. Elevation (Z)is displayed over cursor
3. Source Lidar file is displayed in TOC
4. Lidar Class is displayed in TOC
5. LAS metadata including:
   • Edge of Flight
   • Intensity
   • Keypoint
   • Point Source ID
   • Return
   • Scan Angle Rank
   • Scan Direction
   • Synthetic
   • Time
   • User Data
   • Withheld
   • Overlap (LAS v1.4)

1. Click LIDAR tab
2. Click Class Profile button
3. Click OK to use the Madison dataset
4. Click Select All to select both LAZ files
5. Click OK

The dialog presents the following information:

• Total number of points
• Each LAS Class type in the selected datasets
• The count for each LAS class

Note: This project contains misclassifications, for example buildings are classified as Medium Vegetation (4) and Overlap as Reserved For ASPRS (11).

1. Press r on keyboard to enable rectangle drawing tool
2. Hold Shift + Left click while moving mouse to draw a rectangle
3. Click Class Profile button
4. Click OK to use the Madison dataset
5. Click Select All to select both LAZ files
6. Click OK

The dialog presents the following information for only points within the rectangle:

• Total number of points
• Each LAS Class type in the selected datasets
• The count for each LAS class

Note: This project contains misclassifications, for example buildings are classified as Medium Vegetation (4) and Overlap as Reserved For ASPRS (11).

1. Click LIDAR tab
2. Click Show/Hide Classes button
3. Click Ground (2) in the selection dialog
4. Hold Ctrl and click Water (9) in the selection dialog
5. Click OK

The view turns off all lidar points that are not of class Ground(2) or Water (9).

Notes:

1. The remaining points are remain loaded, but not visible
2. Independent data views can present different classes

1. Within the LIDAR tab
2. Click Color button
3. Select Color By Elevation
4. Click OK to use the Madison dataset
5. Click Select All to use both LAZ files
6. Click OK
7. Click OK to select the Jet color scheme
8. Click OK to select Auto color scale
9. Click OK to use 1 as the lowest percentile
10. Click OK to use 99 as the lowest percentile

1. Within the LIDAR tab
2. Click Color button
3. Select Color By Intensity
4. Click OK to use the Madison dataset
5. Click Select All to use both LAZ files
6. Click OK
7. Select Gray from the drop down in the color scheme dialog
8. Click OK to select Auto color scale
9. Click OK to use 1 as the lowest percentile
10. Click OK to use 99 as the lowest percentile