Status flags are assigned to soundings during conversion, as determined from information provided by the specific acquisition format. When a Lidar sounding is converted into HIPS, it is given the following quality flags. These flags can be changed during processing.
This table shows the quality statuses that can be attached to a sounding.
Quality Flag | Description |
0 | The sounding has a detected depth only. The alternative depth is invalid. |
1 | The sounding has both a detected and a valid alternative depth. A quality control/assurance decision has not yet been made. |
2 | The sounding has a detected depth and a valid alternative depth, and the user has decided to keep the detected depth. |
3 | The sounding has both a detected and alternative value, but the alternative value has been swapped with the detected value). |
Selecting Detected and Alternative Data
In some instances, two depth values (detected and alternative) are returned. You can decide which depth value is most relevant and change the sounding's quality flag accordingly. This can be done in either the Swath Editor or the Subset Editor.
Soundings are highlighted in the colour that is set in the Tools > Options > Display > Editors > Lidar dialog box.
Command | Description |
Edit > Lidar > Highlight Alternative Depths | Soundings with a Quality flag of 1, 2, or 3 that contain valid alternative depths are highlighted. It does not select or superselect soundings.This command only highlights data in the Plan View. Select from three options: • View all alternative depths • Swap to alternative • Keep detected. |
Edit > Lidar > View Alternative Depths | This command refreshes the display so that the alternative depths for soundings with a Quality 1 flag are shown. This is a useful tool for viewing the position of alternative depths in relation to neighbouring soundings. |
Edit > Lidar > Swap to Alternative | This command applies an alternative depth in a superselected sounding with a Quality 1 flag.to the detected depth. With SHOALS data, the depth is swapped, and with LADS data, the depth and position are swapped. An asterisk beside the depth value indicates whether the detected or alternative depth is currently in the HIPS depth file |
Keep detected | This command is used to verify that the detected depth is preferred over the alternative depth (see Sounding Quality and Status Flags). 1. Select soundings and superselect a sounding with a Quality 1 flag. 2. Select the Keep Detected command. The Quality flag is changed to 2. |