This document describes HydrOffice QC Tools 4.9.9.

2.5. Info Tab

The Info tab contains numerous helpful links and utilities (Fig. 2.63):

  • The HydrOffice QC Tools website

  • The Online User Manual

  • The Offline User Manual (PDF)

  • A User Bug Report Tool

  • The HydrOffice Main Page

  • The NOAA Nautical Charts Home Page

  • The Center for Coastal and Ocean Mapping Main Page

  • The University of New Hampshire Main Page

  • Uncertainty Calculator

  • The Rock or Islet oracle

  • NOAA S-57 Support Files for CARIS

  • License Information

  • Contacts List

  • QC Tools Software Information


info tab full

Fig. 2.63 The Info tab



2.5.1. RorI: Your Rock-or-Islet Oracle


2.5.1.1. How To Use?


RorI has been created as a tool to help hydrographers determine if their feature is a rock or an islet. RorI is a standalone tool that is launched from the button at the top of the Info tab (Fig. 2.64).


info tab rori gui

Fig. 2.64 The RorI interface.


2.5.1.2. How Does It Work?


At the top of RorI, the Depth/Elevation toggle does not have an impact on how RorI is doing its calculations (Fig. 2.65). The toggle controls two visualizations. First, the boxes below which show you the limits that define the different WATLEV values. You can either view these values in an elevation (positive up) or depth (positive down). The boxes below show the limits behind of each WATLEV value which are derived from NOAA’s Hydrographic Specifications and Deliverables.


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Fig. 2.65 The RorI settings and inputs.


Chart Datum is the water level reference on a nautical chart. Typically MLLW, except for the Great Lakes and connecting waterways, which use LWD.

SPOR is the shoreline plane of reference, the vertical datum accepted as the reference plane for shoreline, typically Mean High Water (MHW).

The user will then enter two very important pieces of information: the MHW value and the depth of the feature. The hydrographer will retrieve the MHW value from their tide note. The feature shall be tidally corrected and be referenced to MLLW. That means all depths above MLLW shall be negative! Note for the Great Lakes, all data is referenced to LWD, therefore there is no input needed by the user.

Next, RorI will crunch the numbers and tell you if your feature is a rock or islet (Fig. 2.66). If it is a rock, it will let you know its depth (VALSOU) and water level effect (WATLEV). If your feature is an islet, it will reference the elevation (ELEVAT) to MHW (LWD for the Great Lakes).

RorI does not use magic to calculate the difference between a rock or an islet. What it does is some simple math. The tool compares the depth to the MHW value (or LWD for the Great Lakes) which are both entered by the user. If the rock is higher in elevation than 0.1 m, then it is an islet.

RorI is based on the following specifications:

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Fig. 2.66 The RorI outputs.


RorI also helps the hydrographer visualize the difference between a rock and an islet for their survey using a graphic.



2.5.2. Uncertainty Calculator


2.5.2.1. How To Use?


Uncertainty Calculator is a standalone tool to help you calculate the total vertical uncertainty and total horizontal uncertainty of hydrographic data (Fig. 2.68).

To launch the tool, click the button at the top of the Info tab (Fig. 2.67).

info tab uncertainty calculator

Fig. 2.67 The Uncertainty Calculator button in the Info tab.

The user can select among different NOAA and IHO (S-44 and S-57) quality metrics. Optionally, the user can select a second quality metric for performing a direct comparison. Once that the user set the input depth and click on the Run button, the uncertainty requirements are displayed.

info tab uncertainty calculator gui

Fig. 2.68 The Uncertainty Calculator interface.


2.5.2.2. How Does It Work?


Uncertainty calculations are based on NOAA Quality Metric, S-44 Orders, and S-57 CATZOC uncertainties as described below:

NOAA HSSD

TVU\, QC = a + (b * depth)

where:

  • a = 0.15 m, b = 0.0075 for NOAA Exceptional

  • a = 0.25 m, b = 0.0075 for NOAA Critical

  • a = 0.5 m, b = 0.01 for NOAA General 1

  • a = 1.0 m, b = 0.02 for NOAA General 2

  • a = 1.0 m, b = 0.02 for NOAA General 3

  • a = 2.0 m, b = 0.05 for NOAA General 4

THU\, QC = k + p * depth

where:

  • k = 1 m, p = 0 pct for NOAA Exceptional

  • k = 2 m, p = 0 pct for NOAA Critical

  • k = 5 m, p = 5 pct for NOAA General 1

  • k = 20 m, p = 10 pct for NOAA General 2

  • k = 50 m, p = 0 pct for NOAA General 3

  • k = 500 m, p = 0 pct for NOAA General 4


IHO S-44

TVU\, QC = \sqrt{a^2 + (b * depth)^2}

where:

  • a = 0.15 m, b = 0.0075 for IHO Exclusive Order

  • a = 0.25 m, b = 0.0075 for IHO Special Order

  • a = 0.5 m, b = 0.013 for IHO Order 1a & 1b

  • a = 1.0 m, b = 0.023 for IHO Order 2

THU\, QC = k + p * depth

where:

  • k = 1 m, p = 0 pct for IHO Exclusive Order

  • k = 2 m, p = 0 pct for IHO Special Order

  • k = 5 m, p = 5 pct for IHO Order 1a & 1b

  • k = 20 m, p = 10 pct for IHO Order 2


IHO S-57 CATZOC

TVU\, QC = a + (b * depth)

where:

  • a = 0.5 m, b = 0.01 for CATZOC A1

  • a = 1.0 m, b = 0.02 for CATZOC A2

  • a = 1.0 m, b = 0.02 for CATZOC B

  • a = 2.0 m, b = 0.05 for CATZOC C

THU\, QC = k + p * depth

where:

  • k = 5 m, p = 5 pct for CATZOC A1

  • k = 20 m, p = 0 pct for CATZOC A2

  • k = 50 m, p = 0 pct for CATZOC B

  • k = 500 m, p = 0 pct for CATZOC C

The graph at the bottom of the tool is interactive and visually represents the total vertical and total horizontal uncertainties at that order. If the user wants to compare different uncertainty specifications, you can select a second quality metric in the “Quality Metric #2” and a second line will appear in blue.



2.5.3. BAG xyz


2.5.3.1. How To Use?


Export elevation values as a point cloud.

  • Add 1 or more BAG files in Inputs.

  • Choose the coordinate reference system that the user would like the file to be exported. The user may keep the original coordinate reference system, convert to Geographic WGS84, or convert to a specific EPSG code using the radio buttons.

  • Choose the Z convention of either Depth (positive down) or Elevation (positive up).

  • The user optionally can choose to truncate the depth after a specific decimal place.

  • The user may also choose the output order of the latitude/northing, longitude/easting, and depth/elevation to suit their needs.

  • In Execution (Fig. 2.69), click Export as XYZ.

../../_images/info_tab_bag_xyz.png

Fig. 2.69 BAG XYZ’s interface.

  • After computing, the output window opens automatically.



2.5.3.2. How Does It Work?


A text file with three columns is created.