readADCP_g

Description

readADCP_g is a utility for reading and processing RDI ASCII ADCP (Acoustic Doppler Current Profiler) files. It is a slightly simplified or earlier version of the more comprehensive readADCP tool. Its primary function is to convert raw ADCP data into a time-series profile, which is saved as a JHC-formatted image file.

The tool can visualize velocity magnitude, azimuth, or backscatter. It supports georeferencing via an external navigation file and can stack (average) data over a set number of ensembles or within geographic bins on a map.

Usage

readADCP_g -in <infiles> -out <outfile> [OPTIONS]

Key Options

Option	Description
`-in <infilename(s)>`	Required. One or more input RDI ASCII ADCP files.
`-out <outfile>`	Required. The prefix for the output filenames.
`-nav <navfile>`	Use an external OMG-HDCS navigation file for positioning.
`-use_adcp_nav`	Use the navigation data embedded within the ADCP files.
`-map <mapfile.map>`	Georeference and stack the output profiles onto a map grid.
`-pixel <size>`	The horizontal pixel size for the output map, if `-map` is used.
`-mindepth <m>` / `-maxdepth <m>`	Set the minimum and maximum depth range to process.
`-ref_bottom`	Reference depth layers relative to the seafloor instead of the sea surface.
`-layers <num>`	Set the number of vertical bins in the output profile. Default is 100.
`-draft <m>`	Specify the draft of the ADCP transducer to correct the depth values.
`-showMAG`	(Default) Display velocity magnitude in the output profile.
`-showBS`	Display backscatter intensity. Use with `-BSrange`.
`-showAZI`	Display velocity direction (azimuth).
`-maxcurrent <m/s>`	Set the maximum current for scaling the output image colors (for magnitude display).
`-BSrange <min> <max>`	Set the min/max backscatter values for color scaling.
`-ensem_stack <num>`	Average (stack) data over a specified number of ensembles.
`-stack_in_map`	When using `-map`, creates a single, averaged profile for all data falling within the map area.
`-headbias <deg>`	Apply a constant heading correction in degrees.
`-delay <sec>`	Apply a time delay in seconds to the data.
`-tidefile <tide.nav>`	Use an external navigation file to provide tidal height corrections.
`-phase_zero <Y J H M>`	Defines the reference start time for tidal phase calculations.
`-v`	Enable verbose output.

How It Works

Read Data: The tool reads ADCP data from the specified input files.
Georeferencing: If a -nav file is provided, it interpolates the navigation data to get a position for each ADCP ensemble. If -use_adcp_nav is specified, it uses the GPS data from within the ADCP file.
Data Extraction: For each ensemble, it extracts the selected data type (Magnitude, Azimuth, or Backscatter) for each depth bin.
Profile Generation: The vertical data for each ensemble is binned into a profile according to the -layers and depth range settings. This profile becomes one column in the output time-series image.
Output: The generated profile is written to the output file (<outfile>.prof). The process is repeated for every ensemble, building the image column by column.
Stacking/Mapping: If -ensem_stack or -map options are used, the tool performs averaging either over time or space before writing the final output.

This tool provides a “lite” version of the functionality found in readADCP, focusing on the core task of creating profile images from raw ADCP files.