Operators

In Echoview, an operator is an algorithm which acts upon an operand to produce a virtual variable. The operators implemented in Echoview have been chosen for their generality to allow maximum flexibility in visualizing and analyzing data. All operators are licensed with the Advanced Operators module, except those indicated in Operator licensing in Echoview.

Notes:

Operator classification

Echoview operators are classified into the following groups, based on their function

Arithmetic

Operator

Description

Code

The multi-threaded Code operator allows you to apply a Python® script from a *.py file to specified operands. Echoview supports and includes the Python NumPy and SciPy modules which offer a wide range of open-source scientific computing and numerical integration capabilities. The Code operator is licensed under the Advanced Operators module.

The Code operator outputs a ping for each matched operand ping. The data type of the output is the same as the operand. However, the Complex power dB, Complex Sv, Complex TS, Pulse compressed complex power dB, Pulse compressed complex Sv, Pulse compressed complex TS data types are output as single beam Sv, TS and power respectively. Calculations are carried out in the domain specified by the Python file.

See also: Code settings and further notes.

Operand 1
  • Angular position
  • Boolean
  • Complex angular position
  • Complex power dB
  • Complex Sv
  • Complex TS
  • Linear
  • Multibeam angular position
  • Multibeam boolean
  • Multibeam magnitude
  • Multibeam phase
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Pulse compressed complex angular position
  • Pulse compressed complex power dB
  • Pulse compressed complex Sv
  • Pulse compressed complex TS
  • Sv
  • TS
  • Unspecified dB

 

Constant divide

This operator divides a variable by a constant number. The Constant divide operator is licensed under the Advanced Operators module.

See also: Constant Divide settings and further notes.

Operand 1
  • Color
  • Linear
  • Multibeam color
  • Multibeam magnitude
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Sv
  • TS
  • Unspecified dB

 

Constant multiply

This operator multiplies a variable by a constant number. The Constant multiply operator is licensed under the Advanced Operators module.

See also: Constant Multiply settings and further notes.

Operand 1
  • Color
  • Linear
  • Multibeam color
  • Multibeam magnitude
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Sv
  • TS
  • Unspecified dB

Current velocity magnitude

This operator returns the magnitude of the current velocity given three orthogonal current velocity component variables. The resultant acoustic virtual variable has a linear data type. The Current velocity magnitude operator is licensed under the Advanced Operators module.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2

Operand 3

  • Current velocity component

  • Current velocity component

  • Current velocity component

Formula

This operator runs an arbitrary mathematical equation on a per-sample basis on the echogram data. The Formula operator is licensed under the Advanced Operators module. The operator may handle many operands.

See also: Formula settings and further notes.

Operand #
  • Angular position
  • Boolean
  • Linear
  • Multibeam angular position
  • Multibeam boolean
  • Multibeam magnitude
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Sv
  • TS
  • Unspecified dB

Linear minus

This operator subtracts two variables in the linear domain. Operand 2 is subtracted from Operand 1.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Sv
  • TS
  • Unspecified dB

Linear plus

This operator adds two variables in the linear domain.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Sv
  • TS
  • Unspecified dB

Maximum

This operator returns the maximum data point values from two variables.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2
  • Color
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Color
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB

 

Note: For color variables, comparisons are made using the sum of the red, green and blue channels. If these values are equal, the value from operand 1 is returned.

Mean of 3

This operator takes the mean of three variables.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2

Operand 3
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB

 

Note: The mean for SV, TS and unspecified dB variables is calculated in the linear domain.

Minus

This operator subtracts two variables. Operand 2 is subtracted from Operand 1.

Echoview accepts operands of the following data types as input:

Operand 1

Operand 2
  • Color
  • Complex power dB
  • Complex Sv
  • Complex TS
  • Linear
  • Multibeam color
  • Multibeam magnitude
  • Multibeam phase
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Pulse compressed complex power dB
  • Pulse compressed complex Sv
  • Pulse compressed complex TS
  • Sv
  • TS
  • Unspecified dB
  • Color
  • Complex power dB
  • Complex Sv
  • Complex TS
  • Linear
  • Multibeam color
  • Multibeam magnitude
  • Multibeam phase
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Pulse compressed complex power dB
  • Pulse compressed complex Sv
  • Pulse compressed complex TS
  • Sv
  • TS
  • Unspecified dB

Notes:

  • Output for ping 0 is no data for the case where the Operand 2 variable is made up of all no data pings.
  • Effect of No data samples on the Wideband Frequency Response graph page.

Minimum

This operator returns the minimum data point values from two variables.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2
  • Color
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Color
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB

 

Note: For color variables, comparisons are made using the sum of the red, green and blue channels. If these values are equal, the value from Operand 1 is returned.

Plus

This operator adds two variables.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2
  • Color
  • Complex power dB
  • Complex Sv
  • Complex TS
  • Linear
  • Multibeam color
  • Multibeam magnitude
  • Multibeam phase
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Pulse compressed complex power dB
  • Pulse compressed complex Sv
  • Pulse compressed complex TS
  • Sv
  • TS
  • Unspecified dB
  • Color
  • Complex power dB
  • Complex Sv
  • Complex TS
  • Linear
  • Multibeam color
  • Multibeam magnitude
  • Multibeam phase
  • Multibeam Sv
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Pulse compressed complex power dB
  • Pulse compressed complex Sv
  • Pulse compressed complex TS
  • Sv
  • TS
  • Unspecified dB

Notes:

  • Output for ping 0 is no data for the case where the Operand 2 variable is made up of all no data pings.
  • Effect of No data samples on the Wideband Frequency Response graph page.

Variance of 3

This operator takes the variance of three variables.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2

Operand 3
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB
  • Linear
  • Power dB
  • Sv
  • TS
  • Unspecified dB

 

Note: The variance for SV, TS and unspecified dB variables is calculated in the linear domain.

Bitmap

Operator

Description

And

This operator does a logical AND on two bitmaps.

Echoview accepts operands of the following data types as input:
 

Operand 1

Operand 2

  • Boolean

  • Multibeam boolean

  • Boolean

  • Multibeam boolean

Line bitmap

This operator is used to create a bitmap of the area between two specified lines.
The input variable is used to determine the ping times and ping geometry.

Operand 1
  • Angular position
  • Boolean
  • Color
  • Complex angular position
  • Complex power dB
  • Complex Sv
  • Complex TS
  • Linear
  • Power dB
  • Pulse compressed complex angular position
  • Pulse compressed complex power dB
  • Pulse compressed complex Sv
  • Pulse compressed complex TS
  • Sv
  • TS

  • Unspecified dB

See also: Line Bitmap settings and notes.

Line range bitmap

This operator creates a bitmap using the ping geometry of Operand 1. Every datapoint in each output ping will be true if the line depth (from Operand 2) at the time of that ping was within the specified limits, and false otherwise.

Operand 1

Operand 2
  • Angular position
  • Boolean
  • Color
  • Complex angular position
  • Complex power dB
  • Complex Sv
  • Complex TS
  • Current velocity

  • Linear

  • Multibeam angular position
  • Multibeam boolean
  • Multibeam color
  • Multibeam magnitude
  • Multibeam phase
  • Multibeam SV
  • Multibeam TS
  • Multibeam unspecified dB
  • Power dB
  • Pulse compressed complex angular position
  • Pulse compressed complex power dB
  • Pulse compressed complex Sv
  • Pulse compressed complex TS
  • SV
  • TS
  • Unspecified dB
  • Line

    • See also: Line range bitmap and notes.

    Mask

    This operator applies a bitmap mask to another variable. Data corresponding to true values in the bitmap are unchanged. Data corresponding to false values in the bitmap will be converted to the value specified on the Mask page of the Variable Properties dialog.

    All operands must be exclusively single beam or multibeam.

    Operand 1

    Operand 2
    • Angular position
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Multibeam angular position
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • TS
    • Unspecified dB
  • Boolean
  • Multibeam boolean

    • See also: Mask settings and notes.

    Not

    This operator applies a Boolean NOT operation to the individual values in a Boolean variable, i.e. it changes true values to false and vice versa.

    Operand 1
    • Boolean
    • Multibeam boolean

     

    Or

    This operator does a logical OR on two bitmaps.

    Operand 1

    Operand 2

    • Boolean

    • Multibeam boolean

    • Boolean

    • Multibeam boolean

    Data range bitmap

    This operator creates a bitmap (Boolean or multibeam Boolean variable) with a "true" value for each input value that is within a specified range, and a "false" value for each input value that is outside the specified range. "No data" values are always translated to "false".

    Operand 1
    • Angular position
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Multibeam angular position
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    See also: Data Range Bitmap settings and notes.

    Motion range bitmap

    This operator creates a bitmap using the ping geometry of Operand 1. Every datapoint in each output ping will be true if the roll, pitch or heading (from Operand 2) at the time of that ping was within the specified limits, and false otherwise.

    Operand 1

    Operand 2
    • Angular position
    • Boolean Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam SV
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • SV
    • TS
    • Unspecified dB
    • Heading
    • Pitch
    • Roll

     

    See also: Motion Range Bitmap settings and notes.

    Region bitmap

    This operator is used to create a bitmap of the area corresponding to regions of specified type and/or classification. The input variable is used to determine the ping times and ping geometry.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

     

    See also: Region Bitmap settings and notes.

    Select

    This operator uses a bitmap to select between values from two other variables.

    If there is a true value in the bitmap then the corresponding data value from the first variable will be used at that position, otherwise the corresponding data value from the second variable will be used.
     

    Operand 1

    Operand 2

    Operand 3
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    • Boolean

    Target bitmap

    This operator creates a bitmap of pings which contain single target detections.

    The resulting virtual variable is a boolean variable with the same number of pings and ping geometry as the first Operand. Each sample in the result has a value of true if it is on the same ping as one or more single targets in the second Operand and false if not. See also Effect of No data samples on the Wideband Frequency Response graph page.

    Operand 1

    Operand 2
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB
    • Single targets

    Target samples bitmap

    This operator creates a Boolean (bitmap) variable which has the same ping geometry as the first Operand. The datapoint values are false, when samples on a ping in the first Operand do not fall within the range of a single target (specified by the Near margin and Far margin) in the corresponding ping of the second Operand.

    Operand 1

    Operand 2
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB
    • Single targets

     

    See also: Target Samples Bitmap settings and notes.

    Trained model bitmap (experimental)

    This operator creates a bitmap using a trained inference model that represents a chosen feature in an acoustic variable. This is an experimental operator that uses machine learning techniques.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

     

    See also: Trained model bitmap (experimental) settings and notes.

    Conversion

    Operator

    Description

    dB to linear

    This operator converts dB values in an input variable to linear values using the formula:

    linear = 10 (dB / 10)

    Operand 1
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    Type conversion

    This operator is used for changing the data type of a variable to a different data type. This operator does not, by itself, change the input variable. However, any settings specified on the Data page of the Variable Properties dialog box will be applied.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • Target length
    • TS
    • Unspecified dB

     

    See also: Type Conversion settings and notes.

    Linear to dB

    This operator applies linear to dB conversion to the individual values in the input variable using the formula:

    dB = 10 × log10(linear)

    Zero or negative input values are converted to "no data" values.

    Operand 1
    • Linear 
    • Multibeam Magnitude

    Sv to TS

    This operator applies Sv to TS conversion to the individual dB values in the input variable.

    Operand 1
    • Complex Sv
    • Pulse compressed complex Sv
    • Sv

    See also: Sv to TS settings and notes.

    TS to Sv

    This operator applies TS to Sv conversion to the individual dB values in the input variable.

    Operand 1
    • Complex TS
    • Pulse compressed complex TS
    • TS

    See also: TS to Sv settings and notes.

    Current velocity component to linear conversion

    This operator returns the magnitude of the current velocity given three orthogonal current velocity component variables.

    Operand 1

    Operand 2

    Operand 3
    • Current velocity
    • Current velocity

    • Current velocity

     

    Convolution

    The Convolution operators group lists single beam convolution operators. Multibeam convolution operators are listed under Multibeam operators.

    For more information about convolution operators, their differences, and how they are used, see Convolution algorithms and Convolution operators illustrated.

    Operator

    Description

    3x3 convolution

    This operator applies a user-specified 3x3 convolution matrix to the echogram.

    Operand 1
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: 3x3 Convolution settings and notes.

    5x5 convolution

    This operator applies a user-specified 5x5 convolution matrix to the echogram.

    Operand 1
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: 5x5 Convolution settings and notes.

    7x7 convolution

    This operator applies a user-specified 7x7 convolution matrix to the echogram.

    Operand 1
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: 7x7 Convolution settings and notes.

    XxY convolution

    This operator applies an XxY convolution algorithm to the echogram.

    Operand 1
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: XxY Convolution settings and notes.
    XxY statistic

    This operator applies an XxY statistic filter to the echogram.

    Operand 1
    • Boolean
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: XxY Statistic settings and notes.

    XxYxZ convolution

    This operator applies an XxYxZ convolution algorithm to the echogram.

    Operand 1
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: XxYxZ Convolution settings and notes.

    XxYxZ statistic

    This operator applies an XxYxZ statistic filter to the echogram.

    Operand 1
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: XxYxZ Statistic settings and notes.

    Blur

    This operator applies a standard 3x3 convolution matrix to blur the image.

    The convolution kernel used in the Blur operator is:

    1

    2

    1

    2

    1

    2

    1

    2

    1

     

    Operand 1
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    Notes:

    Dilation filter n × n

    This operator applies an n × n dilation convolution filter to the echogram (where n = 3, 5 or 7).

    A dilation filter replaces each data point with the maximum of the data points in the surrounding cell.

    Operand 1
    • Boolean
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    Notes:

    Erosion filter n × n

    This operator applies a n × n erosion filter to the echogram (where n = 3, 5 or 7).

    An erosion filter replaces each data point with the minimum of the data points in the surrounding cell.

    Operand 1
    • Boolean
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    Notes:

    Median filter n × n

    This operator applies a n × n median filter to the echogram (where n = 3, 5 or 7).

    A median filter replaces each data point with the median of the data points in the surrounding cell.

    Operand 1
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    Notes:

    Sharpen

    This operator applies a standard 3 × 3 convolution matrix to sharpen the image.

    The convolution kernel used in the Sharpen operator is:

    -1

    -1

    -1

    -1

    9

    -1

    -1

    -1

    -1

     

    Operand 1
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    Notes:

    Data manipulation

    Operator

    Description

    Attenuated signal removal

    This operator identifies pings which show an attenuated signal strength when compared to the surrounding pings. The operator is based on the “attenuated signal filter” algorithm and definitions described in Ryan et al. (2015).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    See also: Attenuated Signal Removal settings and notes.

    Background noise estimation

    This operator estimates the background-noise level. Background noise manifests as a ‘TVG rainbow’ on an echogram. The operator is based on the algorithm and definitions described in De Robertis & Higginbottom (2007).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS

    See also: Background Noise Estimation settings and notes.

    Background noise removal

    This operator estimates the background-noise level and subtracts it from the value of each sample. Background noise manifests as a ‘TVG rainbow’ on an echogram.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS

    See also: Background Noise Removal settings and notes.

    Calibration subset

    This operator creates a variable containing the subset of pings that have a specified calibration value.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB

    See also: Calibration Subset settings and notes.

    Cell statistic

    This operator produces an output variable with samples set based on a statistic calculated from each cell.

    Operand 1
    • Sv

    See also: Cell Statistic settings and notes.

    Cell statistic - Single targets

    This operator produces an output variable with samples set based on a statistic calculated from each cell. Operand 2 is used to provide the geometry for the output ping, but note that ping times must still match.

    Operand 1

    Operand 2
    • Single targets
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Sv
    • TS
    • Unspecified dB

    See also: Cell Statistic - Single targets settings and notes.

    Copy

    This operator copies a variable. It does not change the input variable, but any settings specified on the Data page of the Variable Properties dialog box will be applied.

    The resulting virtual variable can be useful for:

    • displaying the "same" variable simultaneously with different display or processing settings

    • thresholding purposes

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Matrix angular positon
    • Matrix Sv
    • Matrix TS
    • Matrix unspecified dB
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB

    Note: See also Effect of No data samples on the Wideband Frequency Response graph page.

    Data generator

    This operator is used to create data pings. It can create pings with constant values using a specified value. It can also create Sv and TS pings with time-varied gain (TVG), based on the Sv or TS value at 1 meter and a specified absorption coefficient. The input variable is used to determine the ping times and ping geometry.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    See also: Data Generator settings and notes.

    Deadzone estimation

    This operator calculates estimations for the Sv values in the deadzone, a zone on the echogram specified by two lines. Each data sample in the deadzone is replaced by the average of all values in a layer with specified thickness above the deadzone.

    Operand 1
    • Sv

    See also: Deadzone Estimation settings and notes.

    Extract bottom feature

    This operator extracts a Bottom Classification feature from an acoustic variable with a specified Bottom line under Bottom settings on the Analysis page of the Variable Properties dialog box.

    The output is virtual bottom feature line data that may be viewed as a table, graph or export .csv file. The Extract bottom feature virtual variable is supported by live viewing.

    Operand 1
    • Complex Sv
    • Pulse compressed complex SvS
    • Sv

    See also: Bottom Feature settings and notes.

    Extract transmission characteristic

    This operator extracts a variable for a nominated transducer transmission characteristic and component.

    Operand 1
    • Transmission characteristics

    See also: Extract Transmission Characteristic settings and notes.

    FIR filter
    (Finite Impulse Response)

    This operator implements a finite impulse response filter. It returns a weighted average of the current and previous pings.

    Operand 1
    • Linear
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: FIR Filter settings and notes.

    IIR filter
    (Infinite Impulse Response)

    This operator implements an infinite impulse response filter. It returns a weighted average of the current ping and the calculated previous ping.

    Operand 1
    • Linear
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: IIR Filter settings and notes.

    Impulse noise removal

    This operator identifies and adjusts sample values that are significantly higher than those of surrounding samples at the same depth.

    Based on the combination of settings applied, it can be used to adjust the value of samples that are affected by impulse noise such as interference from other sonars (which manifest as short ‘flecks’ on an echogram). Care is required to prevent it from adjusting good data.

    The operator is based on the “impulsive noise (IN)” algorithm and definitions described in Ryan et al. (2015).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS

    See also: Impulse Noise Removal settings and notes.

    Join opposing pings

    Joins the ping data from two transducers which are pinging in opposite directions. The ping data from Operand 2 is projected onto the ping data from Operand 1.

    Operand 1

    Operand 2
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: Join Opposing Pings settings and further notes.

    Live export

    This operator incrementally exports its data to a file during live viewing.

    Operand 1
    • Color
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: Live Export settings and notes.

    Match geometry

    Creates a virtual variable that takes data from Operand 1 and the Start range, Stop range, and Number of data points from Operand 2. In effect, it enables you to resample Operand 1 to the exact ping geometry of Operand 2. The resampling is a weighted mean calculation. This virtual variable is useful to change resampled data back to its original ping geometry.

    Notes:

    • Ping times for operands 1 and 2 must match. See also: Match ping times operator.
    • Echoview offers various Resample operators with more sampling options.

    Operand 1

    Operand 2
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Sv
    • TS
    • Unspecified dB

    See also: Match geometry algorithm.

    Match ping times

    This operator selects pings from the first Operand in such a way as to match the times of the pings in the second Operand.

    Operand 1

    Operand 2
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB

    See also: Match Ping Times settings and notes.
    Merge GPS

    This operator merges the position data in two variables to create a single position variable. You can use Merge GPS to merge position data from multiple filesets to partner processed and merged echogram data from multiple filesets.

    Echoview accepts operands of the following data types as input:
     

    Operand 1

    Operand 2
    • Position
    • Position

    Notes:

    • In the resulting virtual variable, position data are ordered according to time.

    • In the case that position data in both input variables have exactly the same times, the position data from the second variable will be assigned a time 1ms after its original time.

    Merge pings

    This operator merges the data in two variables of the same data type to create a single variable containing the pings from both the input variables.

    Examples of use:

    • merge multiplexed raw variables collected with compatible transducer settings
    • merge corrected data; data may have been time-corrected or corrected in another way

    Operand 1

    Operand 2
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB

     

    Notes:

    • In the resulting virtual variable, pings are ordered according to time.
    • In the case that pings in both input variables have exactly the same times, the ping from the second variable will be assigned a time 1ms after its original time. If that time already exists in the virtual variable, Merge pings will add another 0.1 second until a unique and non-identical time is achieved.
    • See also Effect of No data samples on the Wideband Frequency Response graph page.

    Motion correction (Dunford method)

    This operator compensates sample values for attenuation due to changes in orientation of the transducer between the time of the transmitted pulse and the time of each sample's reception.

    Operand 1

    Operand 2

    Operand 3
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Roll
    • Pitch

    See also: Motion correction (Dunford method) settings and notes.

    Ping subset

    This operator creates a variable containing a specified subset of the pings in another variable.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB

    See also: Ping Subset settings and notes.

    Ping time shift

    This operator makes a copy of another variable, shifting the time on each ping by a specified time or to times corresponding to a relative ping index.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB

    See also: Ping Time Shift settings and notes.

    Processed data

    This operator applies the exclusions (line and surface) and bad data analysis settings specified on the Analysis page of the Variable Properties dialog box for its input variable. Changes may include: data points to 'no data' values, special handling for Thickness mean calculations and data points to empty water values. For more detailed information refer to About analysis domains. Also note the Effect of No data samples on the Wideband Frequency Response graph page.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • TS
    • Unspecified dB

     

    Reduce pings

    This operator is used to remove pings which meet certain criteria.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • TS
    • Unspecified dB

    Notes:

    • Single target pings are dropped if they have no targets.
    • Other pings are removed if:
      • they have no data points, or
      • all values are black (color), all values are false (Boolean), or all values are 'no data' (Sv, TS, dB, linear, current velocity or angle).
    • The number of pings in the Reduced pings echogram can be equal to or less than the input operand.
    • The Reduce pings (method 2) operator removes pings in a similar way, and can offer savings in display time, however, no-data pings are used at the end of the echogram and this causes an incorrect NASC for the last cell.
    • See also Effect of No data samples on the Wideband Frequency Response graph page.

    Reduce pings (method 2)

    This operator is used to remove pings which meet certain criteria. With respect to the 'reduced pings' for display and export, the Reduce pings and Reduce pings (method 2) operators are identical.

    The differences with the method 2 operator are:

    • The faster display speed. Pings are calculated only when they are required. In the case where a section of the echogram is displayed, the time savings can be significant. Hence, the method 2 operator can be useful in developing and testing virtual variable chains.
    • The method 2 operator differs from the Reduce pings operator in that the method 2 echogram has the same number of pings as the input operand, but the data is padded with no data values for the number of pings removed by the Reduce pings algorithm. The NASC calculation for the last cell or any region that extends into the last pings of a Reduce pings (method 2) echogram will be incorrect. To avoid the calculation error, you can use the Ping subset operator to remove the no data pings at the end of the echogram (used for padding).

     

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • TS
    • Unspecified dB

    Notes:

    • Single target pings are dropped if they have no targets.
    • Other pings are removed if:
      • they have no data points, or
      • all values are black (color), all values are false (Boolean), or all values are 'no data' (Sv, TS, dB, linear, current velocity or angle)
    • The Reduce pings operator removes pings in the same way but the number of pings in the echogram is generally less than the input operand.
    • See also Effect of No data samples on the Wideband Frequency Response graph page.

    Region statistic

    This operator is used to fill the datapoints in matching regions with a statistic calculated on the first Operand for those regions. Datapoints in overlapping matching regions will be assigned a "no data" value.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    See also: Region Statistic settings and notes.

    Resample by distance interval

    This operator resamples the input variable using a fixed distance interval in the time/distance domain, and a specified upper range, lower range and number of datapoints in the range domain. You may choose to sample all datapoints, or only those from the ping at the center of each interval. A mean, median, maximum, minimum or percentile resampling operation can be performed.

    Operand 1
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: Resample by Distance Interval settings and notes.

    Resample by number of pings

    This operator resamples the input variable using a fixed number of pings in the time/distance domain, and a specified upper range, lower range and number of datapoints in the range domain. You may choose to sample all datapoints, or only those from the ping at the center of each interval. A mean, median, maximum, minimum or percentile resampling operation can be performed.

    Operand 1
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: Resample by Number of Pings settings and notes.

    Resample by time interval

    This operator resamples the input variable using a fixed time interval in the time/distance domain, and a specified upper range, lower range and number of datapoints in the range domain. You may choose to sample all datapoints, or only those from the ping at the center of each interval. A mean, median, maximum, minimum or percentile resampling operation can be performed.

    Operand 1
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

     

    See also: Resample by Time Interval settings and notes.

    Resample multibeam pings

    This operator resamples the input variable using a fixed number of beams (with specified minimum/maximum beam angles) and a fixed number of datapoints (with specified start/stop range). A mean, median, maximum, minimum or percentile resampling operation can be performed.

    The resampled virtual variable can then be used with multibeam operators (e.g., Multibeam Background Removal) that require a regular ping geometry across pings.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Resample multibeam settings and notes.

    Signal to background noise ratio

    This operator estimates the ratio between the signal and the background-noise level for each sample in decibels. Background noise manifests as a ‘TVG rainbow’ on an echogram.

    The operator is based on the algorithm and definitions described in De Robertis & Higginbottom (2007).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Multibeam Sv
    • Multibeam TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS

    See also: Signal to Background Noise Ratio settings and notes.

    Threshold

    This operator compares datapoint values from two variables. If the Maximum or Minimum threshold is set and the value of a datapoint in Operand 1 is greater or less than the corresponding datapoint value from Operand 2 then the output datapoint is set to a thresholded value selected on the Variable Properties dialog. Otherwise it is set to the value of the datapoint from Operand 1.

    All operands must be exclusively single beam or multibeam.

    Operand 1

    Operand 2
    • Linear
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Linear
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: Threshold settings and notes.

    Towed body

    This operator is used to adjust the start ranges of pings using the depths of a specified line. It is designed for use with downwards-pointing transducers, and lines with positive depths.

    The Towed Body operator is only suitable in specific circumstances and has been superceded by heave support in the platform.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • TS
    • Unspecified dB

    See also: Towed Body settings and notes.

    Transect_subset

    This operator creates a variable containing a subset of the pings in another variable based on transects.

    Operand 1
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • TS
    • Unspecified dB

    See also: Transect subset settings and notes.

    Transient Noise Ping Removal

    This operator identifies pings which show an amplified signal strength when compared to the surrounding pings, typically associated with transient noise.

    The operator is based on the “attenuated signal filter” algorithm and definitions described in Ryan et al. (2015).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Multibeam Sv
    • Multibeam TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS

    See also: Transient Noise Ping Removal settings and notes.

     

    Transient Noise Sample Removal

    This operator identifies and adjusts sample values that are significantly higher than those of surrounding samples.

    Based on the combination of settings applied, it can be used to adjust the value of samples that are affected by transient noise such as sound generated by wave-hull collisions (which manifest as long ‘spikes’ on an echogram). Care is required to prevent it from adjusting good data.

    The operator is based on the “transient noise (TN)” algorithm and definitions described in Ryan et al. (2015).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Multibeam Sv
    • Multibeam TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS

    See also: Transient Noise Sample Removal settings and notes.

     

    Wideband frequency select

    This operator creates a single frequency echogram by suppressing all other frequency components from a wideband acoustic variable. The pulse length is not adjusted in the calculation for this operator, so when used with Sv data, it will result in lower values.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS

    See also: Wideband frequency select settings and notes.

     

    Wideband frequency subset

    This operator suppresses the components of the data which lie outside the requested frequency range, for a wideband acoustic variable. The pulse length is not adjusted in the calculation for this operator, so when used with Sv data, it will result in lower values.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS

    See also: Wideband frequency subset settings and notes.

     

    Imaging

    Operator

    Description

    3 color maximum

    This operator converts input values to a color, displaying the color for a sample from the operand with the maximum scaled value. All operands must be of the same data type.

    Operand 1

    Operand 2

    Operand 3
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also 3 Color Maximum settings and notes.

    GLCM texture feature

    This operator calculates Grey Level Co-occurrence Matrix features.

    Operand 1
    • Linear
    • Power dB
    • Sv
    • TS
    • Unspecified dB

    See also: GLCM Texture Feature settings, algorithms and notes.

    Monochrome

    This operator converts a color echogram to a luminance grayscale. It converts a color echogram to monochrome by averaging the red, green and blue color intensities using the equation:  

           Luminance = 0.2125 × Red + 0.7154 × Green + 0.0721 × Blue

    Operand 1
    • Color
    • Multibeam color

    Notes:

    • The color of data points in virtual variables created using this operator is not affected by the color scheme that is selected for the virtual variable, i.e. they are monochrome representations of the colors that are currently displayed on the operand. Other elements of the color scheme (e.g., lines and regions) are determined by the color scheme selected for the virtual variable.
    • Monochrome algorithm further details.

    Overlay

    This operator overlays two echograms to create a color image. The second echogram is laid over the first, so that the first is only visible where there are 'no data' values in the second echogram.

    Operand 1

    Operand 2
    • Boolean
    • Color
    • Linear
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Sv
    • TS
    • Unspecified dB
    • Linear
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Single targets
    • Sv
    • TS
    • Unspecified dB

    Note: The color of data points in virtual variables created using this operator is determined by the operands' color schemes, not by the color scheme of the selected for the virtual variable. Other elements of the color scheme (e.g., lines and regions) are determined by the color scheme selected for the virtual variable, see About setting variable properties for more information.

    To Color

    This operator converts an echogram to a color image. It assigns an RGB (red, green, blue) value to each data point.

    Operand 1
    • Angular position
    • Boolean
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Multibeam boolean
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

     

    Notes:

    • The color of data points in virtual variables created using this operator is determined by the operand's color scheme, not by the color scheme selected for the virtual variable. Other elements of the color scheme (e.g., lines and regions) are determined by the color scheme selected for the virtual variable, see About setting variable properties for more information.
    • See also Effect of No data samples on the Wideband Frequency Response graph page.

    Line

    The use of an exclusion line on wideband/complex data may affect the wideband frequency response. Refer to the Effect of No data samples on the Wideband Frequency Response graph page.

    Operator

    Description

    Arithmetic

    Creates a virtual line that is the arithmetic sum or difference of two lines, with the ping time stamps specified by Operand 1.

    Operand 1

    Operand 2

    Operand 3
    • Angular position
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Multibeam angular position
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB
    • Line

    • Line

    The settings for this operator are on the Arithmetic page of the Line Properties dialog box.

    Notes:

    • The Arithmetic operator may be used to remove heave from sounder-detected-lines that include it.

    Best bottom candidate line pick

    Creates a virtual line from an acoustic variable using the Best bottom candidate line pick algorithm and the settings on the Best candidate line pick page of the Line Properties dialog box.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

     

    For more information:

    Crop

    This operator creates a virtual line by cropping the input operand line at a specified minimum and maximum depth.

    Operand 1
    • Line

     

    The settings for this operator are on the Crop page of the Line Properties dialog box.

    Note: The Crop operator is useful to pre-process lines that you want to use with the Statistical combination line operator.

    Fixed depth

    Creates a virtual line with a fixed depth. The settings for this operator are on the Fixed depth page of the Line Properties dialog box. No operand is required.

    Linear offset

    Creates a virtual line that is linearly offset from another line.

    Operand 1
    • Line

     

    The settings for this operator are on the Linear offset page of the Line Properties dialog box.

    Maximum Sv line pick

    Creates a virtual line from an acoustic variable using a Maximum Sv line pick algorithm and the settings on the Maximum Sv Line Pick page of the Line Properties dialog box.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    For more information on the algorithm offered by this operator see the Line Pick algorithms page.
    Near-field depth estimation

    Creates a virtual line at the depth corresponding to the estimated on-axis range of the near field (Fresnel zone), multiplied by a factor (default is 2).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    Notes:

    • Echoview recomputes the near-field depth when you change the:
    • for Operand 1
    • This operator accounts for transducer and platform geometry.
    • The Multiply near-field range by setting on the Near-field Depth Estimation page is a factor by which to extend the near-field range that Echoview computes. The default is 2.
    • Where the operator encounters invalid Operand 1 ping data, the Near-field depth line status is set to None and a value of -10000.99.
      • Invalid cases include:
        • an unavailable value for frequency/major-axis 3dB beam angle/minor-axis 3dB beam angle
        • 0° for major-axis 3dB beam angle/minor-axis 3dB beam angle
    • CTD data is not supported.

    Off-axis angle offset

    Creates a virtual line that is at an off-axis angle offset from another line.

    Operand 1
    • Line

    The Off-axis angle offset operator makes a translated copy of the input operand line by calculating the equivalent depth change for a specified change in off beam axis angle. This calculation importantly assumes a vertically oriented echosounder and a flat bottom. The transducer draft only is taken from the specified transducer. If the line is based upon a sounder-detected bottom then the transducer associated with that variable is used (another transducer cannot be selected). The settings for this operator are on the Off-axis angle offset page of the Line Properties dialog box.

    See: About off-axis angle line offsets for more details.
    Smoothing filter

    Creates a virtual line that is the smoothed version of the operand line.

    Operand 1
    • Line

    The settings for this operator are on the Smoothing filter page of the Line Properties dialog box.

    Span gaps

    Creates a virtual line by bridging any gaps from another line. The bridging line segments can be set to a specified line status.

    Operand 1
    • Line

    The settings for this operator are on the Span Gaps page of the Line Properties dialog box.
    Statistical combination

    Creates a virtual line that is a statistical combination of specified input operand lines with ping time stamps specified by Operand 1. Echoview currently supports mean, maximum, minimum and median depth statistics for this operator. Up to six input lines can be specified. This operator is useful for deriving a single bottom line from bottom lines detected at multiple frequencies.

    Operand 1

    Operand 2

    Operand 3
    • Angular position
    • Boolean
    • Color
    • Complex angular position
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Current velocity
    • Linear
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam targets
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex angular position
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Single targets
    • Sv
    • Target length
    • TS
    • Unspecified dB
    • Line

    • Line

     

    The settings for this operator are on the Statistical combination page of the Line Properties dialog box.

    Notes:
    Threshold offset

    Creates a virtual line offset to another line at the threshold of samples in an acoustic variable. Can be used to detect boundaries such as the end of ring down below the water surface, and vegetation layers above a bottom line. For each ping the algorithm traces downwards or upwards from the original line until a threshold value is reached. The time resolution of Operand 1 dictates the time resolution of the Threshold offset line. As a result, it is advised that the time resolution of Operand 1 and Operand 2 match. Otherwise, unwanted line time-mismatch artifacts may occur.

    Operand 1

    Operand 2
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB
    • Line

    The settings for this operator are on the Threshold Offset page of the Line Properties dialog box.

    See also: About the Threshold offset operator.
    Time offset

    Creates a virtual line by applying a specified time offset to the time of the operand line.

    Operand 1
    • Line

    The settings for this operator are on the Time Offset page of the Line Properties dialog box.
    Towed body time offset

    Creates a virtual line for the visualization of a towed body's position using an acoustic variable and a depth line. The time offset is calculated relative to the platform and considers the platform speed, tow point, tow length and tow depth. See also: Synchronizing towed body media data with echograms.

    Operand 1

    Operand 2
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB
    • Line

    The settings for this operator are on the Towed Body Time Offset page of the Line Properties dialog box.
    Trained model bottom exclusion (experimental)

    Creates a virtual line using a trained inference model for excluding the bottom in an acoustic variable. This is an experimental operator that uses machine learning techniques to pick a bottom exclusion line. The model was trained using 38 kHz Simrad ES60 and ES70 data, and results may vary for data collected under different circumstances.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    Settings for this operator may be specified on the Trained Model Bottom Exclusion page of the Line Properties dialog box.

    Notes:

    Surface

    Operator

    Description

    Fixed depth

    Creates a surface with a fixed depth.

    No operands are required.

    The Depth is specified on the Fixed Depth page of the Surface Properties dialog box. Visibility and Notes may also be specified.

    Note: Fixed depth surfaces can't be exported or displayed on scenes.

    Fixed range

    Creates a surface with a fixed range.

    No operands are required.

    The Range is specified on the Fixed Range page of the Surface Properties dialog box. Visibility and Notes may also be specified.

    Note: Fixed range surfaces can't be exported or displayed on scenes.

    Linear offset

    Creates a surface at a fixed distance from an existing surface.

    Operand 1
    • Surface

    The operand and distance are specified on the Surface Properties dialog box.

    Note: Linear Offset surfaces cannot be exported or displayed on scenes.

    Movement

    Operator

    Description

    Distance correction

    This operator is used to correct distance variables. You can specify the settings for distance Offset and Scaling.

    Operand 1
    • Distance

    See also: Distance Correction settings and notes.

    GPS filter

    This operator creates a position variable containing only those GPS fixes from the operand that match the user specified Fix Specification and Fix Retention values.

    Operand 1
    • Position

     

    See also: GPS Filter settings and notes.

    Kalman GPS smoothing filter

    This operator applies a Kalman filter to a position variable to smooth the cruise track.

    Operand 1
    • Position

    See also: Kalman GPS Smoothing Filter settings and notes.
    Ping time difference

    This operator sets each sample of a ping to be the time elapsed from the previous ping to the current ping, in seconds. The samples of the first ping are set to no data. The output data type is linear.

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    Vessel speed at pings

    This operator creates an echogram where the values of all samples within a ping are set to the speed of the vessel at that ping, in nautical miles per hour. Only fixes with a GPS fix status of "good" and pings with "good" position status are used in speed calculations. When no speed is available, the samples of the ping are assigned the special export value of -9999.0

    The operator can be part of a virtual variable chain to filter out data recorded when the vessel isn't moving. An example dataflow may be Raw variable, Vessel speed at pings, Data range bitmap and Mask (set slow pings to No data).

    Operand 1
    • Complex power dB
    • Complex Sv
    • Complex TS
    • Linear
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Power dB
    • Pulse compressed complex power dB
    • Pulse compressed complex Sv
    • Pulse compressed complex TS
    • Sv
    • TS
    • Unspecified dB

    Multibeam

    These operators perform multibeam-specific operations, however, they are not the only operators which accpect multibeam data. Refer to Operators that accept multibeam data.

    Operator

    Description

    Angle select

    This operator selects the beam which overlaps with a specified angle from vertically down, for multibeam data. 'Overlap' is understood as follows: each beam in the flat sector represented by the multibeam echogram has an angle from vertical calculated for the two lines which bound that beam. If the specified angle is between these two angles for a given beam, that beam is selected. Transducer geometry will affect these two angles. Pings will not be included if the specified angle is horizontal or the tilt angle of the ping is different to that of the first ping in the input operand.

    Operand 1
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also Angle Select settings and notes.

    Beam select

    This operator selects the data for a specified beam from a multibeam input operand. Pings will not be included if the specified beam is horizontal or the tilt angle of the ping is different to that of the first ping in the input operand.

    Operand 1
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Beam Select settings and notes.

    Beam closing filter 3x3

    This operator applies a 3x3 closing filter to each ping of multibeam data.

    A closing filter is a dilation followed by an erosion. It smooths the contours of an image, fuses narrow breaks and long thin gulfs, eliminates small holes, and fills gaps in the contours.

    Operand 1
    • Multibeam boolean
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    Notes:

    Beam convolution 3x3

    This operator applies a user-specified 3x3 convolution matrix to samples in each ping of the multibeam data.

    Operand 1
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also Beam Convolution 3x3 settings and notes.

    Beam dilation filter 3x3

    This operator applies a 3x3 dilation filter to each ping of multibeam data.

    Operand 1
    • Multibeam boolean
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    Notes:

    Beam erosion filter 3x3

    This operator applies a 3x3 erosion filter to each ping of multibeam data.

    Operand 1
    • Multibeam boolean
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    Notes:

    Beam median filter 3x3

    This operator applies a 3x3 median filter to each ping of multibeam data.

    Operand 1
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    Notes:

    Beam opening filter 3x3

    This operator applies a 3x3 opening filter to each ping of multibeam data.

    An opening filter is an erosion followed by a dilation. It smooths the contour of an image, breaks narrow joins between larger areas, and eliminates thin protrusions.

    Operand 1
    • Multibeam boolean
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    Notes:

    Beam scan

    This operator builds up a scanned image from a number of pings. It is intended to be used with data from the Kongsberg Mesotech MS1000 echosounder.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Beam Scan settings and notes.

    Beam subset

    This operator creates a variable containing a specified subset of the beams in another variable.

    Operand 1
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Beam Subset settings and notes.

    Bottom Echo Bitmap

    This operator creates a bitmap (multibeam Boolean variable) with a "false" value for each input value that is determined to contain energy from the bottom echo, and a "true" value for all the remaining input samples. "no data" values are always translated to "false".

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Bottom Echo Bitmap settings and notes.

    Bottom Echo Bitmap H-mode - Furuno

    This operator creates a bitmap (multibeam Boolean variable) with a "false" value for each input value that is determined to contain energy from the bottom echo, and a "true" value for all the remaining input samples. "no data" values are always translated to "false".
    Only operands of ping mode 3 (H-mode) from Furuno data files are accepted as input.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Bottom Echo Bitmap H-mode - Furuno settings and notes.
    Combine fans

    This operator combines simultaneous ping fans from two regular-mode multibeam operands (no V-, S-, H-mode). Both operands must be from transducers with identical geometry. Echoview assumes both pings are from the same transducer. All operands must be of the same data type. The variable transducer must not be overridden, or if overridden, must be overridden to the same transducer as Operand 1. The Combine fans operator is licensed under the Advanced Operators module.

    Operand 1

    Operand 2
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Combine Fans settings and further notes and requirements.

    Double threshold

    This operator is a noise removal operator for multibeam data. It applies two thresholds to the data as follows:

    • Values that are equal to or above the upper threshold are unchanged.
    • Values that are equal to or below the lower threshold are set to a specified threshold value.
    • Values that are between the two thresholds and within the specified influence radius from a data point that has been unchanged are unchanged.
    • Values that are between the two thresholds yet outside the specified influence radius are set to a specified threshold value.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Double Threshold settings and notes.

    Kovesi image denoising

    This operator uses Peter Kovesi's wavelet denoising image processing technique to remove unwanted noise in a ping. This operator performs a highly advanced and complex algorithm and as such performance within Echoview may be affected.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Kovesi Image Denoising settings and notes.

    Maximum Intensity

    This operator produces a maximum intensity (single beam) echogram from multibeam data, where each sample (at range R) contains the maximum value of all the corresponding multibeam samples that are at range R.

    The maximum intensity echogram can be evaluated against your target conversion variable to ensure that your multibeam target detection settings correctly identify all targets.

    This variable could also indicate swim shape and tail-beat frequency of targets, which may be used for species identification. This concept is highly developmental, for further information, refer to use of target range extent to identify swim shape. Note, under the Maximum intensity operator range and depth are the same.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    Maximum intensity - matrix

    This operator scans matrix data along the major- or minor-axis, producing multibeam pings where each sample (at range R) contains the maximum value of all corresponding samples that are also at range R along the scanned axis. The ouput variable data types are Multibeam Sv, Multibeam TS or Multibeam unspecified dB, matched to whichever operand is used.

    Operand 1
    • Matrix Sv
    • Matrix TS
    • Matrix unspecified dB

    See also: Maximum Intensity - Matrix settings and notes.

    Mean of n previous pings

    This operator calculates the mean of a specified number of previous pings. The number of pings averaged will range from 1 up to the specified window size.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Mean of N Previous Pings settings and notes.

    Median of N pings

    This operator calculates the median of a specified number of pings. The number of input pings will range from three up to the specified window size. The window includes pings up to and including the current ping.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Median of N Pings settings and notes.

    Minimum of N pings

    This operator calculates the minimum of a specified number of pings. The number of input pings will range from one up to the specified window size. The window includes pings up to and including the current ping.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Minimum of N Pings settings and notes.

    Multibeam background removal

    This operator calculates a statistic from a window of pings around the current ping. This statistic is intended to capture the static background elements present in the data. It then subtracts that statistic from the current ping, leaving the data without the background.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Multibeam Background Removal settings and notes.
    Multibeam roll at transducer

    This operator applies roll from a roll variable to a multibeam variable.

    The roll will be applied as if it occurred at the transducer location, and in the same plane as the beam fan. A positive roll rotates the positive major axis clockwise when viewed in the direction of the positive minor axis (that is from the negative minor axis to the positive minor axis).

    The operator will give useful results only when the following applies:

    • Firstly, the transducer and roll sensor are physically close to the center of motion of the vessel.

    • Secondly, the beam fan is in the athwartship plane.

    Echoview accepts operands of the following data types as input:
     

    Operand 1

    Operand 2
    • Multibeam angular position
    • Multibeam boolean
    • Multibeam color
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Roll

    See: About roll data for further information.

    Multibeam target detection

    This operator generates multibeam targets from multibeam data. Targets are created from groups of adjoining datapoints that are not thresholded. Each resulting target has a range and major-axis angle corresponding to the geometric center of the group.

    Operand 1
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Multibeam Target Detection settings and notes.

    Multibeam target samples bitmap

    This operator creates a Boolean (bitmap) variable which has the same ping geometry as the first operand. Datapoint values will be false when samples on a ping in the first operand do not fall within the target outlines in the corresponding ping of the second operand. See also: Usage notes.

    Operand 1

    Operand 2
    • Multibeam boolean
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Multibeam targets

    This operator is licensed under the Multibeam Fish Tracking module.

    Multibeam target samples bitmap

    This operator creates a Boolean (bitmap) variable which has the same ping geometry as the first operand.

    The datapoint values are false, when samples on a ping in the first operand do not fall within the range of a target of the corresponding ping of the second operand. See also: Usage notes.

    Operand 1

    Operand 2
    • Multibeam boolean
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Multibeam targets

    This operator is licensed under the Multibeam Fish Tracking module.

    Multibeam target overlay

    This operator overlays multibeam targets on multibeam data to display full input data under the targets. Pings are matched via their time stamps.

    Operand 1

    Operand 2
    • Multibeam targets
    • Multibeam magnitude
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    Notes:

    • This operator is designed to be used with virtual variables created with the Multibeam target detection operator.
    • If you want to approximate the visual view from the Sound Metrics viewer with Sound Metrics data in Echoview, use the Type conversion operator with the Sound Metrics unspecified dB frames variable as Operand 1, and select Sv as the Output type setting on the Type Conversion page of Type conversion virtual variable's Properties dialog box. The Type conversion variable will then be available on the Operand 2 list of the Multibeam target overlay variable.
    • The Filter Targets page is used by this operator.
    • The display of multibeam target data from the first operand is affected by the color scheme of the Multibeam target overlay variable. Similarly, the multibeam target overlay Data tab minimum and maximum color display thresholds control the visibility of overlaid targets.
    • Displayed echogram data from the second operand is affected by the settings of the second operand. It may be necessary to adjust the second operand's color display settings to improve the viewing of the specified multibeam data under the multibeam target overlay echogram.

    Sample statistic subtract

    This operator removes noise from the first operand by averaging (in the linear domain) the pings in the second operand and subtracting the results from each ping in the first operand. The resulting virtual variable has the same ping geometry as the first ping in the first operand.

    If a ping in the first operand and the matching ping in the second operand have the same geometry as the first ping, then its representative is populated with the result of subtracting from each sample the mean (in the linear domain) of the corresponding samples in the second operand.

    Pings in operand 1 that do not match the geometry of the first ping are populated with the "no data" value.

    Pings in operand 2 that do not match the geometry of the first ping are ignored.

    Operand 1

    Operand 2
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: Sample Statistic Subtract settings and notes.
    Sector select

    This operator selects a major or minor sector from a ping matrix, corresponding to the given tilt/bearing angle. The ouput variable data type are Multibeam angular position, Multibeam Sv, Multibeam TS or Multibeam unspecified dB, ie., matched to whichever operand is used.

    Operand 1
    • Matrix angular position
    • Matrix Sv
    • Matrix TS
    • Matrix unspecified dB

    See also: Select Sector settings and notes.

    Target conversion

    This operator generates single targets data from a multibeam targets variable. Each resulting single target has a range and major-axis angle corresponding to the range and angle of a multibeam target.

    Operand 1
    • Multibeam targets

    See also: Target Conversion settings and notes.

    XxYxZ convolution

    This operator applies an XxYxZ convolution algorithm to the echogram.

    Operand 1
    • Multibeam magnitude
    • Multibeam phase
    • Multibeam Sv
    • Multibeam TS
    • Multibeam unspecified dB

    See also: XxYxZ convolution settings and notes.

    Single target detection

    See About single target detection for details.

    Operator

    Description

    Single target detection - single beam (method 1)

    This operator detects single targets using the algorithm implemented by Simrad in the EK500 echosounder.

    Operand 1
    • TS

    See also: Single target detection - single beam (method 1) settings and notes.

    Single target detection - single beam (method 2)

    This operator detects single targets using an algorithm based on Echoview Software's understanding of the single target detection algorithm implemented by Simrad in the EK60 echosounder.

    Operand 1
    • TS

    See also: Single target detection - single beam (method 2) settings and notes.

    Single target detection - split beam (method 1)

    This operator detects single targets using a modified version of the single target detection single beam (method 1) algorithm that applies compensation estimates (based on split-beam angle data) to the peak selection criteria.

    Operand 1

    Operand 2
    • TS
    • Angular position
    • Complex angular position
    • Pulse compressed complex angular position

    See also: Single target detection - split beam (method 1) settings and notes.

    Single target detection - split beam (method 2)

    This operator detects single targets using a modified version of the single target detection single beam (method 2) operator that applies compensation estimates (based on split-beam angle data) to the peak selection criteria.

    Operand 1

    Operand 2
    • TS
    • Angular position
    • Complex angular position
    • Pulse compressed complex angular position

    See also: Single target detection - split beam (method 2) settings and notes.

    Single target detection - dual beam (method 1)

    This operator detects single targets using a modified version of the single target detection single beam (method 1) algorithm that applies compensation estimates (based on the difference between a narrow beam and wide beam signal) to the peak selection criteria.

    Operand 1

    Operand 2
    • TS (narrow beam)
    • TS (wide beam)

    See also: Single target detection - dual beam (method 1) settings and notes.

    Single target detection - dual beam (method 2)

    This operator detects single targets using a modified version of the single target detection single beam (method 2) algorithm that applies compensation estimates (based on the difference between a narrow beam and wide beam signal) to the peak selection criteria.

    Operand 1

    Operand 2
    • TS (narrow beam)
    • TS (wide beam)

    See also: Single target detection - dual beam (method 2) settings and notes.

    Single target detection - wideband

    This operator detects single targets for wideband data. It supports both single beam and split-beam data. When operand 2 is Pulse compressed complex angular position the data is assumed to be split beam.

    Operand 1

    Operand 2
    • Pulse compressed complex TS
    • None
    • Pulse compressed complex angular position

    See also Single target detection - wideband settings and notes.
    Single target detection - Furuno FCV-30

    This operator outputs FCV-30 single targets found in processed compensated TS data produced by the Furuno FCV-30 sounder.

    It accepts operands with the following data types:

    Operand 1

    Operand 2
    • TS
    • Angular position

    Note: A proprietary Furuno beam compensation algorithm is available for use with Single target detection - split beam (method 1 and method 2) operators.

    Single target manipulation

    All distance calculations for single target manipulation operators are performed using coordinates that have been adjusted for transducer geometry.

    Warning: When you apply a single target manipulation operator, you must, on the Calibration page of the Variable Properties dialog box for the resulting virtual variable, select the same transducer that was selected for the first operand (input variable). If a different transducer is selected, the results may be misleading.

    Operator

    Description

    Target length calculator

    This operator calculates the length of each target by target strength and per-species coefficients and stores the result in the length field.

    Operand 1
    • Single targets

    see also: Target Length Calculator settings and notes.

    Target length conversion

    This operator creates a Target length variable from a single targets variable. For each single target, the Target Strength is replaced by a Target length value.

    The target length values may be obtained from the:

    Operand 1
    • Single targets

    For more information, refer to:

    Target property threshold

    This operator removes single targets for which the selected target property does not fall within the specified range.

    Operand 1
    • Multibeam targets
    • Single targets

    See also: Target Property Threshold settings and notes.

    TS substitution

    This operator allows the selection of custom CSV fields or other single target values to be substituted into the TS and/or Uncompensated TS values of each target, with optional dB scaling.

    Operand 1
    • Multibeam targets
    • Single targets

    See also: TS Substitution settings and notes.

    ST difference

    This operator returns the single targets in the first variable that are not within a specified distance of any single target in the second variable.

    Operand 1

    Operand 2
    • Single targets
    • Single targets

    See also: ST Difference settings and notes.

    ST intersection

    This operator returns all the single targets in the first variable that are within a specified distance of any target in the second variable.

    Operand 1

    Operand 2
    • Single targets
    • Single targets

    See also: ST Intersection settings and notes.

    ST union

    This operator returns all the single targets in the first variable, plus any single targets in the second variable that are not within a specified distance of any target in the first variable.

    Operand 1

    Operand 2
    • Single targets
    • Single targets

    See also: ST Union settings and notes.

    See also

    About virtual variables
    Creating and deleting virtual variables
    Data Types
    Dataflow window
    About the Dataflow Toolbox
    Variable Properties dialog box
    Using multiple operands
    Operator licensing in Echoview
    Operators that accept multibeam data

    Echoview Help file 15.0.174 for Echoview 15, 02 October 2024

    Copyright © Echoview Software Pty Ltd 2024. All rights reserved. Echoview is a registered trademark of Echoview Software Pty Ltd. Other brands and trademarks are the property of their respective owners.

    Please report any errors or omissions to support@echoview.com.