Type Conversion
This operator converts a variable from one data type to another data type, e.g. Sv to unspecified dB. 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.
You can convert to common output types such as linear, Sv, TS, unspecified dB, and power dB.
Echoview accepts a single operand of the following data types as input:
-
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
-
Target length
-
TS
-
Unspecified dB
Settings
The Type Conversion Variable Properties dialog box pages include (common) Variable Properties pages and these operator pages:
Operands page
Type Conversion page
The Type Conversion page is displayed on the Variable Properties dialog box if the Type Conversion operator or the Sv to TS or TS to Sv operator has been applied to create the selected virtual variable.
|
Setting |
Description |
|
Output type |
Choose a conversion type from the list (e.g., linear, Sv, TS, unspecified dB, power dB). The output virtual variable takes its values from the input operand, and the output data type is the nominated Output type. |
|
Calibration difference offset |
A transducer constant quantity required by the equations used by the TS to Sv or Sv to TS operator. The Calibration difference offset represents the value for (CSv -CTS) and is used when CSv and/or CTS are unavailable from the data or calibration settings. For information on how to estimate this value refer to the Sv to TS algorithm. |
Notes:
- This operator changes the data type only and does not apply any corrections to sample values.
- This operator is not supported for Angular position data types.
- Output type Power (dB) is not listed for multibeam operands. For an existing Type Conversion variable, dragging a multibeam variable to replace an operand outputs a variable of the same data type but sets samples to No data.
- During the type conversion operation, wideband pulse-compressed data uses the uncompressed pulse length because the conversion removes awareness of pulse compression. To correct this, provide a LocalCal EffectivePulseDuration value for the virtual variable; use the same value as
PulseCompressedEffectivePulseDurationin operand 1. - When used with wideband data, the Type Conversion operator honors the selected Output type. In earlier versions, the output type could be forced based on input (e.g., Wideband TS → TS) regardless of the selection. Opening older files may therefore change variable outputs and operator colors.
- The variable name (dynamic naming) reflects the selected Output type (e.g., Type conversion TS). In earlier versions (e.g., 15.1), the name could mismatch the actual output.