Sonic 2022, Руководство по эксплуатации

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15.10 TruePix™ Data Format
// *** BEGIN TRUEPIX DATA FORMAT 0 ***
// TruePix is like sidescan with 3D relief. Each sonar ping produces a port
// and starboard time-series of data samples at the sonar's sample rate. Each
// sample contains the signal's magnitude (like sidescan) and across-track
// target direction angle (like bathymetry). After collecting many pings of
// data along a survey line, you now have a large array of data points with
// range, direction, and brightness. Apply noise reduction, and render the
// data as a textured 3D surface.
//
// Two data formats are available: D0 provides magnitudes only, D1 provides
// magnitudes and direction angles. The GUI allows the user to choose the
// desired format.
//
// The sonar generates one TruePix data set per ping. Each data set is
// usually split into multiple UDP packets. The D0 or D1 header includes
// FirstSample and Samples values to help you reassemble the full data set.
//
// Someday you may be able to convert the 16-bit magnitude values to
// micropascals by applying a to-be-determined function involving the sample
// number and the MagnitudeScaling[] coefficients, but this conversion is not
// yet supported so these coefficients are zero. You can convert the
// direction angles from 16-bit values to radians by multiplying by
// AngleScalingFactor.
u32 PacketName; // 'TPX0'
u32 PacketSize; // may be zero in UDP, otherwise: [bytes] size of this entire packet
u32 DataStreamID; // reserved for future use
// section H0: header (present only in first packet of each ping)
u16 H0_SectionName; // 'H0'
u16 H0_SectionSize; // [bytes] size of this entire section
u8 H0_ModelNumber[12]; // example "2024", unused chars are nulls
u8 H0_SerialNumber[12]; // example "100017", unused chars are nulls
u32 H0_TimeSeconds; // [seconds] ping time relative to 0000 hours 1-Jan-1970, integer part
u32 H0_TimeNanoseconds; // [nanoseconds] ping time relative to 0000 hours 1-Jan-1970, fraction part
u32 H0_PingNumber; // pings since power-up or reboot
f32 H0_PingPeriod; // [seconds] time between most recent two pings
f32 H0_SoundSpeed; // [meters per second]
f32 H0_Frequency; // [hertz] sonar center frequency
f32 H0_TxPower; // [dB re 1 uPa at 1 meter]
f32 H0_TxPulseWidth; // [seconds]
f32 H0_TxBeamwidthVert; // [radians]
f32 H0_TxBeamwidthHoriz; // [radians]
f32 H0_TxSteeringVert; // [radians]
f32 H0_TxSteeringHoriz; // [radians]
u16 H0_TxMiscInfo; // reserved for future use
s16 Offset; // [hundredths of a dB] transmit voltage offset at time of ping (divide value by 100 to get dB)
f32 H0_RxBandwidth; // [hertz]
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Version 5.0 Rev r002
Date 05-08-2014
Part No. 96000001