Manual

June 2004 Isis® Sonar User's Manual, Volume 2 102
ContactGroundRange
566 FLOAT Ground range to the contact
unassigned[2]
568 CHAR Unused
InternalFileName[248]
816 CHAR Internal use (passing
.CON/.TGT file name from
Target to Isis)
FishPitch
820 FLOAT Pitch in degrees (positive =
nose up)
FishRoll
824 FLOAT Roll in degrees (positive = roll to
stbd)
E.7.3 The Image Structure
Bitmap bits (BitmapWidth • BitmapHeight • BitsPerPixel/8) bytes. Each 8-bit
byte (0…255 for 8-bit data, -32768… +32767 for 16-bit data) is related to
sonar input voltage linearly from 0… +5 volts or –5… +5 volts, respectively.
A zero is always a low return, and the more negative or positive a value
gets, the stronger the acoustic echo.
E.7.4 Telemetry Structure
Target also uses a structure called Telemetry. Shown in Table E-8, the
structure keeps track of the telemetry information for each ping. The number
of pings is equal to the height. The total number of bytes for this entity is
BitmapHeight * sizeof(
telemetry). With this data, Target has detailed
information about every pixel in the image.
Don't change the size of this structure —
or else you won't be able to play back old contacts!
Appendix E: Using the Target Utility