Ubuntu Manpage: gpsdecode - decode GPS, RTCM or AIS streams into a readable format

Provided by: gpsd-clients_3.22-4ubuntu2_amd64

NAME

       gpsdecode - decode GPS, RTCM or AIS streams into a readable format

SYNOPSIS

       gpsdecode [-?] [--ais] [--decode] [--debug LVL] [--encode] [--help] [--json] [--minlength]
                 [--nmea] [--split24] [--types typelist] [--unscaled] [--verbose] [--version]
                 [-c] [-d] [-D LVL] [-e] [-h] [-j] [-m] [-n] [-s] [-t typelist] [-u] [-v] [-V]

DESCRIPTION

       This tool is a batch-mode decoder for NMEA and various binary packet formats associated
       with GPS, AIS, and differential-correction services. It produces a JSON dump on standard
       output from binary on standard input. The JSON is the same format documented in gpsd(8);
       this tool uses the same decoding logic as gpsd, but with a simpler interface intended for
       batch processing of data files.

       All sensor-input formats known to the GPSD project can be decoded by this tool. These
       include: NMEA, AIVDM (the NMEA-derived sentence format used by AIS, the marine Automatic
       Identification System), RTCM2, and all supported GPS binary formats (notably including
       SiRF). See gpsd(8) for applicable standards and known limitations of the decoding logic.

       You can use this tool with nc(1) to examine AIS feeds from AIS pooling services, RTCM
       feeds from RTCM receivers or NTRIP broadcasters.

OPTIONS

-?, -h, --help
Output a usage mssage, then exit.

-c, --json
Sets the AIS dump format to separate fields with an ASCII pipe symbol. Fields are
dumped in the order they occur in the AIS packet. Numerics are not scaled (-u is
forced). Strings are unpacked from six-bit to full ASCII

-d, --decode
Decode packets presented on standard input to standard output. This is the default
behavior.

-D LVL, --debug LVL
Set the debug verbosity level to LVL. It is mainly of interest to for troubleshooting.

-e, --encode
Encode JSON on standard input to JSON on standard output. This option is only useful
for regression-testing of the JSON dumping and parsing code.

-j, --json
Sets the output dump format to JSON (the default behavior).

-m, --minlength
Dump minimum lengths for each packet type in the input (ignoring comment packets).
This is probably of interest only to GSD developers.

-n, --nmea
Dump the generated pseudo-NME0183.

-s, --split24
Report AIS Type 24 sentence halves separately rather than attempting to aggregate
them.

-t TYPES, --types TYPES
A comma-separated list of numeric types. Packets with a numeric AIS, RTCM2, or RTCM3
type are passed through and output only if they match a type in the list. Packets of
other kinds (in particular GPS packets) are passed through unconditionally.

-u, --unsscaled
Suppress scaling of AIS data to float quantities and text expansion of numeric codes.
A dump with this option is lossless.

-v, --verbose
Dump textual packets to output as they are received on input, immediately preceding
corresponding output.

-V, --version
Print version number, then exit.

AIS DSV FORMAT

       With the -c, --ais option, dump lines are values of AIS payload fields, pipe-separated, in
       the order that they occur in the payload. Spans of fields expressing a date are emitted as
       an ISO8601 timestamp (look for colons and the trailing Z indicating Zulu/UTC time), and
       the 19-bit group of TDMA status fields found at the end of message types 1-4 are are
       dumped as a single unsigned integer (in hex preceded by "0x"). Unused regional-authority
       fields are also dumped (in hex preceded by "0x"). Variable-length binary fields are dumped
       as an integer bit length, followed by a colon, followed by a hex dump.

AUTHOR