wiki:compress_UA

Version 1 (modified by branden, 9 years ago) (diff)

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Earthworm Module: compress_UA

Contributed by:

Function

The compress_UA and decompress_UA modules implement the gencompress algorithm which is used with permission from Boulder Real Time Technologies, Inc., copyright 1997.

Details

The compress_UA and decompress_UA modules implement the gencompress algorithm which is used with permission from Boulder Real Time Technologies, Inc., copyright 1997.

Compress_UA inputs selected trace data messages (TYPE_TRACEBUF), compresses the samples via the BRTT algorithm, leaves the header intact, and outputs the resulting message as TYPE_TRACE_COMP_UA. Trace messages are selected via SCN names listed in the .d file. Wildcards are allowed. The compressed data output can be tagged with compress_UA's installation_id and module_id (normal Earthworm behavior), or with the installation_id and module_id of the original uncompressed message.

decompress_UA is the matching decompressor. Its output is identical to the input to the compressor. As with compress_UA, decompress_UA's output can be tagged with its own installation_id and module_id, or with those of the original message. This option allows the logo of the original data source to be preserved thru the compress/decompress operation.

In order to run compress_UA and decompress_UA, you must add TYPE_TRACE_COMP_UA message to 'earthworm.d'.

Example Configuration File =

#     compress_UA's Configuration File
#
MyModId       MOD_COMPRESS_UA   # This instance of compress_UA
InRing              WAVE_RING   # Transport ring to find waveform data on,
OutRing             COMP_RING   # Transport ring to write output to,
HeartBeatInterval   15          # Heartbeat interval, in seconds,
LogFile             1           # 0=write log to stderr/stdout, not to disk
                                # 1=write a log file to disk
                                # 2=write a module log but not to stderr/stdout

UseOriginalLogo     0   # 0=use compress_UA's logo on outgoing TYPE_TRACE_COMP_UA msgs
                        # non-zero=use instid & modid of original TYPE_TRACEBUF msg
                        #          on outgoing TYPE_TRACE_COMP_UA msg

# instead of getting specific LOGOS, we are only interested in
# messages of TYPE_TRACEBUF, but we may want to specify messages
# with particular SCN codes of interest
#
# Wildcard character '*' is allowed in the SCN_Code fields
#

#GetEventsFrom  *   *   *       INST_WILDCARD      MOD_WILDCARD
 GetEventsFrom  *   *   NC      INST_WILDCARD      MOD_WILDCARD
 GetEventsFrom  KSP *   *       INST_WILDCARD      MOD_WILDCARD
#GetEventsFrom  KSP *   NC      INST_WILDCARD      MOD_WILDCARD
#GetEventsFrom  KSP VHZ *       INST_WILDCARD      MOD_WILDCARD
#GetEventsFrom  HGS VHZ NC      INST_WILDCARD      MOD_WILDCARD

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