scenvelope

Computes continuous envelope values used by scvsmag.

Description

Part of the VS package.

scenvelope is part of a new SeisComp3 implementation of the Virtual Seismologist [1] (VS) Earthquake Early Warning algorithm (Cua, 2005; Cua and Heaton, 2007) released under the SED Public License for SeisComP Contributions [2]. It generates real-time envelope values for horizontal and vertical acceleration, velocity and displacement from raw acceleration and velocity waveforms. It was implemented to handle the waveform pre-processing necessary for the scvsmag module. It provides in effect continuous real-time streams of PGA, PGV and PGD values which could also be used independently of scvsmag.

The processing procedure is as follows:

  1. gain correction
  2. baseline correction
  3. high-pass filter with a corner frequency of 3 s period
  4. integration or differentiation to velocity, acceleration and displacement
  5. computation of the absolute value within 1 s intervals

The resulting envelope values are sent as messages to the messaging system via the “VS” message group. Depending on the number of streams that are processed this can result in a significant number of messages (#streams/s).

In order to save the messages in the database and to provide them to other modules, the messaging system must to be able to handle these messages. Therefore, the plugins dmvs and dmsm must be available to scmaster and the “VS” group must be added.

The plugins can be most easily added through the configuration parameters in global.cfg:

plugins = dmvs, dmsm

Add the “VS” group the the other message groups defined by scmaster in scmaster.cfg:

msgGroups = VS, ...

and let scenvelope send the messages to the “VS” group instead of “AMPLITUDE”. Adjust scenvelope.cfg:

connection.primaryGroup = VS

Note

When changing connection.primaryGroup, the “VS” group must also be added to the subscriptions in scvsmag.

Configuration

etc/defaults/global.cfg
etc/defaults/scenvelope.cfg
etc/global.cfg
etc/scenvelope.cfg
~/.seiscomp3/global.cfg
~/.seiscomp3/scenvelope.cfg

scenvelope inherits global options.

envelope.saturationThreshold

Type: double

Unit: percent

This parameter defines the relative saturation threshold in percent. If the absolute raw amplitude exceeds X% of 2^23 counts, the station will be flagged as clipped. This assumes a 24-bit datalogger. Default is 80.

envelope.baselineCorrectionBuffer

Type: int

Unit: s

This parameter defines the length of the buffer (in seconds) that is used to compute a real-time average for baseline correction. Default is 60.

envelope.useSC3Filter

Type: boolean

This is for internal testing purposes only. true will cause the SeisComp3 filter routines to be used. If false the filter routines from the Earthworm based CISN/ETH implementation of VS will be employed. Default is false.

Note

envelope.streams.* Defines the white- and blacklist of data streams to be used. The rules to decide if a stream is used or not are the following: ** 1. if whitelist is not empty and the stream is not on the whitelist, don’t use it, ok otherwise ** 2. if blacklist is not empty and the stream is on the blacklist, don’t use it, ok otherwise ** Both checks are made and combined with AND. Either whitelist or blacklist contains a list of patterns (wildcard allowed as * and ?), eg GE..*.*, , GE.MORC..BH? Each stream id (NET.STA.LOC.CHA) will* be checked against the defined patterns.

envelope.streams.whitelist

Type: list:string

The stream whitelist

envelope.streams.blacklist

Type: list:string

The stream blacklist

Command-line

Generic

-h, --help

show help message.

-V, --version

show version information

--config-file arg

Use alternative configuration file. When this option is used the loading of all stages is disabled. Only the given configuration file is parsed and used. To use another name for the configuration create a symbolic link of the application or copy it, eg scautopick -> scautopick2.

--plugins arg

Load given plugins.

-D, --daemon

Run as daemon. This means the application will fork itself and doesn’t need to be started with &.

--auto-shutdown arg

Enable/disable self-shutdown because a master module shutdown. This only works when messaging is enabled and the master module sends a shutdown message (enabled with –start-stop-msg for the master module).

--shutdown-master-module arg

Sets the name of the master-module used for auto-shutdown. This is the application name of the module actually started. If symlinks are used then it is the name of the symlinked application.

--shutdown-master-username arg

Sets the name of the master-username of the messaging used for auto-shutdown. If “shutdown-master-module” is given as well this parameter is ignored.

Verbosity

--verbosity arg

Verbosity level [0..4]. 0:quiet, 1:error, 2:warning, 3:info, 4:debug

-v, --v

Increase verbosity level (may be repeated, eg. -vv)

-q, --quiet

Quiet mode: no logging output

--component arg

Limits the logging to a certain component. This option can be given more than once.

-s, --syslog

Use syslog logging back end. The output usually goes to /var/lib/messages.

-l, --lockfile arg

Path to lock file.

--console arg

Send log output to stdout.

--debug

Debug mode: –verbosity=4 –console=1

--log-file arg

Use alternative log file.

Messaging

-u, --user arg

Overrides configuration parameter connection.username.

-H, --host arg

Overrides configuration parameter connection.server.

-t, --timeout arg

Overrides configuration parameter connection.timeout.

-g, --primary-group arg

Overrides configuration parameter connection.primaryGroup.

-S, --subscribe-group arg

A group to subscribe to. This option can be given more than once.

--encoding arg

Overrides configuration parameter connection.encoding.

--start-stop-msg arg

Sets sending of a start- and a stop message.

--test

Test mode, no messages are sent

Database

--db-driver-list

List all supported database drivers.

-d, --database arg

The database connection string, format: service://user:pwd@host/database. “service” is the name of the database driver which can be queried with “–db-driver-list”.

--config-module arg

The configmodule to use.

--inventory-db arg

Load the inventory from the given database or file, format: [service://]location

--db-disable

Do not use the database at all

Offline

--ts arg

Start time of data acquisition time window, requires also –te.

--te arg

End time of data acquisition time window, requires also –ts.