Phase detection and picking on waveforms.
scautopick applies threshold monitoring by searching for waveform anomalies in form of changes in amplitudes. It is applied for detecting phase arrivals and and for measuring related features and amplitudes. The phase arrivals are typically associated by modules like scautoloc for locating the source.
scautopick detects phase onsets for generating picks. Initally, it searches for detections on the waveform streams defined by global bindings.
A primary detector is applied first. When a detection is found, ‘P’ is by default
assigned to the guess of the phase type (phaseHint). The actual guess can be configured by
phaseHint. By default the primary detector applies a robust STA/LTA
STALTA() filter) to waveforms for making detections. Other
detection filters and filter chains can be choosen from the
list of SeisComP filters. A guess of the pick type may
be defined by
Waveforms are typically pre-filtered before the actual
STALTA() filter. Without further configuration a
running-mean highpass, a cosine taper and a Butterworth bandpass filter of
third order with corner frequencies of 0.7 and 2 Hz are applied before the
STALTA() filter. The entire filter sequence is configurable by
filter, module configuration, or
Once the STA/LTA ratio has reached a configurable threshold (by default 3) for a particular stream, a pick is set to the time when this threshold is exceeded (pick time) and the picker is set inactive. The picker is reactivated for this stream once the STA/LTA ratio falls to the value of 1.5 (default).
The trigger thresholds are configurable:
Initial detections can be further adjusted by a second-stage phase re-picker
(post picker) as defined by
picker. The re-picker should be tuned
carefully and global bindings parameters
picker.* should be
After having detected a phase, the re-picker will be inactive and accept no further detection until
The amplitudes measured after filtering (
filterin module configuration or
detecFilterin binding configuration) fall below the
thresholds.triggerOff(module configuration) or
trigOff(binding configuration) and
if . Otherwise:
Based on the inital detection or pick a secondary picker may applied be applied,
e.g., for picking S phases as defined by
spicker. The secondary picker
is halted as soon as new detections are made unless
As for the re-picker also the spicker should be tuned carefully and global
spicker.* should be set.
global bindings parameters
For extracting features related to picks such as polarization parameters
fx and the related global bindings parameters
The second task of scautopick is to calculate amplitudes of a given type for the corresponding magnitude type (see scamp for a list of amplitude types and scmag for the magnitude types). Such amplitudes are required by:
scautoloc for associating phase picks and generating a source location
EEW (earthquake early warning) systems in order to provide raüid amplitudes for magnitudes as soon as source locations are available.
The time window for measuring amplitudes starts at the pick time. The window
length is constant and specific to the amplitude type. It can be adjusted in
global bindings. For example mb is calculated
for a fixed time window of 30 s after the pick, mB for time window of 60s, for
MLv a time window of 150 s is estimated to make sure that S-arrivals are inside
this time window. The pre-calculated amplitudes are sent out and received by
the magnitude tool, scmag.
The fixed time window poses a limitation to EEW system. Howver, a speed-up is
Read the scamp documentation for more details on amplitude measurements.
Modes of Operation¶
scautopick usually runs in the background connected to a real-time data source such as Seedlink. This is referred to as online mode. Another option to run scautopick is on offline mode with files.
In real-time mode the workflow draws like this:
scautopick reads all of its binding parameters and subscribes to stations defined by global binding parameters where
detecEnableis set to
Each incoming record is filtered according to
sendDetectionsis set to
true, a trigger will be sent in any case for e.g. debugging.
After the primary stage has finished (detector only or picker) secondary pickers will be launched if configured with
These steps repeat for any incoming record.
To run scautopick in the background as a daemon module enable and start it
$ seiscomp enable scautopick $ seiscomp start scautopick
For executing on the command line simply call it with appropriate options, e.g.
$ seiscomp exec scautopick -h
Due to code changes in the file data source, the command line option –playback is essential for non-real-time operation. Otherwise a real-time time window is set and all records are most likely filtered out.
To tune scautopick or to do playbacks it is helpful to run scautopick not with
a real-time data source but on a defined data set, e.g. a multiplexed sorted miniSEED
volume. scautopick will apply the same workflow as in online mode but the
acquisition of data records has to change. If the input data (file) has been
read, scautopick will exit and furthermore it must not ask for a particular
time window, especially not for a real-time time window. To accomplish that
the command-line parameter
`--playback` has to be used. Example:
$ scautopick --playback -I data.mseed
This call will process all records in
data.mseed for which bindings
exist and send the results to the messaging. If all data records are processed,
scautopick will exit. The processing steps are similar to the online mode.
`--ep` for offline processing without messaging. The results are
printed in SCML format. Example:
$ scautopick --playback -I data.mseed --ep -d [type]://[host]/[database] > picks.xml
scautopick inherits global options.
Defined the record ringbuffer size in seconds.
The leadTime defines the time in seconds to start picking on waveforms before current time.
If enabled, picks can be made on waveforms which are older than current time - "leadTime". Current time is the time when the module was started. This allows to pick historic data in real-time playbacks which are preserving the record times. See e.g. the "msrtsimul" module. This option deactivates "leadTime". Activate only for playbacks.
The initTime defines a time span in seconds for that the picker is blind after initialization. This time is needed to initialize the filter and depends on it.
Interpolate gaps linearly? This is valid for gaps shorter than thresholds.maxGapLength.
If enabled, all streams that are received by the picker are used for picking. This option has only effect if a file is used as input which contains more data than the picker requests. If connected to a waveform server such as SeedLink, the picker will only receive the data it is subscribed to.
The default filter used for making detections. Station-specific configurations (bindings) override this value.
The time correction applied for a pick. Station-specific values (bindings) override this value.
The re-picker to use. By default only simple detections are emitted as picks. To enable re-picking on a time window around the detection, an algorithm (plugin) can be defined with this parameter.
Currently available: "AIC", "BK" or "GFZ".
More options may be available by plugins. Configure related parameters in global bindings.
Phase hint to be assigned to the pick made by the primary picker.
If enabled and "picker" is configured, then initial detections are sent as well. To distinguish between detections and picks the evaluation status of the pick is set to "rejected". This is meant to be a debug option which can be used to compare detections and picks by their evaluation status.
The secondary picker to use, e.g., for picking S-phases. Currently available is: "S-L2". More options may be available by plugins. Configure related parameters in global bindings.
If enabled, all secondary pickers that were triggered by a previous pick will be terminated when a new detection or pick has been found. This aims to avoid the case where an S phase is wrongly picked as P but would also be picked as S by the secondary picker. But suppressing the S pick can lead to undesired results. It might be better in some situations to have two picks (P and S) instead only a wrong P.
If enabled and "picker" or "spicker" is configured, extra comments will be added to the resulting pick.
SNR: added if SNR >= 0, comment id is "SNR"
Configures the feature extraction type to use. Currently available: "DFX". Configure related parameters in global bindings.
When configured, the usability of the features for locating depends on the used locator, e.g. LOCSAT. Read the locator’s documentation and configuration parameters.
MLv, mb, mB
The amplitude types to be computed by the picker based on picks.
thresholds.* Threshold parameters for the primary picker.
For which value on the filtered waveforms is a pick detected. Station specific values override this value.
The value the filtered waveforms must reach to enable detection again. Between triggerOn and triggerOff the picker is blind and does not produce picks. Station specific values override this value.
The maximum gap length in seconds to handle. Gaps larger than this will cause the picker to be reset.
The time window used to compute a maximum (snr) amplitude on the filtered waveforms.
The time used together with measured amplitude and thresholds.minAmplOffset for scaling the amplitude below which the picker is inactive after a P pick. Read the documentation!
The amplitude used together with measured amplitude and thresholds.deadTime for scaling the amplitude below which the picker is inactive after a P pick. The value is typically similar to the trigger threshold. Read the documentation!
Configure a list of magnitude types. Update and send amplitudes for these magnitudes as soon as data are available. Do not wait for complete time windows. Only magnitudes computed by scautopick as given by the amplitudes parameter are considered. This option is for rapid magnitude estimation and EEW.
WARNING: This option increases the load on the system!
Message group for sending amplitudes to.
Enables/disables picking on a station.
Defines the filter to be used for picking.
For which value on the filtered waveform is a pick detected.
The value the filtered waveform must reach to enable a detection again.
The time correction applied to a pick.
Defines whether the detector applies sensitivity correction (applying the gain) or not in advance to filter the data.
- -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. Example: 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¶
Set 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¶
Set 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 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¶
Limit the logging to a certain component. This option can be given more than once.
- -s, --syslog¶
Use syslog logging backend. The output usually goes to /var/lib/messages.
- -l, --lockfile arg¶
Path to lock file.
- --console arg¶
Send log output to stdout.
Execute in debug mode. Equivalent to --verbosity=4 --console=1 .
- --log-file arg¶
Use alternative log file.
- -S, --subscribe-group arg¶
A group to subscribe to. This option can be given more than once.
- --start-stop-msg arg¶
Set sending of a start and a stop message.
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 config module to use.
- --inventory-db arg¶
Load the inventory from the given database or file, format: [service://]location .
Do not use the database at all
List all supported record stream drivers.
- -I, --record-url arg¶
The recordstream source URL, format: [service://]location[#type]. "service" is the name of the recordstream driver which can be queried with "--record-driver-list". If "service" is not given, "file://" is used.
- --record-file arg¶
Specify a file as record source.
- --record-type arg¶
Specify a type for the records being read.
Do not connect to a messaging server and do not use the database.
Switches to playback mode which does not request a particular time window from the input data source. This implies that all records are forwarded to scautopick if files are being used. Without this option scautopick sets the requested start time to NOW-leadTime and therefore would not work anymore with older datasets in offline mode or when running playbacks.
Outputs an XML event parameters file containing all picks and amplitudes. This option implies offline.
- --amplitudes arg¶
Enables or disables computation of amplitudes.
Runs the picker as usual but does not send any messages. This can be useful to test the picker within a running system.
Dumps the current configuration and exits. Station configuration is only read if the picker connects to the messaging and the database. In offline mode it will only dump the application specific setting unless a station.conf file is provided.