SeedLink Monitor - QuickStart

Anthony Lomax

Anthony Lomax Scientific Software
Mouans-Sartoux, France

SeisGram2K Seedlink Monitor


Introduction, Copyright notice
QuickStart configuration
Usage Hints
SeisGram2K SeedLink-specific Command Arguments
Ideas for future development


This page gives instructions for downloading the SeisGram2K Seismogram Viewer and running it in SeedLink Monitor mode (see screen image). 

In SeedLink Monitor mode SeisGram2K connects to one or more SeedLink servers, requests one or more data streams, and appends and displays new data packets as they are received in near-realtime.  A status panel to the left of each trace group show the data (Lf) and feed (Lf) latency with configurable colors for differnt latency time limits.

SeedLink is a part of the SeisComP package; for more information see What is SeisComP?.

SeisGram2K SeedLink Monitor mode and associated softwaare development is supported by:
        MEREDIAN - European Union Project (EVR1-CT-2000-4007)
For an overview of available Java SeedLink software, see: MEREDIAN - Java SeedLink development

WARNING: Parts of this software are new and have not yet been reviewed or thoroughly tested - IT IS IMPORTANT THAT YOU VERIFY THE CORRECT FUNCTIONING OF THE SOFTWARE FOR YOUR PURPOSES.
  If you have problems or suggestions, please contact Anthony Lomax; please specify the type and version of your computer hardware, operating system and Java installation, and provide the complete output of SeisGram2K from your console or command window.

Copyright notice:

The SeisGram2K Seismogram Viewer program and source code are distributed under the terms of the GNU General Public License (GNU GPL): GNU General Public License and translations (Or a local copy of the GNU General Public License)

QuickStart configuration

Download SeisGram2K Seismogram Viewer and run it in SeedLink Monitor mode by following the steps below:

  1. You must have Java SDK 2 or JRE 2 or higher installed:
  2. You can check for the presence and version of Java on your system with the command:

    java -version

    If you do not have a recent version of Java available on your system (JRE (Java Runtime Environment - for end users), or Java SDK (Java Software Development Kit - for developers)), you can download Java from Sun for LINUX, Solaris, Macintosh and Windows.

    If not done automaticlly at installation, remember to update the path environment variable (UNIX) or the PATH variable (Windows) if you want to be able to run the Java executables (java, jar, etc.) from any directory without having to type the full path of the command. See the Java installation documentation for more details.

  3. Download the SeisGram2K jar achive file:
  4. Create a directory for the SeisGram2K jar file, i.e.


    Download the following file to this directory (To download from a browser directly to local disk, press the right mouse button over each link and select "Save Link As..." (Netscape/Mozilla) or "Save Target As..." (IE)):

    SeisGram2K51.jar - SeisGram2K class files (the Java "byte-code" for SeisGram2K - DO NOT UNPACK THIS FILE)) - (Most recent beta release)

  5. Run SeisGram2K in SeedLink Monitor mode to view near-realtime data

    To view all components at 2 GEOFON stations, alligned in time from realtime-1200s to realtime, with all channels in separate windows, enter:

    java -cp my_java_dir/SeisGram2K51.jar net.alomax.seisgram2k.SeisGram2K  -seedlink ",GE_APE:BH?#1200" -seedlink.groupchannels NO

To view as above, with the peak-to-peak amplitudes fixed at 25000 counts, data from now-windowLength to now read to back fill the view window, channels from each station grouped into single windows, the means removed, and the realtime update set to 5 sec interval, enter:

java -cp my_java_dir/SeisGram2K51.jar net.alomax.seisgram2k.SeisGram2K  -seedlink ",GE_APE:BH?#1200#25000#25000" -seedlink.groupchannels YES -commands.onread rmean -realtime.update 5.0  -seedlink.backfill=YES

To view a large selection of stations from GEOFON  and IRIS, enter:

java -cp my_java_dir/SeisGram2K51.jar net.alomax.seisgram2k.SeisGram2K  -seedlink " LH?,GE_APE:BH?#1200; LH?,US_CMB:BH?#1200" -seedlink.groupchannels YES -commands.onread rmean

If you use a proxy or firewall, or if you get the message: Connection timed out: connect
see Running Java with a proxy or firewall.

Usage hints

  1. To analyse and process a trace group without it being automatically updated, resized and scrolled: Open the trace in a new SeisGram2K window by selecting the group and then pressing the button SG2K on the upper right of the program window.
  2. To adjust the time window to show all data in memory: On the menu bar, select View -> AllignTo.. -> GlobalMin-Max
  3. To return to default realtime window: On the menu bar, select View -> AllignTo.. -> Realtime-Ns - Realtime
  4. To display a stream with its mean removed : Add the command argument: -commands.onread=rmean (useful when displaying multiple components in single group window with -seedlink.groupchannels=YES)
New!QuakeExplorer now supports viewing parameteric information and displaying near-realtime streams from a SeedLink server. See QuakeExplorer

SeisGram2K SeedLink-specific Command Arguments

A subset of the SeisGram2K command arguments that are useful with the SeedLink Monitor mode:

Usage: java [-cp <classpath>] net.alomax.seisgram2k.SeisGram2K [-help] [[-<parameter>=<value>]...]

      -help  prints the usage and argument list

   argument pairs (* indicates defaults):

      -display.allign=<Group window allignment at startup (NONE* || ACTIVE || GLOBAL || START || OTIME || LAST_DATA || REALTIME)>
      -display.analysistoolbar=<Show analysis toolbar at startup (YES* | NO)>
      -display.beep.error=<Sound system beep for errors (ON* | OFF)>
      -display.beep.warning=<Sound system beep for warnings (ON | OFF*)>
      -display.font=<Font for trace group display window (<size factor>, BOLD | ITALIC | PLAIN*)><Draw selection panel to the right of each group (YES* | NO)><Draw separator lines between groups (YES* | NO)>
      -display.lockallignment=<Lock group windows to common time base at startup (YES | NO*; YES* with seedlink)>
      -display.maxvisible=<Maximum number of groups to display without scrolling (6*)>
      -display.messagewindow=<Show messagewindow at startup (YES* | NO)>
      -display.monitor=<Monitor mode display (YES | NO*, <number of trace rows per group>, <auto full window delay (sec))>
      -display.viewingtoolbar=<Show viewing toolbar at startup (YES* | NO)>
      -realtime.update=<Realtime scrolling update interval in seconds (1.0*)>
      -seedlink=<SeedLink Aquisition   
where stream is in NET_STA format, for example: IU_KONO:BHE BHN,GE_WLF,MN_AQU:HH?.D (use quotes "..." around whole parameter value when blanks are present),
minPeakToPeakAmplitude / maxPeakToPeakAmplitude set hard limits for the minimum / maximum display amplitudes so that background noise does not fill the group windows / large peaks or spikes do not cause the signal to be a flat line
title text displayed at the upper right of each group window
multiplier is a constant value to be multiplied into the amplitude values of each stream on read, allows crude correction for channel gain and transfer function
      -seedlink.backfill=<read data from now-windowLength to now to back fill view window with data (YES | NO*)>
      -seedlink.clocktype=<Time source for estimating realtime base (SEEDLINK_INFO* | SYSTEM)>
with SEEDLINK_INFO the timestamp in the SeedLink INFO packets is used to determine realtime,
with SYSTEM the local system clock is used to determine realtime, 
      -seedlink.groupchannels=<SeedLink channel group mode (YES* | NO)>
      -seedlink.status.latency.limits=<Comma separated list of max latency times in sec for green->red panel color (t1,t2,...)>
default: 10.0,60.0,600.0,3600.0,21600.0,86400.0<Show SeedLink status panel (YES* | NO)>
      -title=<Window title>

For a complete list of command arguments, see the Help->Help->Running,arguments menu in SeisGram2K.

Ideas for future development

Below is a list of ideas for future development of the SeisGram2K SeedLink Monitor.  If you have suggestions or requests for  additional functionality, or would like to affirm your interest in some of the items below, please e-mail to Anthony Lomax.  The incorporation into SeisGram2K of these items will depend on level of interest, available funding and time constraints.

Idea for future development
1. Add parameters to set a minimum amplitude to prevent noise level signal from filling the display window, and a maximum amplitude to prevent anomalous peaks from hiding the background signal. Done!
2. Add support for reading SeedLink detection records and plotting the detection times on the traces.
3. Add a configurable alarm system for detections, low or high aveage signal, large latency times, etc.
4. Add support for a default STA/LTA detector and for user provided detector algorithms.

Questions? Comments? Suggestions? Please e-mail to Anthony Lomax.

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SeisGram2K SeedLink Monitor