Introduction to SEMIA, Version 3.0.1

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SEMIA, version 3.0.1, is a tool for viewing time series of diagnostic and morphology parameters of long-term ambulatory recordings, and ST segment annotations with their corresponding ECG waveforms of the Long-Term ST Database (LTST DB). SEMIA was created during the development of the LTST DB, a project supported by Medtronic, Inc. (Minneapolis, MN, USA) and Zymed, Inc. (Camarillo, CA, USA).

Compiling SEMIA

If you have not already installed the WFDB software package and the XView toolkit, do so now.

If you are running under GNU/Linux, you may not need to compile SEMIA. Try running the precompiled version of SEMIA available here. (You will still need to have installed WFDB and XView in order to do this successfully.)

If you need to compile SEMIA, make a directory for the SEMIA sources, then copy all files from this directory into it. (For convenience, you may download this gzip-compressed tar archive of all files in this directory rather than downloading the individual files.)

Enter your directory of SEMIA sources and type 'make'.

You may encounter many warnings related to improperly formatted comments in XView #include files. These warnings may be ignored. If you wish to eliminate them, download and apply this patch (read and follow the instructions at the beginning of the patch to see how to apply it).

When 'make' finishes, copy semia into a directory in your PATH, and copy semia.opt and semia.hlp into the directory where you wish to use SEMIA.


To run SEMIA successfully, the following files of the LTST DB are needed in the current working directory:

The last three of these files are contained within the files in the LTST DB directory on PhysioNet (or on the "Subset" CD-ROM). Download the file and unpack it using a command such as:


In addition, you will need copies of semia.opt (a text file containing SEMIA's options) and semia.hlp (a text file containing on-line help for SEMIA) in the current working directory, as noted above.

Run SEMIA by typing "semia". Click on the "Help" button to view SEMIA's on-line manual. To open a record, click on "Open", then enter the record name (snnnnn only; do not include .hea or any other suffix in the record name). Depending on the speed of your system, it may take up to a minute for SEMIA to load the data after you click "OK".

Once the data have been loaded, several buttons that were initially inactive become available for use. Each of them ( "Lead0", "Lead1", "Lead2", "Data", and "KL") opens a window when clicked. ("Lead2" remains inactive unless you have opened a record with 3 ECG signals.)


  1. Franc Jager, George B. Moody, Alessandro Taddei, Gorazd Antolic, Michele Emdin, Ales Smrdel, Boris Glavic, Carlo Marchesi, and Roger G. Mark. A Long-Term ST Database for Development and Evaluation of Ischemia Detectors. Computers in Cardiology 1998, pp. 301-304, IEEE Press. ISSN 0276-6547.
  2. Franc Jager, Alessandro Taddei, Michele Emdin, Gorazd Antolic, Roman Dorn, George B. Moody, Boris Glavic, Ales Smrdel, M Varanini, Mitja Zabukovec, Simone Bordigiago, Carlo Marchesi, and Roger G. Mark. The Long-Term ST Database: A Research Resource for Algorithm Development and Physiologic Studies of Transient Myocardial Ischemia. Computers in Cardiology 2000, pp. 841-844. IEEE Press. ISSN 0276-6547.
Icon  Name                         Last modified      Size  Description
[DIR] Parent Directory - [TXT] COPYING 11-Mar-2003 12:29 18K [TXT] Makefile 02-Aug-2002 19:55 475 'make' description file [   ] semia 02-Aug-2002 04:57 250K SEMIA, precompiled for x86/Linux [TXT] semia.hlp 11-Mar-2003 12:29 16K How to use SEMIA [TXT] semia.opt 11-May-2002 13:07 81 configuration file [TXT] 11-Mar-2003 12:29 334K C++ source file [TXT] 11-Mar-2003 12:29 65K C++ source file [TXT] semia_ui.h 11-Mar-2003 12:29 9.8K C++ include file

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Updated Friday, 28-Oct-2016 22:58:42 CEST

PhysioNet is supported by the National Institute of General Medical Sciences (NIGMS) and the National Institute of Biomedical Imaging and Bioengineering (NIBIB) under NIH grant number 2R01GM104987-09.