Preface

This guide documents the Waveform Database interface library (the WFDB library), a package of C-callable functions that provide clean and uniform access to digitized, annotated signals stored in a variety of formats. These functions were originally designed for use with databases of electrocardiograms, including the MIT-BIH Arrhythmia Database (MIT DB) and the AHA Database for the Evaluation of Ventricular Arrhythmia Detectors (AHA DB). In February 1990, the predefined annotation set was expanded to accommodate the needs of the European ST-T Database (ESC DB). The WFDB library is sufficiently general, however, to be useful for dealing with any similar collection of digitized signals, which may or may not be annotated. The WFDB library has evolved to support the development of numerous other databases that include signals such as blood pressure, respiration, oxygen saturation, EEG, as well as ECGs. Among these multi-parameter databases are the MIT-BIH Polysomnographic Database, the MGH/Marquette Foundation Waveform Database, and the MIMIC Database. Thus the WFDB library is considerably more than an ECG database interface.

This guide describes how to write C-language programs that use databases of ECGs and other signals. A standard set of such programs is included in the WFDB Software Package, and is described in the WFDB Applications Guide; other documents describe the databases themselves, and existing programs that use them (see section Sources, for information about obtaining these and related items).

There are a few important concepts that should be well understood before going further. These concepts include records; signals, samples, and time; and annotations.

If this is your first exposure to the WFDB library,
study the three nodes above before going on.