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wabp - arterial blood pressure (ABP) pulse detector


wabp -r record [ options ... ]


wabp attempts to locate arterial blood pressure (ABP) pulse waveforms in a continuous ABP signal in the specified record. The detector algorithm is based on analysis of the first derivative of the ABP waveform. The output of wabp is an annotation file (with annotator name wabp) in which all detected beats are labelled normal.

wabp can process records containing any number of signals, but it uses only one signal for ABP pulse detection (by default, the lowest-numbered ABP, ART, or BP signal; this can be changed using the -s option, see below). wabp is optimized for use with adult human ABPs. It has been designed and tested to work best on signals sampled at 125 Hz. For other ABPs, it may be necessary to experiment with the sampling frequency as recorded in the input record’s header file (see header(5) ).

wabp optionally uses the WFDB library’s setifreq function to resample the input signal at 125 Hz.

Options include:

Dump the raw and pre-processed input samples in text format on the standard output, but do not detect or annotate ABP pulses.
-f time
Begin at the specified time in record (default: the beginning of record).
Print a brief usage summary.
Read the signal files in high-resolution mode (default: standard mode). These modes are identical for ordinary records. For multifrequency records, the standard decimation of oversampled signals to the frame rate is suppressed in high-resolution mode (rather, all other signals are resampled at the highest sampling frequency).
Resample the input at 125 Hz (default: do not resample).
-s signal
Specify the signal (number or name) to be used for ABP pulse detection (default: the lowest-numbered ABP, ART, or BP signal).
-t time
Process until the specified time in record (default: the end of the record).
Verbose mode: print information about the detector parameters.


It may be necessary to set and export the shell variable WFDB (see setwfdb(1) ).


To mark ABP pulses in record slp60 of the slpdb database, beginning 5 minutes from the start, ending 10 minutes and 35 seconds from the start, and using signal 1, use the command:
   wabp -r slpdb/slp60 -f 5:0 -t 10:35 -s 1

The output annotations may be read using (for example):
   rdann -r slpdb/slp60 -a wabp

See Also

bxb(1) , ecgpuwave(1) , rdann(1) , setwfdb(1) , sqrs(1) , wqrs(1)

Zong W, Heldt T, Moody GB, and Mark RG. An open-source algorithm to detect onset of arterial blood pressure pulses. Computers in Cardiology 30:259-262 (2003).


Wei Zong ( and George B. Moody (


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Updated 8 March 2019