|[ < ]||[ > ]||[ << ]||[ Up ]||[ >> ]||[Top]||[Contents]||[Index]||[ ? ]|
The annot argument of
putann is an
object of type
WFDB_Annotation containing these fields:
time of the annotation, in samples from the beginning of the record. The times of beat annotations in the ‘atr’ files for the MIT DB generally coincide with the R-wave peak in signal 0; for the AHA DB, they generally coincide with the PQ-junction.
annotation code; an integer between 1 and
See section Annotation Codes, for a list of legal annotation codes.
ACMAX is defined in ‘<wfdb/ecgcodes.h>’.
signed char subtyp
unsigned char chan
signed char num
and 127. In MIT DB ‘atr’ files, the
subtyp field is used with noise and artifact annotations to
indicate which signals are affected (see section Annotation Codes).
chan field is intended to indicate the signal to which the
annotation is attached. More than one annotation may be written with
time if the
chan fields are distinct and in
ascending order. The semantics of the
chan field are
unspecified, however; users may assign any desired meaning, which need
not have anything to do with signal numbers. In user-created annotation
files, these fields can be used to store arbitrary small integers. The
subtyp field requires no space in a standard annotation file
unless it is non-zero; the
num fields require no
space unless they have changed since the previous annotation.
a free text string. The first byte is interpreted as an
char that specifies the number of bytes that follow (up to 255). In
MIT DB ‘atr’ files, the
aux field is used with rhythm
change annotations to specify the new rhythm, and with comment
annotations to store the text of the comment
(see section Annotation Codes).
The string can contain arbitrary binary
data, including embedded nulls. It is unwise to store anything but ASCII
strings, however, if the annotation file may be transported to a system with
a different architecture (e.g., on which multiple-byte quantities may have
different sizes or byte layouts). The
aux field requires no
space in a standard annotation file if it is
NULL. Note that
conversion of annotation files to other formats may entail truncation or
loss of the
aux string. Note also that the
getann points to a small static buffer (separately
allocated for each input annotator beginning with WFDB library version
9.4) that may be overwritten by subsequent calls.
See section Example 3: An Annotation Printer, for a short program that examines the contents of a
|[ < ]||[ > ]||[ << ]||[ Up ]||[ >> ]|
George B. Moody (email@example.com)