contourAreaAsync function
ContourArea calculates a contour area.
For further details, please see: https:///docs.opencv.org/3.3.0/d3/dc0/group__imgproc__shape.html#ga2c759ed9f497d4a618048a2f56dc97f1
Implementation
Future<double> contourAreaAsync(VecPoint contour) async {
final p = calloc<ffi.Double>();
return cvRunAsync0(
(callback) => cimgproc.cv_contourArea(contour.ref, p, callback),
(c) {
final rval = p.value;
calloc.free(p);
return c.complete(rval);
},
);
}