absDiffAsync function
AbsDiff calculates the per-element absolute difference between two arrays or between an array and a scalar.
For further details, please see: https://docs.opencv.org/master/d2/de8/group__core__array.html#ga6fef31bc8c4071cbc114a758a2b79c14
Implementation
Future<Mat> absDiffAsync(Mat src1, Mat src2) async => cvRunAsync(
(callback) => cffi.core_AbsDiff_Async(src1.ref, src2.ref, callback),
matCompleter,
);