flipAsync function
Flip flips a 2D array around horizontal(0), vertical(1), or both axes(-1).
For further details, please see: https://docs.opencv.org/master/d2/de8/group__core__array.html#gaca7be533e3dac7feb70fc60635adf441
Implementation
Future<Mat> flipAsync(InputArray src, int flipCode) async =>
cvRunAsync((callback) => cffi.core_Flip_Async(src.ref, flipCode, callback), matCompleter);