setPreferableBackend method
SetPreferableBackend ask network to use specific computation backend.
For further details, please see: https://docs.opencv.org/3.4/db/d30/classcv_1_1dnn_1_1Net.html#a7f767df11386d39374db49cd8df8f59e
Implementation
void setPreferableBackend(int backendId) =>
cvRun(() => cdnn.cv_dnn_Net_setPreferableBackend(ref, backendId));