Digital persona fingerprint verification takes a lot of time
Remove everything that is repeated in the loop and return/do the same thing. Put them outside the loop. Example, this draw the same image every time, you only need it once.

DrawPicture(ConvertSampleToBitmap(Sample))


And this seems to get the same feature every time.

Dim features As DPFP.FeatureSet = ExtractFeatures(Sample, DPFP.Processing.DataPurpose.Verification)