Add empty mfcc vectors at end of sample

Could anyone please help me to understand the purpose of adding empty mfcc vectors at end of sample(addZeroMfccWindow) in finishstream.

That’s how the model is trained: https://github.com/mozilla/DeepSpeech/blob/db717d7f7315cc45e80fad55e3597227f47a71a0/training/deepspeech_training/train.py#L57-L74

So the native client is implemented to match it.