Move tensorflow-gpu to requirements_gpu.txt (#399)

README.md

@@ -40,7 +40,7 @@ You will need the following whether you plan to use the toolbox only or to retra
 
 Run `pip install -r requirements.txt` to install the necessary packages. Additionally you will need [PyTorch](https://pytorch.org/get-started/locally/) (>=1.0.1).
 
-A GPU is mandatory, but you don't necessarily need a high tier GPU if you only want to use the toolbox.
+If you have a GPU, run `pip install -r requirements_gpu.txt` to enable GPU support. A GPU is recommended, but it is not required to use the toolbox.
 
 ### Pretrained models
 Download the latest [here](https://github.com/CorentinJ/Real-Time-Voice-Cloning/wiki/Pretrained-models).

requirements.txt

-# each portion of tensorflow is needed
-# core package is for RNN, cpu and gpu are for specific system speed-ups
 tensorflow==1.15
-tensorflow-cpu==1.15
-tensorflow-gpu==1.15
 umap-learn
 visdom
 librosa>=0.5.1

requirements_gpu.txt

+# This is a list of recommended packages that also enables GPU support.
+# You will also need the packages listed in requirements.txt
+
+tensorflow-gpu==1.15   # Enables GPU support for synthesizer
+webrtcvad              # Better noise reduction when processing audio files