Add --viterbi option to README description

README.md

@@ -49,7 +49,7 @@ The resulting `audio_file.f0.csv` contains 3 columns: the first with timestamps
     0.08,199.678,0.775208
     ...
 
-The script can also optionally save the output activation matrix of the model to an npy file (`--save-activation`), where the matrix dimensions are (n_frames, 360) using a hop size of 10 ms (there are 360 pitch bins covering 20 cents each). The script can also output a plot of the activation matrix (`--save-plot`), saved to `audio_file.activation.png` including an optional visual representation of the model's voicing detection (`--plot-voicing`). Here's an example plot of the activation matrix (without the voicing overlay) for an excerpt of male singing voice:
+By default CREPE does not apply temporal smoothing to the pitch curve, but Viterbi smoothing is supported via the optional `--viterbi` command line argument. The script can also optionally save the output activation matrix of the model to an npy file (`--save-activation`), where the matrix dimensions are (n_frames, 360) using a hop size of 10 ms (there are 360 pitch bins covering 20 cents each). The script can also output a plot of the activation matrix (`--save-plot`), saved to `audio_file.activation.png` including an optional visual representation of the model's voicing detection (`--plot-voicing`). Here's an example plot of the activation matrix (without the voicing overlay) for an excerpt of male singing voice:
 
 ![salience](https://user-images.githubusercontent.com/266841/38465913-6fa085b0-3aef-11e8-9633-bdd59618ea23.png)