Fix Deprecation/Future Warnings in Notebook 211-Speech-to-Text (openv…

…inotoolkit#594)

* Fix deprecation/future warnings in notebook 211

- [`waveplot` is deprecated in favor of `waveshow` since librosa v0.9.](https://librosa.org/doc/latest/changelog.html?highlight=waveplot#v0-8-1)

  Note that `max_sr` in [`waveplot`](http://librosa.org/doc/0.8.1/generated/librosa.display.waveplot.html?highlight=max_sr#librosa.display.waveplot) is removed. `max_sr` controls how signals are down-sampled if they’re too long. (`waveplot` uses “a downsampled amplitude envelope” instead)

- `librosa.filters.mel` in `audio_to_mel`

  FutureWarning: Pass `sr=16000, n_fft=512` as keyword args. From version 0.10 passing these as positional arguments will result in an error.

* Fix `waveshow` Speech to text notebook 211

`max_points` should be an `int`, not `float`.

* add librosa to requirements

* Update .docker/Pipfile

* Update requirements.txt

Co-authored-by: Adrian Boguszewski <[email protected]>

notebooks/211-speech-to-text/211-speech-to-text.ipynb

@@ -229,7 +229,7 @@
    "outputs": [],
    "source": [
     "plt.figure()\n",
-    "librosa.display.waveplot(y=audio, sr=sampling_rate, max_points=50000.0, x_axis='time', offset=0.0, max_sr=1000);\n",
+    "librosa.display.waveshow(y=audio, sr=sampling_rate, max_points=50000, x_axis='time', offset=0.0);\n",
     "plt.show()\n",
     "specto_audio = librosa.stft(audio)\n",
     "specto_audio = librosa.amplitude_to_db(np.abs(specto_audio), ref=np.max)\n",
@@ -288,7 +288,7 @@
     "                  win_length=win_length, center=True, window=scipy.signal.windows.hann(win_length), pad_mode='reflect'))\n",
     "\n",
     "    # Create mel filter-bank, produce transformation matrix to project current values onto Mel-frequency bins.\n",
-    "    mel_basis = librosa.filters.mel(sampling_rate, 512, n_mels=64, fmin=0.0, fmax=8000.0, htk=False)\n",
+    "    mel_basis = librosa.filters.mel(sr=sampling_rate, n_fft=512, n_mels=64, fmin=0.0, fmax=8000.0, htk=False)\n",
     "    return mel_basis, spec\n",
     "\n",
     "\n",