Set and tweak global matplotlib configuration in tutorials (#3515)

Summary:
- Set global matplotlib rc params
- Fix style check
- Fix and updates FA tutorial plots
- Add av-asr index cars

Pull Request resolved: https://github.com/pytorch/audio/pull/3515

Reviewed By: huangruizhe

Differential Revision: D47894156

Pulled By: mthrok

fbshipit-source-id: b40d8d31f12ffc2b337e35e632afc216e9d59a6e

docs/source/conf.py

@@ -127,6 +127,22 @@ def _get_pattern():
     return ret
 
 
+def reset_mpl(gallery_conf, fname):
+    from sphinx_gallery.scrapers import _reset_matplotlib
+
+    _reset_matplotlib(gallery_conf, fname)
+    import matplotlib
+
+    matplotlib.rcParams.update(
+        {
+            "image.interpolation": "none",
+            "figure.figsize": (9.6, 4.8),
+            "font.size": 8.0,
+            "axes.axisbelow": True,
+        }
+    )
+
+
 sphinx_gallery_conf = {
     "examples_dirs": [
         "../../examples/tutorials",
@@ -139,6 +155,7 @@ sphinx_gallery_conf = {
     "promote_jupyter_magic": True,
     "first_notebook_cell": None,
     "doc_module": ("torchaudio",),
+    "reset_modules": (reset_mpl, "seaborn"),
 }
 autosummary_generate = True
 

docs/source/index.rst

@@ -71,8 +71,8 @@ model implementations and application components.
    tutorials/online_asr_tutorial
    tutorials/device_asr
    tutorials/device_avsr
-   tutorials/forced_alignment_for_multilingual_data_tutorial
    tutorials/forced_alignment_tutorial
+   tutorials/forced_alignment_for_multilingual_data_tutorial
    tutorials/tacotron2_pipeline_tutorial
    tutorials/mvdr_tutorial
    tutorials/hybrid_demucs_tutorial
@@ -147,6 +147,13 @@ Tutorials
 
 .. customcardstart::
 
+.. customcarditem::
+   :header: On device audio-visual automatic speech recognition
+   :card_description: Learn how to stream audio and video from laptop webcam and perform audio-visual automatic speech recognition using Emformer-RNNT model.
+   :image: https://download.pytorch.org/torchaudio/doc-assets/avsr/transformed.gif
+   :link: tutorials/device_avsr.html
+   :tags: I/O,Pipelines,RNNT
+
 .. customcarditem::
    :header: Loading waveform Tensors from files and saving them
    :card_description: Learn how to query/load audio files and save waveform tensors to files, using <code>torchaudio.info</code>, <code>torchaudio.load</code> and <code>torchaudio.save</code> functions.

examples/tutorials/additive_synthesis_tutorial.py

@@ -85,7 +85,7 @@ NUM_FRAMES = int(DURATION * SAMPLE_RATE)
 #
 
 
-def show(freq, amp, waveform, sample_rate, zoom=None, vol=0.1):
+def plot(freq, amp, waveform, sample_rate, zoom=None, vol=0.1):
     t = torch.arange(waveform.size(0)) / sample_rate
 
     fig, axes = plt.subplots(4, 1, sharex=True)
@@ -101,7 +101,7 @@ def show(freq, amp, waveform, sample_rate, zoom=None, vol=0.1):
     for i in range(4):
         axes[i].grid(True)
     pos = axes[2].get_position()
-    plt.tight_layout()
+    fig.tight_layout()
 
     if zoom is not None:
         ax = fig.add_axes([pos.x0 + 0.02, pos.y0 + 0.03, pos.width / 2.5, pos.height / 2.0])
@@ -168,7 +168,7 @@ def sawtooth_wave(freq0, amp0, num_pitches, sample_rate):
 freq0 = torch.full((NUM_FRAMES, 1), F0)
 amp0 = torch.ones((NUM_FRAMES, 1))
 freq, amp, waveform = sawtooth_wave(freq0, amp0, int(SAMPLE_RATE / F0), SAMPLE_RATE)
-show(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
+plot(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
 
 ######################################################################
 #
@@ -183,7 +183,7 @@ phase = torch.linspace(0, fm * PI2 * DURATION, NUM_FRAMES)
 freq0 = F0 + f_dev * torch.sin(phase).unsqueeze(-1)
 
 freq, amp, waveform = sawtooth_wave(freq0, amp0, int(SAMPLE_RATE / F0), SAMPLE_RATE)
-show(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
+plot(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
 
 ######################################################################
 # Square wave
@@ -220,7 +220,7 @@ def square_wave(freq0, amp0, num_pitches, sample_rate):
 freq0 = torch.full((NUM_FRAMES, 1), F0)
 amp0 = torch.ones((NUM_FRAMES, 1))
 freq, amp, waveform = square_wave(freq0, amp0, int(SAMPLE_RATE / F0 / 2), SAMPLE_RATE)
-show(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
+plot(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
 
 ######################################################################
 # Triangle wave
@@ -256,7 +256,7 @@ def triangle_wave(freq0, amp0, num_pitches, sample_rate):
 #
 
 freq, amp, waveform = triangle_wave(freq0, amp0, int(SAMPLE_RATE / F0 / 2), SAMPLE_RATE)
-show(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
+plot(freq, amp, waveform, SAMPLE_RATE, zoom=(1 / F0, 3 / F0))
 
 ######################################################################
 # Inharmonic Paritials
@@ -296,7 +296,7 @@ amp = torch.stack([amp * (0.5**i) for i in range(num_tones)], dim=-1)
 
 waveform = oscillator_bank(freq, amp, sample_rate=SAMPLE_RATE)
 
-show(freq, amp, waveform, SAMPLE_RATE, vol=0.4)
+plot(freq, amp, waveform, SAMPLE_RATE, vol=0.4)
 
 ######################################################################
 #
@@ -308,7 +308,7 @@ show(freq, amp, waveform, SAMPLE_RATE, vol=0.4)
 freq = extend_pitch(freq0, num_tones)
 waveform = oscillator_bank(freq, amp, sample_rate=SAMPLE_RATE)
 
-show(freq, amp, waveform, SAMPLE_RATE)
+plot(freq, amp, waveform, SAMPLE_RATE)
 
 ######################################################################
 # References

examples/tutorials/asr_inference_with_ctc_decoder_tutorial.py

@@ -407,30 +407,45 @@ print(timesteps, timesteps.shape[0])
 #
 
 
-def plot_alignments(waveform, emission, tokens, timesteps):
-    fig, ax = plt.subplots(figsize=(32, 10))
-
-    ax.plot(waveform)
-
-    ratio = waveform.shape[0] / emission.shape[1]
-    word_start = 0
-
-    for i in range(len(tokens)):
-        if i != 0 and tokens[i - 1] == "|":
-            word_start = timesteps[i]
-        if tokens[i] != "|":
-            plt.annotate(tokens[i].upper(), (timesteps[i] * ratio, waveform.max() * 1.02), size=14)
-        elif i != 0:
-            word_end = timesteps[i]
-            ax.axvspan(word_start * ratio, word_end * ratio, alpha=0.1, color="red")
-
-    xticks = ax.get_xticks()
-    plt.xticks(xticks, xticks / bundle.sample_rate)
-    ax.set_xlabel("time (sec)")
-    ax.set_xlim(0, waveform.shape[0])
-
-
-plot_alignments(waveform[0], emission, predicted_tokens, timesteps)
+def plot_alignments(waveform, emission, tokens, timesteps, sample_rate):
+
+    t = torch.arange(waveform.size(0)) / sample_rate
+    ratio = waveform.size(0) / emission.size(1) / sample_rate
+
+    chars = []
+    words = []
+    word_start = None
+    for token, timestep in zip(tokens, timesteps * ratio):
+        if token == "|":
+            if word_start is not None:
+                words.append((word_start, timestep))
+            word_start = None
+        else:
+            chars.append((token, timestep))
+            if word_start is None:
+                word_start = timestep
+
+    fig, axes = plt.subplots(3, 1)
+
+    def _plot(ax, xlim):
+        ax.plot(t, waveform)
+        for token, timestep in chars:
+            ax.annotate(token.upper(), (timestep, 0.5))
+        for word_start, word_end in words:
+            ax.axvspan(word_start, word_end, alpha=0.1, color="red")
+        ax.set_ylim(-0.6, 0.7)
+        ax.set_yticks([0])
+        ax.grid(True, axis="y")
+        ax.set_xlim(xlim)
+
+    _plot(axes[0], (0.3, 2.5))
+    _plot(axes[1], (2.5, 4.7))
+    _plot(axes[2], (4.7, 6.9))
+    axes[2].set_xlabel("time (sec)")
+    fig.tight_layout()
+
+
+plot_alignments(waveform[0], emission, predicted_tokens, timesteps, bundle.sample_rate)
 
 
 ######################################################################

examples/tutorials/audio_data_augmentation_tutorial.py

@@ -100,7 +100,6 @@ def plot_waveform(waveform, sample_rate, title="Waveform", xlim=None):
         if xlim:
             axes[c].set_xlim(xlim)
     figure.suptitle(title)
-    plt.show(block=False)
 
 
 ######################################################################
@@ -122,7 +121,6 @@ def plot_specgram(waveform, sample_rate, title="Spectrogram", xlim=None):
         if xlim:
             axes[c].set_xlim(xlim)
     figure.suptitle(title)
-    plt.show(block=False)
 
 
 ######################################################################

examples/tutorials/audio_datasets_tutorial.py

-# -*- coding: utf-8 -*-
 """
 Audio Datasets
 ==============
@@ -10,10 +9,6 @@ datasets. Please refer to the official documentation for the list of
 available datasets.
 """
 
-# When running this tutorial in Google Colab, install the required packages
-# with the following.
-# !pip install torchaudio
-
 import torch
 import torchaudio
 
@@ -21,22 +16,13 @@ print(torch.__version__)
 print(torchaudio.__version__)
 
 ######################################################################
-# Preparing data and utility functions (skip this section)
-# --------------------------------------------------------
 #
 
-# @title Prepare data and utility functions. {display-mode: "form"}
-# @markdown
-# @markdown You do not need to look into this cell.
-# @markdown Just execute once and you are good to go.
-
-# -------------------------------------------------------------------------------
-# Preparation of data and helper functions.
-# -------------------------------------------------------------------------------
 import os
 
+import IPython
+
 import matplotlib.pyplot as plt
-from IPython.display import Audio, display
 
 
 _SAMPLE_DIR = "_assets"
@@ -44,34 +30,13 @@ YESNO_DATASET_PATH = os.path.join(_SAMPLE_DIR, "yes_no")
 os.makedirs(YESNO_DATASET_PATH, exist_ok=True)
 
 
-def plot_specgram(waveform, sample_rate, title="Spectrogram", xlim=None):
+def plot_specgram(waveform, sample_rate, title="Spectrogram"):
     waveform = waveform.numpy()
 
-    num_channels, _ = waveform.shape
-
-    figure, axes = plt.subplots(num_channels, 1)
-    if num_channels == 1:
-        axes = [axes]
-    for c in range(num_channels):
-        axes[c].specgram(waveform[c], Fs=sample_rate)
-        if num_channels > 1:
-            axes[c].set_ylabel(f"Channel {c+1}")
-        if xlim:
-            axes[c].set_xlim(xlim)
+    figure, ax = plt.subplots()
+    ax.specgram(waveform[0], Fs=sample_rate)
     figure.suptitle(title)
-    plt.show(block=False)
-
-
-def play_audio(waveform, sample_rate):
-    waveform = waveform.numpy()
-
-    num_channels, _ = waveform.shape
-    if num_channels == 1:
-        display(Audio(waveform[0], rate=sample_rate))
-    elif num_channels == 2:
-        display(Audio((waveform[0], waveform[1]), rate=sample_rate))
-    else:
-        raise ValueError("Waveform with more than 2 channels are not supported.")
+    figure.tight_layout()
 
 
 ######################################################################
@@ -79,10 +44,25 @@ def play_audio(waveform, sample_rate):
 # :py:class:`torchaudio.datasets.YESNO` dataset.
 #
 
-
 dataset = torchaudio.datasets.YESNO(YESNO_DATASET_PATH, download=True)
 
-for i in [1, 3, 5]:
-    waveform, sample_rate, label = dataset[i]
-    plot_specgram(waveform, sample_rate, title=f"Sample {i}: {label}")
-    play_audio(waveform, sample_rate)
+######################################################################
+#
+i = 1
+waveform, sample_rate, label = dataset[i]
+plot_specgram(waveform, sample_rate, title=f"Sample {i}: {label}")
+IPython.display.Audio(waveform, rate=sample_rate)
+
+######################################################################
+#
+i = 3
+waveform, sample_rate, label = dataset[i]
+plot_specgram(waveform, sample_rate, title=f"Sample {i}: {label}")
+IPython.display.Audio(waveform, rate=sample_rate)
+
+######################################################################
+#
+i = 5
+waveform, sample_rate, label = dataset[i]
+plot_specgram(waveform, sample_rate, title=f"Sample {i}: {label}")
+IPython.display.Audio(waveform, rate=sample_rate)

examples/tutorials/audio_feature_augmentation_tutorial.py

@@ -19,25 +19,19 @@ print(torch.__version__)
 print(torchaudio.__version__)
 
 ######################################################################
-# Preparing data and utility functions (skip this section)
-# --------------------------------------------------------
+# Preparation
+# -----------
 #
 
-# @title Prepare data and utility functions. {display-mode: "form"}
-# @markdown
-# @markdown You do not need to look into this cell.
-# @markdown Just execute once and you are good to go.
-# @markdown
-# @markdown In this tutorial, we will use a speech data from [VOiCES dataset](https://iqtlabs.github.io/voices/),
-# @markdown which is licensed under Creative Commos BY 4.0.
-
-# -------------------------------------------------------------------------------
-# Preparation of data and helper functions.
-# -------------------------------------------------------------------------------
 import librosa
 import matplotlib.pyplot as plt
 from torchaudio.utils import download_asset
 
+######################################################################
+# In this tutorial, we will use a speech data from
+# `VOiCES dataset <https://iqtlabs.github.io/voices/>`__,
+# which is licensed under Creative Commos BY 4.0.
+
 SAMPLE_WAV_SPEECH_PATH = download_asset("tutorial-assets/Lab41-SRI-VOiCES-src-sp0307-ch127535-sg0042.wav")
 
 
@@ -75,16 +69,9 @@ def get_spectrogram(
     return spectrogram(waveform)
 
 
-def plot_spectrogram(spec, title=None, ylabel="freq_bin", aspect="auto", xmax=None):
-    fig, axs = plt.subplots(1, 1)
-    axs.set_title(title or "Spectrogram (db)")
-    axs.set_ylabel(ylabel)
-    axs.set_xlabel("frame")
-    im = axs.imshow(librosa.power_to_db(spec), origin="lower", aspect=aspect)
-    if xmax:
-        axs.set_xlim((0, xmax))
-    fig.colorbar(im, ax=axs)
-    plt.show(block=False)
+def plot_spec(ax, spec, title, ylabel="freq_bin"):
+    ax.set_title(title)
+    ax.imshow(librosa.power_to_db(spec), origin="lower", aspect="auto")
 
 
 ######################################################################
@@ -108,43 +95,47 @@ def plot_spectrogram(spec, title=None, ylabel="freq_bin", aspect="auto", xmax=No
 spec = get_spectrogram(power=None)
 stretch = T.TimeStretch()
 
-rate = 1.2
-spec_ = stretch(spec, rate)
-plot_spectrogram(torch.abs(spec_[0]), title=f"Stretched x{rate}", aspect="equal", xmax=304)
-
-plot_spectrogram(torch.abs(spec[0]), title="Original", aspect="equal", xmax=304)
-
-rate = 0.9
-spec_ = stretch(spec, rate)
-plot_spectrogram(torch.abs(spec_[0]), title=f"Stretched x{rate}", aspect="equal", xmax=304)
+spec_12 = stretch(spec, overriding_rate=1.2)
+spec_09 = stretch(spec, overriding_rate=0.9)
 
 ######################################################################
-# TimeMasking
-# -----------
 #
 
-torch.random.manual_seed(4)
 
-spec = get_spectrogram()
-plot_spectrogram(spec[0], title="Original")
+def plot():
+    fig, axes = plt.subplots(3, 1, sharex=True, sharey=True)
+    plot_spec(axes[0], torch.abs(spec_12[0]), title="Stretched x1.2")
+    plot_spec(axes[1], torch.abs(spec[0]), title="Original")
+    plot_spec(axes[2], torch.abs(spec_09[0]), title="Stretched x0.9")
+    fig.tight_layout()
 
-masking = T.TimeMasking(time_mask_param=80)
-spec = masking(spec)
 
-plot_spectrogram(spec[0], title="Masked along time axis")
+plot()
 
 ######################################################################
-# FrequencyMasking
-# ----------------
+# Time and Frequency Masking
+# --------------------------
 #
 
-
 torch.random.manual_seed(4)
 
+time_masking = T.TimeMasking(time_mask_param=80)
+freq_masking = T.FrequencyMasking(freq_mask_param=80)
+
 spec = get_spectrogram()
-plot_spectrogram(spec[0], title="Original")
+time_masked = time_masking(spec)
+freq_masked = freq_masking(spec)
+
+######################################################################
+#
+
+
+def plot():
+    fig, axes = plt.subplots(3, 1, sharex=True, sharey=True)
+    plot_spec(axes[0], spec[0], title="Original")
+    plot_spec(axes[1], time_masked[0], title="Masked along time axis")
+    plot_spec(axes[2], freq_masked[0], title="Masked along frequency axis")
+    fig.tight_layout()
 
-masking = T.FrequencyMasking(freq_mask_param=80)
-spec = masking(spec)
 
-plot_spectrogram(spec[0], title="Masked along frequency axis")
+plot()

examples/tutorials/audio_feature_extractions_tutorial.py

@@ -75,7 +75,6 @@ def plot_waveform(waveform, sr, title="Waveform", ax=None):
     ax.grid(True)
     ax.set_xlim([0, time_axis[-1]])
     ax.set_title(title)
-    plt.show(block=False)
 
 
 def plot_spectrogram(specgram, title=None, ylabel="freq_bin", ax=None):
@@ -85,7 +84,6 @@ def plot_spectrogram(specgram, title=None, ylabel="freq_bin", ax=None):
         ax.set_title(title)
     ax.set_ylabel(ylabel)
     ax.imshow(librosa.power_to_db(specgram), origin="lower", aspect="auto", interpolation="nearest")
-    plt.show(block=False)
 
 
 def plot_fbank(fbank, title=None):
@@ -94,7 +92,6 @@ def plot_fbank(fbank, title=None):
     axs.imshow(fbank, aspect="auto")
     axs.set_ylabel("frequency bin")
     axs.set_xlabel("mel bin")
-    plt.show(block=False)
 
 
 ######################################################################
@@ -486,7 +483,6 @@ def plot_pitch(waveform, sr, pitch):
     axis2.plot(time_axis, pitch[0], linewidth=2, label="Pitch", color="green")
 
     axis2.legend(loc=0)
-    plt.show(block=False)
 
 
 plot_pitch(SPEECH_WAVEFORM, SAMPLE_RATE, pitch)

examples/tutorials/audio_io_tutorial.py

@@ -181,7 +181,6 @@ def plot_waveform(waveform, sample_rate):
         if num_channels > 1:
             axes[c].set_ylabel(f"Channel {c+1}")
     figure.suptitle("waveform")
-    plt.show(block=False)
 
 
 ######################################################################
@@ -204,7 +203,6 @@ def plot_specgram(waveform, sample_rate, title="Spectrogram"):
         if num_channels > 1:
             axes[c].set_ylabel(f"Channel {c+1}")
     figure.suptitle(title)
-    plt.show(block=False)
 
 
 ######################################################################

examples/tutorials/audio_resampling_tutorial.py

@@ -105,7 +105,6 @@ def plot_sweep(
     axis.yaxis.grid(True, alpha=0.67)
     figure.suptitle(f"{title} (sample rate: {sample_rate} Hz)")
     plt.colorbar(cax)
-    plt.show(block=True)
 
 
 ######################################################################

examples/tutorials/device_avsr.py

@@ -69,7 +69,7 @@ import torchvision
 # -------------------
 #
 # Firstly, we define the function to collect videos from microphone and
-# camera. To be specific, we use :py:func:`~torchaudio.io.StreamReader`
+# camera. To be specific, we use :py:class:`~torchaudio.io.StreamReader`
 # class for the purpose of data collection, which supports capturing
 # audio/video from microphone and camera. For the detailed usage of this
 # class, please refer to the

examples/tutorials/filter_design_tutorial.py

@@ -89,7 +89,7 @@ def plot_sinc_ir(irs, cutoff):
     num_filts, window_size = irs.shape
     half = window_size // 2
 
-    fig, axes = plt.subplots(num_filts, 1, sharex=True, figsize=(6.4, 4.8 * 1.5))
+    fig, axes = plt.subplots(num_filts, 1, sharex=True, figsize=(9.6, 8))
     t = torch.linspace(-half, half - 1, window_size)
     for ax, ir, coff, color in zip(axes, irs, cutoff, plt.cm.tab10.colors):
         ax.plot(t, ir, linewidth=1.2, color=color, zorder=4, label=f"Cutoff: {coff}")
@@ -100,7 +100,7 @@ def plot_sinc_ir(irs, cutoff):
         "(Frequencies are relative to Nyquist frequency)"
     )
     axes[-1].set_xticks([i * half // 4 for i in range(-4, 5)])
-    plt.tight_layout()
+    fig.tight_layout()
 
 
 ######################################################################
@@ -130,7 +130,7 @@ def plot_sinc_fr(frs, cutoff, band=False):
     num_filts, num_fft = frs.shape
     num_ticks = num_filts + 1 if band else num_filts
 
-    fig, axes = plt.subplots(num_filts, 1, sharex=True, sharey=True, figsize=(6.4, 4.8 * 1.5))
+    fig, axes = plt.subplots(num_filts, 1, sharex=True, sharey=True, figsize=(9.6, 8))
     for ax, fr, coff, color in zip(axes, frs, cutoff, plt.cm.tab10.colors):
         ax.grid(True)
         ax.semilogy(fr, color=color, zorder=4, label=f"Cutoff: {coff}")
@@ -146,7 +146,7 @@ def plot_sinc_fr(frs, cutoff, band=False):
         "Frequency response of sinc low-pass filter for different cut-off frequencies\n"
         "(Frequencies are relative to Nyquist frequency)"
     )
-    plt.tight_layout()
+    fig.tight_layout()
 
 
 ######################################################################
@@ -275,7 +275,7 @@ def plot_ir(magnitudes, ir, num_fft=2048):
         axes[i].grid(True)
     axes[1].set(title="Frequency Response")
     axes[2].set(title="Frequency Response (log-scale)", xlabel="Frequency")
-    axes[2].legend(loc="lower right")
+    axes[2].legend(loc="center right")
     fig.tight_layout()
 
 

examples/tutorials/forced_alignment_tutorial.py

@@ -56,16 +56,11 @@ print(device)
 # First we import the necessary packages, and fetch data that we work on.
 #
 
-# %matplotlib inline
-
 from dataclasses import dataclass
 
 import IPython
-import matplotlib
 import matplotlib.pyplot as plt
 
-matplotlib.rcParams["figure.figsize"] = [16.0, 4.8]
-
 torch.random.manual_seed(0)
 
 SPEECH_FILE = torchaudio.utils.download_asset("tutorial-assets/Lab41-SRI-VOiCES-src-sp0307-ch127535-sg0042.wav")
@@ -99,17 +94,22 @@ with torch.inference_mode():
 
 emission = emissions[0].cpu().detach()
 
+print(labels)
+
 ################################################################################
 # Visualization
-################################################################################
-print(labels)
-plt.imshow(emission.T)
-plt.colorbar()
-plt.title("Frame-wise class probability")
-plt.xlabel("Time")
-plt.ylabel("Labels")
-plt.show()
+# ~~~~~~~~~~~~~
+
 
+def plot():
+    plt.imshow(emission.T)
+    plt.colorbar()
+    plt.title("Frame-wise class probability")
+    plt.xlabel("Time")
+    plt.ylabel("Labels")
+
+
+plot()
 
 ######################################################################
 # Generate alignment probability (trellis)
@@ -181,12 +181,17 @@ trellis = get_trellis(emission, tokens)
 
 ################################################################################
 # Visualization
-################################################################################
-plt.imshow(trellis.T, origin="lower")
-plt.annotate("- Inf", (trellis.size(1) / 5, trellis.size(1) / 1.5))
-plt.annotate("+ Inf", (trellis.size(0) - trellis.size(1) / 5, trellis.size(1) / 3))
-plt.colorbar()
-plt.show()
+# ~~~~~~~~~~~~~
+
+
+def plot():
+    plt.imshow(trellis.T, origin="lower")
+    plt.annotate("- Inf", (trellis.size(1) / 5, trellis.size(1) / 1.5))
+    plt.annotate("+ Inf", (trellis.size(0) - trellis.size(1) / 5, trellis.size(1) / 3))
+    plt.colorbar()
+
+
+plot()
 
 ######################################################################
 # In the above visualization, we can see that there is a trace of high
@@ -266,7 +271,9 @@ for p in path:
 
 ################################################################################
 # Visualization
-################################################################################
+# ~~~~~~~~~~~~~
+
+
 def plot_trellis_with_path(trellis, path):
     # To plot trellis with path, we take advantage of 'nan' value
     trellis_with_path = trellis.clone()
@@ -277,10 +284,14 @@ def plot_trellis_with_path(trellis, path):
 
 plot_trellis_with_path(trellis, path)
 plt.title("The path found by backtracking")
-plt.show()
 
 ######################################################################
-# Looking good. Now this path contains repetations for the same labels, so
+# Looking good.
+
+######################################################################
+# Segment the path
+# ----------------
+# Now this path contains repetations for the same labels, so
 # let’s merge them to make it close to the original transcript.
 #
 # When merging the multiple path points, we simply take the average
@@ -297,7 +308,7 @@ class Segment:
     score: float
 
     def __repr__(self):
-        return f"{self.label}\t({self.score:4.2f}): [{self.start:5d}, {self.end:5d})"
+        return f"{self.label} ({self.score:4.2f}): [{self.start:5d}, {self.end:5d})"
 
     @property
     def length(self):
@@ -330,7 +341,9 @@ for seg in segments:
 
 ################################################################################
 # Visualization
-################################################################################
+# ~~~~~~~~~~~~~
+
+
 def plot_trellis_with_segments(trellis, segments, transcript):
     # To plot trellis with path, we take advantage of 'nan' value
     trellis_with_path = trellis.clone()
@@ -338,15 +351,14 @@ def plot_trellis_with_segments(trellis, segments, transcript):
         if seg.label != "|":
             trellis_with_path[seg.start : seg.end, i] = float("nan")
 
-    fig, [ax1, ax2] = plt.subplots(2, 1, figsize=(16, 9.5))
+    fig, [ax1, ax2] = plt.subplots(2, 1, sharex=True)
     ax1.set_title("Path, label and probability for each label")
-    ax1.imshow(trellis_with_path.T, origin="lower")
-    ax1.set_xticks([])
+    ax1.imshow(trellis_with_path.T, origin="lower", aspect="auto")
 
     for i, seg in enumerate(segments):
         if seg.label != "|":
-            ax1.annotate(seg.label, (seg.start, i - 0.7), weight="bold")
-            ax1.annotate(f"{seg.score:.2f}", (seg.start, i + 3))
+            ax1.annotate(seg.label, (seg.start, i - 0.7), size="small")
+            ax1.annotate(f"{seg.score:.2f}", (seg.start, i + 3), size="small")
 
     ax2.set_title("Label probability with and without repetation")
     xs, hs, ws = [], [], []
@@ -355,7 +367,7 @@ def plot_trellis_with_segments(trellis, segments, transcript):
             xs.append((seg.end + seg.start) / 2 + 0.4)
             hs.append(seg.score)
             ws.append(seg.end - seg.start)
-            ax2.annotate(seg.label, (seg.start + 0.8, -0.07), weight="bold")
+            ax2.annotate(seg.label, (seg.start + 0.8, -0.07))
     ax2.bar(xs, hs, width=ws, color="gray", alpha=0.5, edgecolor="black")
 
     xs, hs = [], []
@@ -367,17 +379,21 @@ def plot_trellis_with_segments(trellis, segments, transcript):
 
     ax2.bar(xs, hs, width=0.5, alpha=0.5)
     ax2.axhline(0, color="black")
-    ax2.set_xlim(ax1.get_xlim())
+    ax2.grid(True, axis="y")
     ax2.set_ylim(-0.1, 1.1)
+    fig.tight_layout()
 
 
 plot_trellis_with_segments(trellis, segments, transcript)
-plt.tight_layout()
-plt.show()
 
 
 ######################################################################
-# Looks good. Now let’s merge the words. The Wav2Vec2 model uses ``'|'``
+# Looks good.
+
+######################################################################
+# Merge the segments into words
+# -----------------------------
+# Now let’s merge the words. The Wav2Vec2 model uses ``'|'``
 # as the word boundary, so we merge the segments before each occurance of
 # ``'|'``.
 #
@@ -410,16 +426,16 @@ for word in word_segments:
 
 ################################################################################
 # Visualization
-################################################################################
+# ~~~~~~~~~~~~~
 def plot_alignments(trellis, segments, word_segments, waveform):
     trellis_with_path = trellis.clone()
     for i, seg in enumerate(segments):
         if seg.label != "|":
             trellis_with_path[seg.start : seg.end, i] = float("nan")
 
-    fig, [ax1, ax2] = plt.subplots(2, 1, figsize=(16, 9.5))
+    fig, [ax1, ax2] = plt.subplots(2, 1)
 
-    ax1.imshow(trellis_with_path.T, origin="lower")
+    ax1.imshow(trellis_with_path.T, origin="lower", aspect="auto")
     ax1.set_xticks([])
     ax1.set_yticks([])
 
@@ -429,8 +445,8 @@ def plot_alignments(trellis, segments, word_segments, waveform):
 
     for i, seg in enumerate(segments):
         if seg.label != "|":
-            ax1.annotate(seg.label, (seg.start, i - 0.7))
-            ax1.annotate(f"{seg.score:.2f}", (seg.start, i + 3), fontsize=8)
+            ax1.annotate(seg.label, (seg.start, i - 0.7), size="small")
+            ax1.annotate(f"{seg.score:.2f}", (seg.start, i + 3), size="small")
 
     # The original waveform
     ratio = waveform.size(0) / trellis.size(0)
@@ -450,6 +466,7 @@ def plot_alignments(trellis, segments, word_segments, waveform):
     ax2.set_yticks([])
     ax2.set_ylim(-1.0, 1.0)
     ax2.set_xlim(0, waveform.size(-1))
+    fig.tight_layout()
 
 
 plot_alignments(
@@ -458,7 +475,6 @@ plot_alignments(
     word_segments,
     waveform[0],
 )
-plt.show()
 
 
 ################################################################################

examples/tutorials/hybrid_demucs_tutorial.py

@@ -162,11 +162,10 @@ def separate_sources(
 def plot_spectrogram(stft, title="Spectrogram"):
     magnitude = stft.abs()
     spectrogram = 20 * torch.log10(magnitude + 1e-8).numpy()
-    figure, axis = plt.subplots(1, 1)
-    img = axis.imshow(spectrogram, cmap="viridis", vmin=-60, vmax=0, origin="lower", aspect="auto")
-    figure.suptitle(title)
-    plt.colorbar(img, ax=axis)
-    plt.show()
+    _, axis = plt.subplots(1, 1)
+    axis.imshow(spectrogram, cmap="viridis", vmin=-60, vmax=0, origin="lower", aspect="auto")
+    axis.set_title(title)
+    plt.tight_layout()
 
 
 ######################################################################
@@ -252,7 +251,7 @@ def output_results(original_source: torch.Tensor, predicted_source: torch.Tensor
         "SDR score is:",
         separation.bss_eval_sources(original_source.detach().numpy(), predicted_source.detach().numpy())[0].mean(),
     )
-    plot_spectrogram(stft(predicted_source)[0], f"Spectrogram {source}")
+    plot_spectrogram(stft(predicted_source)[0], f"Spectrogram - {source}")
     return Audio(predicted_source, rate=sample_rate)
 
 
@@ -294,7 +293,7 @@ mix_spec = mixture[:, frame_start:frame_end].cpu()
 #
 
 # Mixture Clip
-plot_spectrogram(stft(mix_spec)[0], "Spectrogram Mixture")
+plot_spectrogram(stft(mix_spec)[0], "Spectrogram - Mixture")
 Audio(mix_spec, rate=sample_rate)
 
 ######################################################################

examples/tutorials/mvdr_tutorial.py

@@ -98,23 +98,21 @@ SAMPLE_NOISE = download_asset("tutorial-assets/mvdr/noise.wav")
 #
 
 
-def plot_spectrogram(stft, title="Spectrogram", xlim=None):
+def plot_spectrogram(stft, title="Spectrogram"):
     magnitude = stft.abs()
     spectrogram = 20 * torch.log10(magnitude + 1e-8).numpy()
     figure, axis = plt.subplots(1, 1)
     img = axis.imshow(spectrogram, cmap="viridis", vmin=-100, vmax=0, origin="lower", aspect="auto")
-    figure.suptitle(title)
+    axis.set_title(title)
     plt.colorbar(img, ax=axis)
-    plt.show()
 
 
-def plot_mask(mask, title="Mask", xlim=None):
+def plot_mask(mask, title="Mask"):
     mask = mask.numpy()
     figure, axis = plt.subplots(1, 1)
     img = axis.imshow(mask, cmap="viridis", origin="lower", aspect="auto")
-    figure.suptitle(title)
+    axis.set_title(title)
     plt.colorbar(img, ax=axis)
-    plt.show()
 
 
 def si_snr(estimate, reference, epsilon=1e-8):

examples/tutorials/nvdec_tutorial.py

@@ -33,12 +33,9 @@ print(torchaudio.__version__)
 import os
 import time
 
-import matplotlib
 import matplotlib.pyplot as plt
 from torchaudio.io import StreamReader
 
-matplotlib.rcParams["image.interpolation"] = "none"
-
 ######################################################################
 #
 # Check the prerequisites

examples/tutorials/speech_recognition_pipeline_tutorial.py

@@ -160,8 +160,7 @@ for i, feats in enumerate(features):
     ax[i].set_title(f"Feature from transformer layer {i+1}")
     ax[i].set_xlabel("Feature dimension")
     ax[i].set_ylabel("Frame (time-axis)")
-plt.tight_layout()
-plt.show()
+fig.tight_layout()
 
 
 ######################################################################
@@ -190,7 +189,7 @@ plt.imshow(emission[0].cpu().T, interpolation="nearest")
 plt.title("Classification result")
 plt.xlabel("Frame (time-axis)")
 plt.ylabel("Class")
-plt.show()
+plt.tight_layout()
 print("Class labels:", bundle.get_labels())
 
 

examples/tutorials/squim_tutorial.py

@@ -82,19 +82,23 @@ try:
     from pystoi import stoi
     from torchaudio.pipelines import SQUIM_OBJECTIVE, SQUIM_SUBJECTIVE
 except ImportError:
-    import google.colab  # noqa: F401
-
-    print(
-        """
-        To enable running this notebook in Google Colab, install nightly
-        torch and torchaudio builds by adding the following code block to the top
-        of the notebook before running it:
-        !pip3 uninstall -y torch torchvision torchaudio
-        !pip3 install --pre torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/nightly/cpu
-        !pip3 install pesq
-        !pip3 install pystoi
-        """
-    )
+    try:
+        import google.colab  # noqa: F401
+
+        print(
+            """
+            To enable running this notebook in Google Colab, install nightly
+            torch and torchaudio builds by adding the following code block to the top
+            of the notebook before running it:
+            !pip3 uninstall -y torch torchvision torchaudio
+            !pip3 install --pre torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/nightly/cpu
+            !pip3 install pesq
+            !pip3 install pystoi
+            """
+        )
+    except Exception:
+        pass
+    raise
 
 
 import matplotlib.pyplot as plt
@@ -128,27 +132,17 @@ def si_snr(estimate, reference, epsilon=1e-8):
     return si_snr.item()
 
 
-def plot_waveform(waveform, title):
+def plot(waveform, title, sample_rate=16000):
     wav_numpy = waveform.numpy()
 
     sample_size = waveform.shape[1]
-    time_axis = torch.arange(0, sample_size) / 16000
-
-    figure, axes = plt.subplots(1, 1)
-    axes = figure.gca()
-    axes.plot(time_axis, wav_numpy[0], linewidth=1)
-    axes.grid(True)
-    figure.suptitle(title)
-    plt.show(block=False)
+    time_axis = torch.arange(0, sample_size) / sample_rate
 
-
-def plot_specgram(waveform, sample_rate, title):
-    wav_numpy = waveform.numpy()
-    figure, axes = plt.subplots(1, 1)
-    axes = figure.gca()
-    axes.specgram(wav_numpy[0], Fs=sample_rate)
+    figure, axes = plt.subplots(2, 1)
+    axes[0].plot(time_axis, wav_numpy[0], linewidth=1)
+    axes[0].grid(True)
+    axes[1].specgram(wav_numpy[0], Fs=sample_rate)
     figure.suptitle(title)
-    plt.show(block=False)
 
 
 ######################################################################
@@ -238,32 +232,28 @@ Audio(WAVEFORM_DISTORTED.numpy()[1], rate=16000)
 # Visualize speech sample
 #
 
-plot_waveform(WAVEFORM_SPEECH, "Clean Speech")
-plot_specgram(WAVEFORM_SPEECH, 16000, "Clean Speech Spectrogram")
+plot(WAVEFORM_SPEECH, "Clean Speech")
 
 
 ######################################################################
 # Visualize noise sample
 #
 
-plot_waveform(WAVEFORM_NOISE, "Noise")
-plot_specgram(WAVEFORM_NOISE, 16000, "Noise Spectrogram")
+plot(WAVEFORM_NOISE, "Noise")
 
 
 ######################################################################
 # Visualize distorted speech with 20dB SNR
 #
 
-plot_waveform(WAVEFORM_DISTORTED[0:1], f"Distorted Speech with {snr_dbs[0]}dB SNR")
-plot_specgram(WAVEFORM_DISTORTED[0:1], 16000, f"Distorted Speech with {snr_dbs[0]}dB SNR")
+plot(WAVEFORM_DISTORTED[0:1], f"Distorted Speech with {snr_dbs[0]}dB SNR")
 
 
 ######################################################################
 # Visualize distorted speech with -5dB SNR
 #
 
-plot_waveform(WAVEFORM_DISTORTED[1:2], f"Distorted Speech with {snr_dbs[1]}dB SNR")
-plot_specgram(WAVEFORM_DISTORTED[1:2], 16000, f"Distorted Speech with {snr_dbs[1]}dB SNR")
+plot(WAVEFORM_DISTORTED[1:2], f"Distorted Speech with {snr_dbs[1]}dB SNR")
 
 
 ######################################################################