def spectrogram_summary(audio, audio_gen, step, name='', tag='spectrogram'):
"""Writes a summary of spectrograms for a batch of images."""
specgram = lambda a: ddsp.spectral_ops.compute_logmag(tf_float32(a),
size=768)
# Batch spectrogram operations
spectrograms = specgram(audio)
spectrograms_gen = specgram(audio_gen)
batch_size = int(audio.shape[0])
for i in range(batch_size):
# Manually specify exact size of fig for tensorboard
fig, axs = plt.subplots(2, 1, figsize=(8, 8))
_plt_spec(spectrograms[i], axs[0], 'original')
_plt_spec(spectrograms_gen[i], axs[1], 'synthesized')
# Format and save plot to image
fig_summary(fig, plot_type='spectrogram', sample_idx=i + 1, **data)
def compute_rms_energy(audio,
sample_rate=16000,
frame_rate=250,
frame_size=2048,
pad_end=True):
"""Compute root mean squared energy of audio."""
audio = tf_float32(audio)
hop_size = sample_rate // frame_rate
audio_frames = tf.signal.frame(audio,
frame_size,
hop_size,
pad_end=pad_end)
rms_energy = tf.reduce_mean(audio_frames**2.0, axis=-1)**0.5
if pad_end:
n_samples = audio.shape[0] if len(audio.shape) == 1 else audio.shape[1]
n_secs = n_samples / float(
sample_rate) # `n_secs` can have milliseconds
expected_len = int(n_secs * frame_rate)
return pad_or_trim_to_expected_length(rms_energy,
expected_len,
use_tf=True)
else:
return rms_energy
def compute_mag(audio, size=2048, overlap=0.75, pad_end=True):
mag = tf.abs(stft(audio, frame_size=size, overlap=overlap,
pad_end=pad_end))
return tf_float32(mag)
def compute_loudness(audio,
sample_rate=16000,
frame_rate=250,
n_fft=2048,
range_db=LD_RANGE,
ref_db=20.7,
use_tf=False):
"""Perceptual loudness in dB, relative to white noise, amplitude=1.
Function is differentiable if use_tf=True.
Args:
audio: Numpy ndarray or tensor. Shape [batch_size, audio_length] or
[batch_size,].
sample_rate: Audio sample rate in Hz.
frame_rate: Rate of loudness frames in Hz.
n_fft: Fft window size.
range_db: Sets the dynamic range of loudness in decibles. The minimum
loudness (per a frequency bin) corresponds to -range_db.
ref_db: Sets the reference maximum perceptual loudness as given by
(A_weighting + 10 * log10(abs(stft(audio))**2.0). The default value
corresponds to white noise with amplitude=1.0 and n_fft=2048. There is a
slight dependence on fft_size due to different granularity of perceptual
weighting.
use_tf: Make function differentiable by using tensorflow.
Returns:
Loudness in decibels. Shape [batch_size, n_frames] or [n_frames,].
"""
if sample_rate % frame_rate != 0:
raise ValueError(
'frame_rate: {} must evenly divide sample_rate: {}.'
'For default frame_rate: 250Hz, suggested sample_rate: 16kHz or 48kHz'
.format(frame_rate, sample_rate))
# Pick tensorflow or numpy.
lib = tf if use_tf else np
# Make inputs tensors for tensorflow.
audio = tf_float32(audio) if use_tf else audio
# Temporarily a batch dimension for single examples.
is_1d = (len(audio.shape) == 1)
audio = audio[lib.newaxis, :] if is_1d else audio
# Take STFT.
hop_size = sample_rate // frame_rate
overlap = 1 - hop_size / n_fft
stft_fn = stft if use_tf else stft_np
s = stft_fn(audio, frame_size=n_fft, overlap=overlap, pad_end=True)
# Compute power.
amplitude = lib.abs(s)
power_db = amplitude_to_db(amplitude, use_tf=use_tf)
# Perceptual weighting.
frequencies = librosa.fft_frequencies(sr=sample_rate, n_fft=n_fft)
a_weighting = librosa.A_weighting(frequencies)[lib.newaxis, lib.newaxis, :]
loudness = power_db + a_weighting
# Set dynamic range.
loudness -= ref_db
loudness = lib.maximum(loudness, -range_db)
mean = tf.reduce_mean if use_tf else np.mean
# Average over frequency bins.
loudness = mean(loudness, axis=-1)
# Remove temporary batch dimension.
loudness = loudness[0] if is_1d else loudness
# Compute expected length of loudness vector
n_secs = audio.shape[-1] / float(
sample_rate) # `n_secs` can have milliseconds
expected_len = int(n_secs * frame_rate)
# Pad with `-range_db` noise floor or trim vector
loudness = pad_or_trim_to_expected_length(loudness,
expected_len,
-range_db,
use_tf=use_tf)
return loudness
def compute_loudness(audio,
sample_rate=16000,
frame_rate=250,
n_fft=2048,
range_db=LD_RANGE,
ref_db=20.7,
use_tf=False):
"""Perceptual loudness in dB, relative to white noise, amplitude=1.
Function is differentiable if use_tf=True.
Args:
audio: Numpy ndarray or tensor. Shape [batch_size, audio_length] or
[batch_size,].
sample_rate: Audio sample rate in Hz.
frame_rate: Rate of loudness frames in Hz.
n_fft: Fft window size.
range_db: Sets the dynamic range of loudness in decibles. The minimum
loudness (per a frequency bin) corresponds to -range_db.
ref_db: Sets the reference maximum perceptual loudness as given by
(A_weighting + 10 * log10(abs(stft(audio))**2.0). The default value
corresponds to white noise with amplitude=1.0 and n_fft=2048. There is a
slight dependence on fft_size due to different granularity of perceptual
weighting.
use_tf: Make function differentiable by using librosa.
Returns:
Loudness in decibels. Shape [batch_size, n_frames] or [n_frames,].
"""
# Pick tensorflow or numpy.
lib = tf if use_tf else np
# Make inputs tensors for tensorflow.
audio = tf_float32(audio) if use_tf else audio
# Temporarily a batch dimension for single examples.
is_1d = (len(audio.shape) == 1)
audio = audio[lib.newaxis, :] if is_1d else audio
# Take STFT.
hop_size = sample_rate // frame_rate
overlap = 1 - hop_size / n_fft
stft_fn = stft if use_tf else stft_np
s = stft_fn(audio, frame_size=n_fft, overlap=overlap, pad_end=True)
# Compute power
amplitude = lib.abs(s)
log10 = (
lambda x: tf.math.log(x) / tf.math.log(10.0)) if use_tf else np.log10
amin = 1e-20 # Avoid log(0) instabilities.
power_db = log10(lib.maximum(amin, amplitude))
power_db *= 20.0
# Perceptual weighting.
frequencies = librosa.fft_frequencies(sr=sample_rate, n_fft=n_fft)
a_weighting = librosa.A_weighting(frequencies)[lib.newaxis, lib.newaxis, :]
loudness = power_db + a_weighting
# Set dynamic range.
loudness -= ref_db
loudness = lib.maximum(loudness, -range_db)
mean = tf.reduce_mean if use_tf else np.mean
# Average over frequency bins.
loudness = mean(loudness, axis=-1)
# Remove temporary batch dimension.
loudness = loudness[0] if is_1d else loudness
return loudness
def get_spectrogram(audio, rotate=False, size=1024):
"""Compute logmag spectrogram."""
mag = ddsp.spectral_ops.compute_logmag(tf_float32(audio), size=size)
if rotate:
mag = np.rot90(mag)
return mag
def additive_synthesis(self,
amplitudes,
frequency_shifts=None,
frequency_distribution=None,
n_samples=64000,
sample_rate=16000,
amp_resample_method="window"):
'''Generate audio from frame-wise monophonic harmonic oscillator bank.
Args:
amplitudes: Frame-wise oscillator peak amplitude. Shape [batch_size,
n_frames, 1].
frequency_shifts: Harmonic frequency variations (Hz), zero-centered. Total
frequency of a harmonic is equal to (frequencies * (1 +
frequency_shifts)). Shape [batch_size, n_frames, n_harmonics].
frequency_distribution: Harmonic amplitude variations, ranged zero to one.
Total amplitude of a harmonic is equal to (amplitudes *
frequency_distribution). Shape [batch_size, n_frames, n_harmonics].
n_samples: Total length of output audio. Interpolates and crops to this.
sample_rate: Sample rate.
amp_resample_method: Mode with which to resample amplitude envelopes.
Returns:
audio: Output audio. Shape [batch_size, n_samples, 1]
'''
amplitudes = core.tf_float32(amplitudes)
batch_size = amplitudes.shape[0]
n_frames = amplitudes.shape[1]
if frequency_distribution is not None:
frequency_distribution = core.tf_float32(frequency_distribution)
n_frequencies = int(frequency_distribution.shape[-1])
elif harmonic_shifts is not None:
harmonic_shifts = core.tf_float32(harmonic_shifts)
n_frequencies = int(frequency_shifts.shape[-1])
else:
n_frequencies = 1
# Create frequencies [batch_size, n_frames, n_frequencies].
frequencies = self.get_linear_frequencies(batch_size, n_frames,
n_frequencies)
if frequency_shifts is not None:
frequencies *= (1.0 + harmonic_shifts)
# Create harmonic amplitudes [batch_size, n_frames, n_frequencies].
if frequency_distribution is not None:
frequency_amplitudes = amplitudes * frequency_distribution
else:
frequency_amplitudes = amplitudes
# Create sample-wise envelopes.
frequency_envelopes = core.resample(frequencies,
n_samples) # cycles/sec
amplitude_envelopes = core.resample(frequency_amplitudes,
n_samples,
method=amp_resample_method)
# Synthesize from harmonics [batch_size, n_samples].
audio = core.oscillator_bank(frequency_envelopes,
amplitude_envelopes,
sample_rate=sample_rate)
return audio
def compute_loudness(audio,
sample_rate=16000,
frame_rate=250,
n_fft=512,
range_db=DB_RANGE,
ref_db=0.0,
use_tf=True,
pad_end=True):
"""Perceptual loudness (weighted power) in dB.
Function is differentiable if use_tf=True.
Args:
audio: Numpy ndarray or tensor. Shape [batch_size, audio_length] or
[batch_size,].
sample_rate: Audio sample rate in Hz.
frame_rate: Rate of loudness frames in Hz.
n_fft: Fft window size.
range_db: Sets the dynamic range of loudness in decibles. The minimum
loudness (per a frequency bin) corresponds to -range_db.
ref_db: Sets the reference maximum perceptual loudness as given by
(A_weighting + 10 * log10(abs(stft(audio))**2.0). The old (<v2.0.0)
default value corresponded to white noise with amplitude=1.0 and
n_fft=2048. With v2.0.0 it was set to 0.0 to be more consistent with power
calculations that have a natural scale for 0 dB being amplitude=1.0.
use_tf: Make function differentiable by using tensorflow.
pad_end: Add zero padding at end of audio (like `same` convolution).
Returns:
Loudness in decibels. Shape [batch_size, n_frames] or [n_frames,].
"""
if sample_rate % frame_rate != 0:
raise ValueError(
'frame_rate: {} must evenly divide sample_rate: {}.'
'For default frame_rate: 250Hz, suggested sample_rate: 16kHz or 48kHz'
.format(frame_rate, sample_rate))
# Pick tensorflow or numpy.
lib = tf if use_tf else np
reduce_mean = tf.reduce_mean if use_tf else np.mean
stft_fn = stft if use_tf else stft_np
# Make inputs tensors for tensorflow.
audio = tf_float32(audio) if use_tf else audio
# Temporarily a batch dimension for single examples.
is_1d = (len(audio.shape) == 1)
audio = audio[lib.newaxis, :] if is_1d else audio
# Take STFT.
hop_size = sample_rate // frame_rate
overlap = 1 - hop_size / n_fft
s = stft_fn(audio, frame_size=n_fft, overlap=overlap, pad_end=pad_end)
# Compute power.
amplitude = lib.abs(s)
power = amplitude**2
# Perceptual weighting.
frequencies = librosa.fft_frequencies(sr=sample_rate, n_fft=n_fft)
a_weighting = librosa.A_weighting(frequencies)[lib.newaxis, lib.newaxis, :]
# Perform weighting in linear scale, a_weighting given in decibels.
weighting = 10**(a_weighting / 10)
power = power * weighting
# Average over frequencies (weighted power per a bin).
avg_power = reduce_mean(power, axis=-1)
loudness = core.power_to_db(avg_power,
ref_db=ref_db,
range_db=range_db,
use_tf=use_tf)
# Remove temporary batch dimension.
loudness = loudness[0] if is_1d else loudness
# Compute expected length of loudness vector.
expected_secs = audio.shape[-1] / float(sample_rate)
expected_len = int(expected_secs * frame_rate)
# Pad with `-range_db` noise floor or trim vector.
loudness = pad_or_trim_to_expected_length(loudness,
expected_len,
-range_db,
use_tf=use_tf)
return loudness
def call(self, audio, target_audio): audio, target_audio = tf_float32(audio), tf_float32(target_audio) target_emb = self.pretrained_model(target_audio) synth_emb = self.pretrained_model(audio) loss = self.weight * mean_difference(target_emb, synth_emb, self.loss_type) return loss