import tensorflow as tf
from tensorflow import keras
from TTS.tf.utils.tf_utils import shape_list
from TTS.tf.layers.common_layers import Prenet, Attention
# from tensorflow_addons.seq2seq import AttentionWrapper
class ConvBNBlock(keras.layers.Layer):
def __init__(self, filters, kernel_size, activation, **kwargs):
super(ConvBNBlock, self).__init__(**kwargs)
self.convolution1d = keras.layers.Conv1D(filters, kernel_size, padding='same', name='convolution1d')
self.batch_normalization = keras.layers.BatchNormalization(axis=2, momentum=0.90, epsilon=1e-5, name='batch_normalization')
self.dropout = keras.layers.Dropout(rate=0.5, name='dropout')
self.activation = keras.layers.Activation(activation, name='activation')
def call(self, x, training=None):
o = self.convolution1d(x)
o = self.batch_normalization(o, training=training)
o = self.activation(o)
o = self.dropout(o, training=training)
return o
class Postnet(keras.layers.Layer):
def __init__(self, output_filters, num_convs, **kwargs):
super(Postnet, self).__init__(**kwargs)
self.convolutions = []
self.convolutions.append(ConvBNBlock(512, 5, 'tanh', name='convolutions_0'))
for idx in range(1, num_convs - 1):
self.convolutions.append(ConvBNBlock(512, 5, 'tanh', name=f'convolutions_{idx}'))
self.convolutions.append(ConvBNBlock(output_filters, 5, 'linear', name=f'convolutions_{idx+1}'))
def call(self, x, training=None):
o = x
for layer in self.convolutions:
o = layer(o, training=training)
return o
class Encoder(keras.layers.Layer):
def __init__(self, output_input_dim, **kwargs):
super(Encoder, self).__init__(**kwargs)
self.convolutions = []
for idx in range(3):
self.convolutions.append(ConvBNBlock(output_input_dim, 5, 'relu', name=f'convolutions_{idx}'))
self.lstm = keras.layers.Bidirectional(keras.layers.LSTM(output_input_dim // 2, return_sequences=True, use_bias=True), name='lstm')
def call(self, x, training=None):
o = x
for layer in self.convolutions:
o = layer(o, training=training)
o = self.lstm(o)
return o
class Decoder(keras.layers.Layer):
#pylint: disable=unused-argument
def __init__(self, frame_dim, r, attn_type, use_attn_win, attn_norm, prenet_type,
prenet_dropout, use_forward_attn, use_trans_agent, use_forward_attn_mask,
use_location_attn, attn_K, separate_stopnet, speaker_emb_dim, **kwargs):
super(Decoder, self).__init__(**kwargs)
self.frame_dim = frame_dim
self.r_init = tf.constant(r, dtype=tf.int32)
self.r = tf.constant(r, dtype=tf.int32)
self.separate_stopnet = separate_stopnet
self.max_decoder_steps = tf.constant(1000, dtype=tf.int32)
self.stop_thresh = tf.constant(0.5, dtype=tf.float32)
# model dimensions
self.query_dim = 1024
self.decoder_rnn_dim = 1024
self.prenet_dim = 256
self.attn_dim = 128
self.p_attention_dropout = 0.1
self.p_decoder_dropout = 0.1
self.prenet = Prenet(prenet_type,
prenet_dropout,
[self.prenet_dim, self.prenet_dim],
bias=False,
name='prenet')
self.attention_rnn = keras.layers.LSTMCell(self.query_dim, use_bias=True, name=f'{self.name}/attention_rnn', )
self.attention_rnn_dropout = keras.layers.Dropout(0.5)
# TODO: implement other attn options
self.attention = Attention(attn_dim=self.attn_dim,
use_loc_attn=True,
loc_attn_n_filters=32,
loc_attn_kernel_size=31,
use_windowing=False,
norm=attn_norm,
use_forward_attn=use_forward_attn,
use_trans_agent=use_trans_agent,
use_forward_attn_mask=use_forward_attn_mask,
name='attention')
self.decoder_rnn = keras.layers.LSTMCell(self.decoder_rnn_dim, use_bias=True, name=f'{self.name}/decoder_rnn')
self.decoder_rnn_dropout = keras.layers.Dropout(0.5)
self.linear_projection = keras.layers.Dense(self.frame_dim * r, name=f'{self.name}/linear_projection/linear_layer')
self.stopnet = keras.layers.Dense(1, name=f'{self.name}/stopnet/linear_layer')
def set_max_decoder_steps(self, new_max_steps):
self.max_decoder_steps = tf.constant(new_max_steps, dtype=tf.int32)
def set_r(self, new_r):
self.r = tf.constant(new_r, dtype=tf.int32)
def build_decoder_initial_states(self, batch_size, memory_dim, memory_length):
zero_frame = tf.zeros([batch_size, self.frame_dim])
zero_context = tf.zeros([batch_size, memory_dim])
attention_rnn_state = self.attention_rnn.get_initial_state(batch_size=batch_size, dtype=tf.float32)
decoder_rnn_state = self.decoder_rnn.get_initial_state(batch_size=batch_size, dtype=tf.float32)
attention_states = self.attention.init_states(batch_size, memory_length)
return zero_frame, zero_context, attention_rnn_state, decoder_rnn_state, attention_states
def step(self, prenet_next, states,
memory_seq_length=None, training=None):
_, context_next, attention_rnn_state, decoder_rnn_state, attention_states = states
attention_rnn_input = tf.concat([prenet_next, context_next], -1)
attention_rnn_output, attention_rnn_state = \
self.attention_rnn(attention_rnn_input,
attention_rnn_state, training=training)
attention_rnn_output = self.attention_rnn_dropout(attention_rnn_output, training=training)
context, attention, attention_states = self.attention(attention_rnn_output, attention_states, training=training)
decoder_rnn_input = tf.concat([attention_rnn_output, context], -1)
decoder_rnn_output, decoder_rnn_state = \
self.decoder_rnn(decoder_rnn_input, decoder_rnn_state, training=training)
decoder_rnn_output = self.decoder_rnn_dropout(decoder_rnn_output, training=training)
linear_projection_input = tf.concat([decoder_rnn_output, context], -1)
output_frame = self.linear_projection(linear_projection_input, training=training)
stopnet_input = tf.concat([decoder_rnn_output, output_frame], -1)
stopnet_output = self.stopnet(stopnet_input, training=training)
output_frame = output_frame[:, :self.r * self.frame_dim]
states = (output_frame[:, self.frame_dim * (self.r - 1):], context, attention_rnn_state, decoder_rnn_state, attention_states)
return output_frame, stopnet_output, states, attention
def decode(self, memory, states, frames, memory_seq_length=None):
B, _, _ = shape_list(memory)
num_iter = shape_list(frames)[1] // self.r
# init states
frame_zero = tf.expand_dims(states[0], 1)
frames = tf.concat([frame_zero, frames], axis=1)
outputs = tf.TensorArray(dtype=tf.float32, size=num_iter)
attentions = tf.TensorArray(dtype=tf.float32, size=num_iter)
stop_tokens = tf.TensorArray(dtype=tf.float32, size=num_iter)
# pre-computes
self.attention.process_values(memory)
prenet_output = self.prenet(frames, training=True)
step_count = tf.constant(0, dtype=tf.int32)
def _body(step, memory, prenet_output, states, outputs, stop_tokens, attentions):
prenet_next = prenet_output[:, step]
output, stop_token, states, attention = self.step(prenet_next,
states,
memory_seq_length)
outputs = outputs.write(step, output)
attentions = attentions.write(step, attention)
stop_tokens = stop_tokens.write(step, stop_token)
return step + 1, memory, prenet_output, states, outputs, stop_tokens, attentions
_, memory, _, states, outputs, stop_tokens, attentions = \
tf.while_loop(lambda *arg: True,
_body,
loop_vars=(step_count, memory, prenet_output,
states, outputs, stop_tokens, attentions),
parallel_iterations=32,
swap_memory=True,
maximum_iterations=num_iter)
outputs = outputs.stack()
attentions = attentions.stack()
stop_tokens = stop_tokens.stack()
outputs = tf.transpose(outputs, [1, 0, 2])
attentions = tf.transpose(attentions, [1, 0, 2])
stop_tokens = tf.transpose(stop_tokens, [1, 0, 2])
stop_tokens = tf.squeeze(stop_tokens, axis=2)
outputs = tf.reshape(outputs, [B, -1, self.frame_dim])
return outputs, stop_tokens, attentions
def decode_inference(self, memory, states):
B, _, _ = shape_list(memory)
# init states
outputs = tf.TensorArray(dtype=tf.float32, size=0, clear_after_read=False, dynamic_size=True)
attentions = tf.TensorArray(dtype=tf.float32, size=0, clear_after_read=False, dynamic_size=True)
stop_tokens = tf.TensorArray(dtype=tf.float32, size=0, clear_after_read=False, dynamic_size=True)
# pre-computes
self.attention.process_values(memory)
# iter vars
stop_flag = tf.constant(False, dtype=tf.bool)
step_count = tf.constant(0, dtype=tf.int32)
def _body(step, memory, states, outputs, stop_tokens, attentions, stop_flag):
frame_next = states[0]
prenet_next = self.prenet(frame_next, training=False)
output, stop_token, states, attention = self.step(prenet_next,
states,
None,
training=False)
stop_token = tf.math.sigmoid(stop_token)
outputs = outputs.write(step, output)
attentions = attentions.write(step, attention)
stop_tokens = stop_tokens.write(step, stop_token)
stop_flag = tf.greater(stop_token, self.stop_thresh)
stop_flag = tf.reduce_all(stop_flag)
return step + 1, memory, states, outputs, stop_tokens, attentions, stop_flag
cond = lambda step, m, s, o, st, a, stop_flag: tf.equal(stop_flag, tf.constant(False, dtype=tf.bool))
_, memory, states, outputs, stop_tokens, attentions, stop_flag = \
tf.while_loop(cond,
_body,
loop_vars=(step_count, memory, states, outputs,
stop_tokens, attentions, stop_flag),
parallel_iterations=32,
swap_memory=True,
maximum_iterations=self.max_decoder_steps)
outputs = outputs.stack()
attentions = attentions.stack()
stop_tokens = stop_tokens.stack()
outputs = tf.transpose(outputs, [1, 0, 2])
attentions = tf.transpose(attentions, [1, 0, 2])
stop_tokens = tf.transpose(stop_tokens, [1, 0, 2])
stop_tokens = tf.squeeze(stop_tokens, axis=2)
outputs = tf.reshape(outputs, [B, -1, self.frame_dim])
return outputs, stop_tokens, attentions
def call(self, memory, states, frames=None, memory_seq_length=None, training=False):
if training:
return self.decode(memory, states, frames, memory_seq_length)
return self.decode_inference(memory, states)