praca-magisterska/project/model.py

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Python
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2019-10-24 14:01:43 +02:00
from __future__ import print_function
from midi_processing import stream_to_bars
from keras.models import Model, load_model
from keras.layers import Input, LSTM, Dense, LSTM, LSTMCell, TimeDistributed
import numpy as np
class Seq2SeqTransformer():
''' encoder/transforer
params:
-------
x_train, y_train - list of sequences
methods:
fit
transform'''
def __init__(self):
self.transform_dict = None
self.reverse_dict = None
self.vocab_x = None
self.vocab_y = None
def preprocess(self, x_train, y_train):
'''Converts training set do list and add special chars'''
_x_train = []
for i, seq in enumerate(x_train):
_x_train.append([])
for note in seq:
_x_train[i].append(note)
_y_train = []
for i, seq in enumerate(y_train):
_y_train.append([])
_y_train[i].append('<GO>')
for note in seq:
_y_train[i].append(note)
_y_train[i].append('<EOS>')
return _x_train, _y_train
def transform(self, x_train, y_train):
x_vocab = set([note for seq in x_train for note in seq])
y_vocab = set([note for seq in y_train for note in seq])
self.x_vocab = sorted(list(x_vocab))
self.y_vocab = ['<GO>','<EOS>']
self.y_vocab.extend(sorted(list(y_vocab)))
self.x_vocab_size = len(self.x_vocab)
self.y_vocab_size = len(self.y_vocab)
self.x_transform_dict = dict(
[(char, i) for i, char in enumerate(self.x_vocab)])
self.y_transform_dict = dict(
[(char, i) for i, char in enumerate(self.y_vocab)])
self.x_reverse_dict = dict(
(i, char) for char, i in self.x_transform_dict.items())
self.y_reverse_dict = dict(
(i, char) for char, i in self.y_transform_dict.items())
x_train, y_train = self.preprocess(x_train, y_train)
self.x_max_seq_length = max([len(seq) for seq in x_train])
self.y_max_seq_length = max([len(seq) for seq in y_train])
encoder_input_data = np.zeros(
(len(x_train), self.x_max_seq_length, self.x_vocab_size),
dtype='float32')
decoder_input_data = np.zeros(
(len(x_train), self.y_max_seq_length, self.y_vocab_size),
dtype='float32')
decoder_target_data = np.zeros(
(len(x_train), self.y_max_seq_length, self.y_vocab_size),
dtype='float32')
for i, (x_train, y_train) in enumerate(zip(x_train, y_train)):
for t, char in enumerate(x_train):
encoder_input_data[i, t, self.x_transform_dict[char]] = 1.
for t, char in enumerate(y_train):
decoder_input_data[i, t, self.y_transform_dict[char]] = 1.
if t > 0:
decoder_target_data[i, t - 1, self.y_transform_dict[char]] = 1.
return encoder_input_data, decoder_input_data, decoder_target_data
class Seq2SeqModel():
'''NeuralNerwork Seq2Seq model.
The network is created based on training data
'''
def __init__(self, latent_dim, x_train, y_train):
self.has_predict_model = False
self.has_train_model = False
self.x_train = x_train
self.y_train = y_train
self.latent_dim = latent_dim
self.transformer = Seq2SeqTransformer()
self.encoder_input_data, self.decoder_input_data, self.decoder_target_data = self.transformer.transform(self.x_train, self.y_train)
# ---------------
# SEQ 2 SEQ MODEL:
# INPUT_1 : encoder_input_data
# INPUT_2 : decodet_input_data
# OUTPUT : decoder_target_data
# ---------------
# ENCODER MODEL
#---------------
# 1 layer - Input : encoder_input_data
self.encoder_inputs = Input(shape=(None, self.transformer.x_vocab_size ))
# 2 layer - LSTM_1, LSTM
self.encoder = LSTM(latent_dim, return_state=True)
#self.encoder = LSTM(latent_dim, return_state=True)
# 2 layer - LSTM_1 : outputs
self.encoder_outputs, self.state_h, self.state_c = self.encoder(self.encoder_inputs)
self.encoder_states = [self.state_h, self.state_c]
# DECODER MODEL
#---------------
# 1 layer - Input : decoder_input_data
self.decoder_inputs = Input(shape=(None, self.transformer.y_vocab_size))
# 2 layer - LSTM_1, LSTM
self.decoder_lstm = LSTM(latent_dim, return_sequences=True, return_state=True)
#self.decoder_lstm = LSTM(latent_dim, return_sequences=True, return_state=True)
# 2 layer - LSTM_2 : outputs, full sequance as lstm layer
self.decoder_outputs, _, _ = self.decoder_lstm(self.decoder_inputs,
initial_state=self.encoder_states)
# 3 layer - Dense
self.decoder_dense = Dense(self.transformer.y_vocab_size, activation='softmax')
# 3 layer - Dense : outputs, full sequance as the array of one-hot-encoded elements
self.decoder_outputs = self.decoder_dense(self.decoder_outputs)
def init_train_model(self):
self.train_model = Model([self.encoder_inputs, self.decoder_inputs], self.decoder_outputs)
self.train_model.compile(optimizer='rmsprop', loss='categorical_crossentropy')
def fit(self, batch_size, epochs, callbacks):
if not self.has_train_model:
self.init_train_model()
self.has_train_model = True
history = self.train_model.fit([self.encoder_input_data, self.decoder_input_data], self.decoder_target_data,
batch_size=batch_size,
epochs=epochs,
callbacks=callbacks,
validation_split=0.2)
return history
def save(self, path):
self.train_model.save(path)
def load(self, path):
self.train_model = load_model(path)
self.has_train_model = True
self.encoder_inputs = self.train_model.layers[0].input
self.encoder = self.train_model.layers[2]
self.encoder_outputs, self.state_h, self.state_c = self.train_model.layers[2].output
self.encoder_states = [self.state_h, self.state_c]
self.decoder_inputs = self.train_model.layers[1].input
self.decoder_lstm = self.train_model.layers[3]
self.decoder_outputs, _, _ = self.train_model.layers[3].output
self.decoder_dense = self.train_model.layers[4]
self.decoder_outputs = self.train_model.layers[4].output
def init_predict_model(self):
# ENCODER MODEL <- note used in develop music process
# from encoder_input to encoder_states
# to give a context to decoder model
#---------------------------------
self.encoder_model = Model(self.encoder_inputs, self.encoder_states)
# DECODER MODEL
# From states (context) to sequance by generating firts element from context vector
# and starting element <GO>. Then adding predicted element as input to next cell, with
# updated states (context) by prevously generated element.
#
# INPUT_1 : state_h
# INPUT_2 : state_c
# INPUT_3 : y_train sized layer, that will be recursivly generated starting from <GO> sign
#
# INPUT -> LSTM -> DENSE
#
# OUTPUT : one-hot-encoded element of sequance
# OUTPUT : state_h (updated)
# OUTPUT : state_c (updated)
# -------------
# 1 layer: TWO INPUTS: decoder_state_h, decoder_state_c
self.decoder_state_input_h = Input(shape=(self.latent_dim,))
self.decoder_state_input_c = Input(shape=(self.latent_dim,))
self.decoder_states_inputs = [self.decoder_state_input_h, self.decoder_state_input_c]
# 2 layer: LSTM_1 output: element of sequance, lstm cell states
self.decoder_outputs, self.state_h, self.state_c = self.decoder_lstm(
self.decoder_inputs,
initial_state = self.decoder_states_inputs
)
self.decoder_states = [self.state_h, self.state_c]
# 3 layer: Dense output: one-hot-encoded representation of element of sequance
self.decoder_outputs = self.decoder_dense(self.decoder_outputs)
self.decoder_model = Model(
[self.decoder_inputs] + self.decoder_states_inputs,
[self.decoder_outputs] + self.decoder_states)
self.has_predict_model = True
def predict(self, input_seq=None, mode=None):
if not self.has_predict_model:
self.init_predict_model()
self.has_predict_model = True
if mode == 'generate':
# create a random context as starting point
h = np.random.rand(1,self.latent_dim)*2 - 1
c = np.random.rand(1,self.latent_dim)*2 - 1
states_value = [h, c]
else:
# get context from input sequance
states_value = self.encoder_model.predict(input_seq)
# make the empty decoder_input_data
# and create the starting <GO> element of decoder_input_data
target_seq = np.zeros((1, 1, self.transformer.y_vocab_size))
target_seq[0, 0, self.transformer.y_transform_dict['<GO>']] = 1.
# sequance generation loop of decoder model
stop_condition = False
decoded_sentence = []
# time = 0
while not stop_condition:
# INPUT_1 : target_seq : started from empty array with start <GO> char
# and recursivly updated by predicted elements
# INPUT_2 : states_value :context from encoder model or randomly generated in develop mode
# this can give as a 2 * latent_dim parameters to play with in manual generation
# OUTPUT_1 : output_tokens : one hot encoded predicted element of sequance
# OUTPUT_2,3 : h, c : context updated by predicted element
output_tokens, h, c = self.decoder_model.predict(
[target_seq] + states_value)
# get most likly element index
# translate from index to final (in normal form) preidcted element
# append it to output list
sampled_token_index = np.argmax(output_tokens[0, -1, :])
sampled_char = self.transformer.y_reverse_dict[sampled_token_index]
decoded_sentence.append(sampled_char)
# time += sampled_char[1]
# or time>=16
if (sampled_char == '<EOS>' or len(decoded_sentence) > self.transformer.y_max_seq_length ):
stop_condition = True
target_seq = np.zeros((1, 1, self.transformer.y_vocab_size))
target_seq[0, 0, sampled_token_index] = 1.
states_value = [h, c]
return decoded_sentence
def develop(self, mode='from_seq'):
# music generation for seq2seq for melody
input_seq_start = random_seed_generator(16,
self.transformer.x_max_seq_length,
self.transformer.x_vocab_size,
self.transformer.x_transform_dict,
self.transformer.x_reverse_dict)
input_data = seq_to_numpy(input_seq_start,
self.transformer.x_max_seq_length,
self.transformer.x_vocab_size,
self.transformer.x_transform_dict)
# generate sequnce iterativly for melody
input_seq = input_seq_start.copy()
melody = []
for i in range(4):
if mode == 'from_seq':
decoded_sentence = self.predict(input_data)[:-1]
elif mode == 'from_state':
decoded_sentence = self.predict(mode='generate')[:-1]
else:
raise ValueError('mode must be in {from_seq, from_state}')
melody.append(decoded_sentence)
input_seq.extend(decoded_sentence)
input_bars = stream_to_bars(input_seq, 4)
input_bars = input_bars[1:5]
input_seq = [note for bar in input_bars for note in bar]
input_data = seq_to_numpy(input_seq,
self.transformer.x_max_seq_length,
self.transformer.x_vocab_size,
self.transformer.x_transform_dict)
melody = [note for bar in melody for note in bar]
return melody
def random_seed_generator(time_of_seq, max_encoder_seq_length, num_encoder_tokens, input_token_index, reverse_input_char_index):
time = 0
random_seq = []
items = 0
stop_sign = False
while (time < time_of_seq):
seed = np.random.randint(0,num_encoder_tokens-1)
note = reverse_input_char_index[seed]
time += note[1]
if time > time_of_seq:
note_time = note[1] - (time-time_of_seq)
trimmed_note = (note[0],note_time)
try:
seed = input_token_index[trimmed_note]
random_seq.append(trimmed_note)
items += 1
except KeyError:
time -= note[1]
continue
else:
random_seq.append(note)
items += 1
if items > max_encoder_seq_length:
time = 0
random_seq = []
items = 0
stop_sign = False
return random_seq
# seq to numpy array:
def seq_to_numpy(seq, max_encoder_seq_length, num_encoder_tokens, input_token_index):
input_data = np.zeros(
(1, max_encoder_seq_length, num_encoder_tokens),
dtype='float32')
for t, char in enumerate(seq):
try:
input_data[0, t, input_token_index[char]] = 1.
except KeyError:
char_time = char[1]
_char = ((-1,), char_time)
except IndexError:
break
return input_data