EMG_Biometrics_2021/Neural_Network_Analysis.py

338 lines
14 KiB
Python

import json
from python_speech_features.python_speech_features.base import mfcc
import numpy as np
from sklearn.model_selection import train_test_split
import tensorflow as tf
import tensorflow.keras as keras
from keras import backend as K
from keras.regularizers import l2
from pathlib import Path
import pandas as pd
import matplotlib.pyplot as plt
import statistics
# Path to json file that stores MFCCs and subject labels for each processed sample
DATA_PATH_MFCC = str(Path.cwd()) + "/mfcc_data.json"
# Loads data from the json file and reshapes X_data(samples, 1, 208) and y_data(samples, 1)
# Input: JSON path
# Ouput: X(mfcc data), y(labels), session_lengths
def load_data_from_json(data_path, nr_classes):
with open(data_path, "r") as fp:
data = json.load(fp)
# Convert lists to numpy arrays and reshapes them
X = np.array(data['mfcc'])
X = X.reshape(X.shape[0], 1, X.shape[1])
y = np.array(data["labels"])
y = keras.utils.to_categorical(y, nr_classes)
session_lengths = np.array(data['session_lengths'])
print("Data succesfully loaded!")
return X, y, session_lengths
# Plots the training history with two subplots. First training and test accuracy, and then
# loss with respect to epochs
# Input: History(from model.fit(...))
# Ouput: None -> plot
def plot_train_history(history, val_data=False):
fig, axs = plt.subplots(2)
# create accuracy sublpot
axs[0].plot(history.history["accuracy"], label="train accuracy")
if val_data:
axs[0].plot(history.history["val_accuracy"], label="validation accuracy")
axs[0].set_ylabel("Accuracy")
axs[0].legend(loc="lower right")
axs[0].set_title("Accuracy eval")
# create error sublpot
axs[1].plot(history.history["loss"], label="train error")
if val_data:
axs[1].plot(history.history["val_loss"], label="validation error")
axs[1].set_ylabel("Error")
axs[1].set_xlabel("Epoch")
axs[1].legend(loc="upper right")
axs[1].set_title("Error eval")
plt.show()
# Takes in data and labels, and splits it into train, validation and test sets by percentage
# Input: Data, labels, whether to shuffle, % validatiion, % test
# Ouput: X_train, X_validation, X_test, y_train, y_validation, y_test
def prepare_datasets_percentsplit(X, y, shuffle_vars, validation_size=0.2, test_size=0.25,):
# Create train, validation and test split
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=test_size, shuffle=shuffle_vars)
X_train, X_validation, y_train, y_validation = train_test_split(X_train, y_train, test_size=validation_size, shuffle=shuffle_vars)
return X_train, X_validation, X_test, y_train, y_validation, y_test
# Takes in data, labels, and session_lengths and splits it into train and test sets by session_index
# Input: Data, labels, session_lengths, test_session_index
# Ouput: X_train, X_test, y_train, y_test
def prepare_datasets_sessions(X, y, session_lengths, test_session_index=4, nr_subjects=5):
session_lengths = session_lengths.tolist()
subject_starting_index = 0
start_test_index = subject_starting_index + sum(session_lengths[0][:test_session_index-1])
end_test_index = start_test_index + session_lengths[0][test_session_index-1]
end_subject_index = subject_starting_index + sum(session_lengths[0])
# Testing to check correctly slicing
'''
print(session_lengths[0], 'Sum:', sum(session_lengths[0]))
print('Subject start:', subject_starting_index)
print('Test start:', start_test_index)
print('Test end:', end_test_index)
print('Subject end:', end_subject_index, '\n -------')
'''
if start_test_index == subject_starting_index:
X_test = X[start_test_index:end_test_index]
y_test = y[start_test_index:end_test_index]
X_train = X[end_test_index:end_subject_index]
y_train = y[end_test_index:end_subject_index]
elif end_test_index == end_subject_index:
#print(X[subject_starting_index:start_test_index].shape)
X_train = X[subject_starting_index:start_test_index]
y_train = y[subject_starting_index:start_test_index]
X_test = X[start_test_index:end_test_index]
#print(X[start_test_index:end_test_index].shape, '\n ---')
y_test = y[start_test_index:end_test_index]
else:
X_train = X[subject_starting_index:start_test_index]
y_train = y[subject_starting_index:start_test_index]
X_test = X[start_test_index:end_test_index]
y_test = y[start_test_index:end_test_index]
X_train = np.concatenate((X_train, X[end_test_index:end_subject_index]))
y_train = np.concatenate((y_train, y[end_test_index:end_subject_index]))
#print(X_train.shape, '\n -------')
subject_starting_index = max(end_subject_index, end_test_index)
for i in range(1, nr_subjects):
start_test_index = subject_starting_index + sum(session_lengths[i][:test_session_index-1])
end_test_index = start_test_index + session_lengths[i][test_session_index-1]
end_subject_index = subject_starting_index + sum(session_lengths[i])
# Testing to check correctly slicing
'''
print(session_lengths[i], 'Sum:', sum(session_lengths[i]))
print('Subject start:', subject_starting_index)
print('Test start:', start_test_index)
print('Test end:', end_test_index)
print('Subject end:', end_subject_index, '\n -------')
'''
if start_test_index == subject_starting_index:
X_test = np.concatenate((X_test, X[start_test_index:end_test_index]))
y_test = np.concatenate((y_test, y[start_test_index:end_test_index]))
X_train = np.concatenate((X_train, X[end_test_index:end_subject_index]))
y_train = np.concatenate((y_train, y[end_test_index:end_subject_index]))
elif end_test_index == end_subject_index:
#print(X[subject_starting_index:start_test_index].shape)
X_train = np.concatenate((X_train, X[subject_starting_index:start_test_index]))
y_train = np.concatenate((y_train, y[subject_starting_index:start_test_index]))
#print(X[start_test_index:end_test_index].shape, '\n ---')
X_test = np.concatenate((X_test, X[start_test_index:end_test_index]))
y_test = np.concatenate((y_test, y[start_test_index:end_test_index]))
else:
X_train = np.concatenate((X_train, X[subject_starting_index:start_test_index]))
y_train = np.concatenate((y_train, y[subject_starting_index:start_test_index]))
X_test = np.concatenate((X_test, X[start_test_index:end_test_index]))
y_test = np.concatenate((y_test, y[start_test_index:end_test_index]))
X_train = np.concatenate((X_train, X[end_test_index:end_subject_index]))
y_train = np.concatenate((y_train, y[end_test_index:end_subject_index]))
#print(X_train.shape, '\n -------')
subject_starting_index = max(end_subject_index, end_test_index)
return X_train, X_test, y_train, y_test
# Trains the model
# Input: Keras.model, batch_size, nr epochs, training, and validation data
# Ouput: History
def train(model, X_train, y_train, verbose, batch_size=64, epochs=30, X_validation=None, y_validation=None):
optimiser = keras.optimizers.Adam(learning_rate=0.0001)
model.compile(optimizer=optimiser,
loss='categorical_crossentropy',
metrics=['accuracy'])
if X_validation != None:
history = model.fit(X_train,
y_train,
validation_data=(X_validation, y_validation),
batch_size=batch_size,
epochs=epochs,
verbose=verbose)
else:
history = model.fit(X_train,
y_train,
batch_size=batch_size,
epochs=epochs,
verbose=verbose)
return history
# Gives nr of datapoints for chosen session
# Input: session_lengths 2d-list, session_nr, nr of subjects
# Ouput: int(datapoints)
def get_nr_in_session(session_lengths:list, session_nr, nr_subjects=5):
summ = 0
for i in range(nr_subjects):
summ += session_lengths[i][session_nr-1]
return summ
# Prints session and training data
# Input: None
# Ouput: None -> print
def print_session_train_data(X_train, X_test, y_train, y_test, session_lengths, session_nr):
print(X_train.size)
print(X_train.shape)
print(X_test.shape)
print(y_train.shape)
print(y_test.shape)
print('Datapoints in session ' + str(session_nr) + ':', get_nr_in_session(session_lengths, session_nr))
print('Should be remaining:', 2806 - get_nr_in_session(session_lengths, session_nr))
# Reshapes training og test data into batches NOT RELEVANT?
# Input: training, test data (and validation), batch_size
# Ouput: training, test data (and validation)
def batch_formatting(X_train, X_test, y_train, y_test, batch_size=64, nr_classes=5, X_validation=None, y_validation=None):
train_splits = X_train.shape[0] // batch_size
train_rest = X_train.shape[0] % batch_size
test_splits = X_test.shape[0] // batch_size
test_rest = X_test.shape[0] % batch_size
X_train = X_train[:-train_rest]
y_train = y_train[:-train_rest]
X_test = X_test[:-test_rest]
y_test = y_test[:-test_rest]
X_train_batch = np.reshape(X_train, (batch_size, train_splits, 208))
y_train_batch = np.reshape(y_train, (batch_size, train_splits, nr_classes))
X_test_batch = np.reshape(X_test, (batch_size, test_splits, 208))
y_test_batch = np.reshape(y_test, (batch_size, test_splits, nr_classes))
if X_validation != None:
val_splits = X_validation.shape[0] // batch_size
val_rest = X_validation.shape[0] % batch_size
X_validation = X_validation[:-val_rest]
y_validation = y_validation[:-val_rest]
X_val_batch = np.reshape(X_validation, (batch_size, val_splits, 208))
y_val_batch = np.reshape(y_validation, (batch_size, val_splits))
return X_train_batch, X_test_batch, y_train_batch, y_test_batch, X_val_batch, y_val_batch
return X_train_batch, X_test_batch, y_train_batch, y_test_batch
# Retrieves data sets for each session as test set and evalutes
# the average of networks trained om them
# Input: raw data, session_lengths list, total nr of sessions, batch_size, and nr of epochs
# Ouput: tuple(cross validation average, list(result for each dataset(len=nr_sessions)))
def session_cross_validation_LSTM(X, y, session_lengths, nr_sessions, batch_size=64, epochs=30):
session_training_results = []
for i in range(nr_sessions):
model = LSTM(input_shape=(1, 208))
X_train_session, X_test_session, y_train_session, y_test_session = prepare_datasets_sessions(X, y, session_lengths, i)
train(model, X_train_session, y_train_session, verbose=0, batch_size=batch_size, epochs=epochs)
test_loss, test_acc = model.evaluate(X_test_session, y_test_session, verbose=2)
session_training_results.append(test_acc)
del model
K.clear_session()
print('Session', i, 'as test data gives accuracy:', test_acc)
average_result = statistics.mean((session_training_results))
return average_result, session_training_results
# ----- MODELS ------
# Creates a keras.model with focus on LSTM layers
# Input: input shape, classes of classification
# Ouput: model:Keras.model
def LSTM(input_shape, nr_classes=5):
model = keras.Sequential()
model.add(keras.layers.Bidirectional(keras.layers.LSTM(64), input_shape=input_shape, name='Bidirectional_LSTM'))
model.add(keras.layers.Dense(64, activation='relu', activity_regularizer=l2(0.001), name='Dense_relu'))
model.add(keras.layers.Dropout(0.3, name='Dropout'))
# Output layer
model.add(keras.layers.Dense(nr_classes, activation='softmax', name='Dense_relu_output'))
return model
# Creates a keras.model with focus on GRU layers
# Input: input shape, classes of classification
# Ouput: model:Keras.model
def GRU(input_shape, nr_classes=5):
model = keras.Sequential()
model.add(keras.layers.Bidirectional(keras.layers.GRU(64), input_shape=input_shape, name='Bidirectional_GRU'))
model.add(keras.layers.Dense(64, activation='relu', activity_regularizer=l2(0.001), name='Dense_relu'))
model.add(keras.layers.Dropout(0.3, name='Dropout'))
# Output layer:
model.add(keras.layers.Dense(nr_classes, activation='softmax', name='Dense_relu_output'))
return model
if __name__ == "__main__":
# ----- Load data ------
# X.shape = (2806, 1, 208)
# y.shape = (2806, nr_subjects)
# session_lengths.shape = (nr_subjects, nr_sessions)
X, y, session_lengths = load_data_from_json(DATA_PATH_MFCC, nr_classes=5)
# Parameters:
NR_SUBJECTS = 5
NR_SESSIONS = 4
BATCH_SIZE = 64
EPOCHS = 30
TEST_SESSION_NR = 4
VERBOSE = 0
# ----- Get prepared data: train, validation, and test ------
# X_train.shape = (2806-X_test, 1, 208)
# X_test.shape = (X_test(from session nr. ?), 1, 208)
# y_train.shape = (2806-y_test, nr_subjects)
# y_test.shape = (y_test(from session nr. ?), nr_subjects)
X_train, X_test, y_train, y_test = prepare_datasets_sessions(X, y, session_lengths, TEST_SESSION_NR)
#'''
# ----- Make model ------
model_GRU = GRU(input_shape=(1, 208)) # (timestep, 13*16 MFCC coefficients)
model_LSTM = LSTM(input_shape=(1, 208)) # (timestep, 13*16 MFCC coefficients)
model_GRU.summary()
model_LSTM.summary()
# ----- Train network ------
history_GRU = train(model_GRU, X_train, y_train, verbose=VERBOSE, batch_size=BATCH_SIZE, epochs=EPOCHS)
history_LSTM = train(model_LSTM, X_train, y_train, verbose=VERBOSE, batch_size=BATCH_SIZE, epochs=EPOCHS)
#average = session_cross_validation_LSTM(X, y, session_lengths, NR_SESSIONS, BATCH_SIZE, EPOCHS)
#print('\nCrossvalidated:', average)
# ----- Plot train accuracy/error -----
#plot_train_history(history)
# ----- Evaluate model on test set ------
test_loss, test_acc = model_GRU.evaluate(X_test, y_test, verbose=VERBOSE)
print('\nTest accuracy GRU:', test_acc, '\n')
test_loss, test_acc = model_LSTM.evaluate(X_test, y_test, verbose=VERBOSE)
print('\nTest accuracy LSTM:', test_acc, '\n')
#'''