2026-09-21 09:04:44 +07:00

149 lines
4.9 KiB
Python

"""
Tugas No. 4 - Implementasi CNN sederhana untuk MNIST
dan perbandingannya dengan MLP dari Tugas No. 1.
"""
import os
import sys
import time
# Sembunyikan log informasi TensorFlow
os.environ["TF_CPP_MIN_LOG_LEVEL"] = "2"
import matplotlib
matplotlib.use("Agg") # simpan plot sebagai file
import matplotlib.pyplot as plt
import numpy as np
import tensorflow as tf
# Tambahkan root directory ke path agar dapat import dari src
sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), "..")))
from src.data_loader import load_mnist_for_cnn
from src.models import create_cnn_mnist_model
from src.utils import EpochTimerCallback, ensure_dir
def main():
# Konfigurasi
SEED = 42
EPOCHS = 10
BATCH_SIZE = 128
VAL_SPLIT = 0.1
tf.random.set_seed(SEED)
np.random.seed(SEED)
# Hasil MLP terbaik dari Tugas No. 1 (Model C: 256-128-64)
MLP_ACCURACY = 0.9764
MLP_PARAMS = 242_762
MLP_EPOCH_TIME = 2.50
# 1. Load dan preprocessing data
print("Memuat dataset MNIST untuk CNN...")
(x_train, y_train), (x_test, y_test) = load_mnist_for_cnn()
print(f"Data training : {x_train.shape[0]:,} gambar")
print(f"Data testing : {x_test.shape[0]:,} gambar")
print(f"Ukuran gambar : {x_train.shape[1]} x {x_train.shape[2]} piksel (channel={x_train.shape[3]})\n")
# 2. Bangun model CNN
model = create_cnn_mnist_model()
model.summary()
# 3. Training dengan pencatatan waktu per epoch
timer_cb = EpochTimerCallback()
print("\nMemulai training CNN...")
print("Perkiraan waktu: 15-20 detik per epoch di CPU (total sekitar 3 menit).\n")
history = model.fit(
x_train,
y_train,
validation_split=VAL_SPLIT,
epochs=EPOCHS,
batch_size=BATCH_SIZE,
verbose=2,
callbacks=[timer_cb],
)
# 4. Evaluasi
test_loss, test_acc = model.evaluate(x_test, y_test, verbose=0)
n_params = model.count_params()
avg_epoch_time = float(np.mean(timer_cb.epoch_times)) if timer_cb.epoch_times else 0.0
predictions = np.argmax(model.predict(x_test, verbose=0), axis=1)
n_wrong = int(np.sum(predictions != y_test))
# 5. Perbandingan CNN vs MLP
error_mlp = (1 - MLP_ACCURACY) * 100
error_cnn = (1 - test_acc) * 100
gain_point = (test_acc - MLP_ACCURACY) * 100
error_reduction = (1 - error_cnn / error_mlp) * 100
print("\n" + "=" * 62)
print("HASIL EKSPERIMEN CNN")
print("=" * 62)
print(f"Test accuracy : {test_acc * 100:.2f}%")
print(f"Test loss : {test_loss:.4f}")
print(f"Jumlah parameter : {n_params:,}")
print(f"Waktu training/epoch : {avg_epoch_time:.2f} detik")
print(f"Salah klasifikasi : {n_wrong} dari {len(y_test):,} gambar")
print("\n" + "=" * 62)
print("PERBANDINGAN CNN vs MLP")
print("=" * 62)
print(f"{'Metrik':<24}{'MLP':>14}{'CNN':>14}")
print("-" * 62)
print(f"{'Test accuracy':<24}{MLP_ACCURACY * 100:>13.2f}%{test_acc * 100:>13.2f}%")
print(f"{'Error rate':<24}{error_mlp:>13.2f}%{error_cnn:>13.2f}%")
print(f"{'Jumlah parameter':<24}{MLP_PARAMS:>14,}{n_params:>14,}")
print(f"{'Waktu/epoch (detik)':<24}{MLP_EPOCH_TIME:>14.2f}{avg_epoch_time:>14.2f}")
print("-" * 62)
print(f"Improvement akurasi : +{gain_point:.2f} poin persentase")
print(f"Pengurangan error rate : {error_reduction:.1f}% (relatif)")
print(f"Selisih parameter : {n_params - MLP_PARAMS:+,}")
print("=" * 62)
# 6. Simpan grafik ke folder results/figures
results_fig_dir = os.path.join("results", "figures")
ensure_dir(results_fig_dir)
fig_path = os.path.join(results_fig_dir, "hasil_cnn.png")
fig, axes = plt.subplots(1, 2, figsize=(12, 4.5))
epochs_range = range(1, EPOCHS + 1)
axes[0].plot(epochs_range, history.history["accuracy"], label="Train accuracy")
axes[0].plot(epochs_range, history.history["val_accuracy"], label="Validation accuracy")
axes[0].set_title("Learning Curve CNN")
axes[0].set_xlabel("Epoch")
axes[0].set_ylabel("Accuracy")
axes[0].legend()
axes[0].grid(alpha=0.3)
axes[1].bar(
["MLP terbaik", "CNN"],
[MLP_ACCURACY * 100, test_acc * 100],
color=["#55A868", "#C44E52"],
)
axes[1].set_ylim(96, 100)
axes[1].set_ylabel("Test Accuracy (%)")
axes[1].set_title("Perbandingan MLP vs CNN")
for i, value in enumerate([MLP_ACCURACY * 100, test_acc * 100]):
axes[1].text(i, value + 0.05, f"{value:.2f}%", ha="center")
plt.tight_layout()
plt.savefig(fig_path, dpi=130)
print(f"\n[INFO] Grafik disimpan di: {fig_path}")
# 7. Simpan model terlatih ke folder results/models
results_model_dir = os.path.join("results", "models")
ensure_dir(results_model_dir)
model_path = os.path.join(results_model_dir, "model_cnn_mnist.keras")
model.save(model_path)
print(f"[INFO] Model disimpan di: {model_path}")
if __name__ == "__main__":
main()