title: RAM Overflow Colab, when running model.fit() in Image Classifier of AutoKeras for many images
body: <p>I'm trying to create an Image Classifier on a dataset with 40'000 images, in order to let Autokeras train the most appropriate model for me afterwards. Now the problem is, that every time I load all the images and get their labels but when I run the normalization Google Colab, there is a RAM overflow (although having a Pro+ account). Subsequently my code:</p>
  <pre><code># Import TensorFlow
  %tensorflow_version 2.x
  import tensorflow as tf
  
  import keras
  from tensorflow.keras.preprocessing.image import ImageDataGenerator
  from tensorflow.keras.utils import normalize, to_categorical
  !pip install autokeras
  import autokeras as ak
  
  import glob
  import numpy as np
  
  images = glob.glob(path + '/*.png')
  
  import random
  
  data = []
  labels = []
  
  for i in images:
      image=tf.keras.preprocessing.image.load_img(i, color_mode='rgb')
      image=np.array(image, dtype ='float32')
      image=cv2.resize(image, (180, 180))
      image/=255.0
      data.append(image)
      label=os.path.basename(str(i.replace('.png', '')))
      label=label.split()[0]
      labels.append(label)
  
  data = np.array(data)
  labels = np.array(labels)
  print(labels)
  </code></pre>
  <p>Up until here everything works like a charm, but then I face the problem which creates the overflow:</p>
  <pre><code># normalize feature and encode label
  X = data 
  y = np.zeros(labels.shape)
  indices = np.unique(labels)
  for i in range(labels.shape[0]):
    y[i] = np.where(labels[i] == indices)[0]
  y = to_categorical(y)
  
  from sklearn.model_selection import train_test_split
  X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2,
                                                  random_state=42) # this line seems to be the problem where Colab has a RAM overflow
  
  clf= ak.ImageClassifier(overwrite=True, max_trials=20)
  clf.fit(X_train, y_train, epochs=10) # and also this line seems to be the problem where Colab has a RAM overflow.
  </code></pre>
  <p>Does anyone know what the problem might be? A hint in any direction would be highly appreciated, as this makes me going crazy!</p>