{"cells":[{"metadata":{"trusted":true},"cell_type":"code","source":"!pip install -q efficientnet\nimport efficientnet.tfkeras as efn\n\nimport math, re, os\nimport tensorflow as tf\nimport numpy as np\nimport pandas as pd\nimport matplotlib.pyplot as plt\nfrom kaggle_datasets import KaggleDatasets\nfrom tensorflow import keras\nfrom functools import partial\nfrom sklearn.model_selection import train_test_split\nfrom tensorflow.keras import models, layers\n\nprint(\"Tensorflow version \" + tf.__version__)","execution_count":null,"outputs":[]},{"metadata":{"trusted":true},"cell_type":"code","source":"try:\n    tpu = tf.distribute.cluster_resolver.TPUClusterResolver()\n    print('Device:', tpu.master())\n    tf.config.experimental_connect_to_cluster(tpu)\n    tf.tpu.experimental.initialize_tpu_system(tpu)\n    strategy = tf.distribute.experimental.TPUStrategy(tpu)\nexcept:\n    strategy = tf.distribute.get_strategy()\nprint('Number of replicas:', strategy.num_replicas_in_sync)","execution_count":null,"outputs":[]},{"metadata":{"trusted":true},"cell_type":"code","source":"AUTOTUNE = tf.data.experimental.AUTOTUNE\nGCS_PATH = KaggleDatasets().get_gcs_path()\nBATCH_SIZE = 16 * strategy.num_replicas_in_sync\nIMAGE_SIZE = [512, 512]\nCLASSES = ['0', '1', '2', '3', '4']\nEPOCHS = 25\nHEIGHT = 512\nWIDTH = 512\nCHANNELS = 3","execution_count":null,"outputs":[]},{"metadata":{},"cell_type":"markdown","source":"# Data augmentation\n"},{"metadata":{"trusted":true},"cell_type":"code","source":"def transform_rotation(image, height, rotation):\n    # input image - is one image of size [dim,dim,3] not a batch of [b,dim,dim,3]\n    # output - image randomly rotated\n    DIM = height\n    XDIM = DIM%2 #fix for size 331\n    \n    rotation = rotation * tf.random.uniform([1],dtype='float32')\n    # CONVERT DEGREES TO RADIANS\n    rotation = math.pi * rotation / 180.\n    \n    # ROTATION MATRIX\n    c1 = tf.math.cos(rotation)\n    s1 = tf.math.sin(rotation)\n    one = tf.constant([1],dtype='float32')\n    zero = tf.constant([0],dtype='float32')\n    rotation_matrix = tf.reshape(tf.concat([c1,s1,zero, -s1,c1,zero, zero,zero,one],axis=0),[3,3])\n\n    # LIST DESTINATION PIXEL INDICES\n    x = tf.repeat( tf.range(DIM//2,-DIM//2,-1), DIM )\n    y = tf.tile( tf.range(-DIM//2,DIM//2),[DIM] )\n    z = tf.ones([DIM*DIM],dtype='int32')\n    idx = tf.stack( [x,y,z] )\n    \n    # ROTATE DESTINATION PIXELS ONTO ORIGIN PIXELS\n    idx2 = K.dot(rotation_matrix,tf.cast(idx,dtype='float32'))\n    idx2 = K.cast(idx2,dtype='int32')\n    idx2 = K.clip(idx2,-DIM//2+XDIM+1,DIM//2)\n    \n    # FIND ORIGIN PIXEL VALUES \n    idx3 = tf.stack( [DIM//2-idx2[0,], DIM//2-1+idx2[1,]] )\n    d = tf.gather_nd(image, tf.transpose(idx3))\n        \n    return tf.reshape(d,[DIM,DIM,3])\n\ndef transform_shear(image, height, shear):\n    # input image - is one image of size [dim,dim,3] not a batch of [b,dim,dim,3]\n    # output - image randomly sheared\n    DIM = height\n    XDIM = DIM%2 #fix for size 331\n    \n    shear = shear * tf.random.uniform([1],dtype='float32')\n    shear = math.pi * shear / 180.\n        \n    # SHEAR MATRIX\n    one = tf.constant([1],dtype='float32')\n    zero = tf.constant([0],dtype='float32')\n    c2 = tf.math.cos(shear)\n    s2 = tf.math.sin(shear)\n    shear_matrix = tf.reshape(tf.concat([one,s2,zero, zero,c2,zero, zero,zero,one],axis=0),[3,3])    \n\n    # LIST DESTINATION PIXEL INDICES\n    x = tf.repeat( tf.range(DIM//2,-DIM//2,-1), DIM )\n    y = tf.tile( tf.range(-DIM//2,DIM//2),[DIM] )\n    z = tf.ones([DIM*DIM],dtype='int32')\n    idx = tf.stack( [x,y,z] )\n    \n    # ROTATE DESTINATION PIXELS ONTO ORIGIN PIXELS\n    idx2 = K.dot(shear_matrix,tf.cast(idx,dtype='float32'))\n    idx2 = K.cast(idx2,dtype='int32')\n    idx2 = K.clip(idx2,-DIM//2+XDIM+1,DIM//2)\n    \n    # FIND ORIGIN PIXEL VALUES \n    idx3 = tf.stack( [DIM//2-idx2[0,], DIM//2-1+idx2[1,]] )\n    d = tf.gather_nd(image, tf.transpose(idx3))\n        \n    return tf.reshape(d,[DIM,DIM,3])\n\ndef data_augment(image, label):\n    p_rotation = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    p_spatial = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    p_rotate = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    p_pixel_1 = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    p_pixel_2 = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    p_pixel_3 = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    p_shear = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    p_crop = tf.random.uniform([], 0, 1.0, dtype=tf.float32)\n    \n    # Shear\n    if p_shear > .2:\n        if p_shear > .6:\n            image = transform_shear(image, HEIGHT, shear=20.)\n        else:\n            image = transform_shear(image, HEIGHT, shear=-20.)\n            \n    # Rotation\n    if p_rotation > .2:\n        if p_rotation > .6:\n            image = transform_rotation(image, HEIGHT, rotation=45.)\n        else:\n            image = transform_rotation(image, HEIGHT, rotation=-45.)\n            \n    # Flips\n    image = tf.image.random_flip_left_right(image)\n    image = tf.image.random_flip_up_down(image)\n    if p_spatial > .75:\n        image = tf.image.transpose(image)\n        \n    # Rotates\n    if p_rotate > .75:\n        image = tf.image.rot90(image, k=3) # rotate 270º\n    elif p_rotate > .5:\n        image = tf.image.rot90(image, k=2) # rotate 180º\n    elif p_rotate > .25:\n        image = tf.image.rot90(image, k=1) # rotate 90º\n        \n    # Pixel-level transforms\n    if p_pixel_1 >= .4:\n        image = tf.image.random_saturation(image, lower=.7, upper=1.3)\n    if p_pixel_2 >= .4:\n        image = tf.image.random_contrast(image, lower=.8, upper=1.2)\n    if p_pixel_3 >= .4:\n        image = tf.image.random_brightness(image, max_delta=.1)\n        \n    # Crops\n    if p_crop > .7:\n        if p_crop > .9:\n            image = tf.image.central_crop(image, central_fraction=.6)\n        elif p_crop > .8:\n            image = tf.image.central_crop(image, central_fraction=.7)\n        else:\n            image = tf.image.central_crop(image, central_fraction=.8)\n    elif p_crop > .4:\n        crop_size = tf.random.uniform([], int(HEIGHT*.6), HEIGHT, dtype=tf.int32)\n        image = tf.image.random_crop(image, size=[crop_size, crop_size, CHANNELS])\n            \n    image = tf.image.resize(image, size=[HEIGHT, WIDTH])\n\n    return image, label","execution_count":null,"outputs":[]},{"metadata":{"trusted":true},"cell_type":"code","source":"def load_dataset(filenames, labeled=True, ordered=False):\n    ignore_order = tf.data.Options()\n    if not ordered:\n        ignore_order.experimental_deterministic = False # disable order, increase speed\n    dataset = tf.data.TFRecordDataset(filenames, num_parallel_reads=AUTOTUNE) # automatically interleaves reads from multiple files\n    dataset = dataset.with_options(ignore_order) # uses data as soon as it streams in, rather than in its original order\n    dataset = dataset.map(partial(read_tfrecord, labeled=labeled), num_parallel_calls=AUTOTUNE)\n    return dataset\n\n\nTRAINING_FILENAMES, VALID_FILENAMES = train_test_split(\n    tf.io.gfile.glob(GCS_PATH + '/train_tfrecords/ld_train*.tfrec'),\n    test_size=0.3, random_state=5\n)\n\nTEST_FILENAMES = tf.io.gfile.glob(GCS_PATH + '/test_tfrecords/ld_test*.tfrec')\n\n\ndef count_data_items(filenames):\n    n = [int(re.compile(r\"-([0-9]*)\\.\").search(filename).group(1)) for filename in filenames]\n    return np.sum(n)\n\nNUM_TRAINING_IMAGES = count_data_items(TRAINING_FILENAMES)\nNUM_VALIDATION_IMAGES = count_data_items(VALID_FILENAMES)\nNUM_TEST_IMAGES = count_data_items(TEST_FILENAMES)\n\nprint('Dataset: {} training images, {} validation images, {} (unlabeled) test images'.format(\n    NUM_TRAINING_IMAGES, NUM_VALIDATION_IMAGES, NUM_TEST_IMAGES))","execution_count":null,"outputs":[]},{"metadata":{},"cell_type":"markdown","source":"# getting data"},{"metadata":{"trusted":true},"cell_type":"code","source":"def get_training_dataset():\n    dataset = load_dataset(TRAINING_FILENAMES, labeled=True)  \n    dataset = dataset.map(data_augment, num_parallel_calls=AUTOTUNE)  \n    dataset = dataset.repeat()\n    dataset = dataset.shuffle(2048)\n    dataset = dataset.batch(BATCH_SIZE)\n    dataset = dataset.prefetch(AUTOTUNE)\n    return dataset\n\ndef get_validation_dataset(ordered=False):\n    dataset = load_dataset(VALID_FILENAMES, labeled=True, ordered=ordered) \n    dataset = dataset.batch(BATCH_SIZE)\n    dataset = dataset.cache()\n    dataset = dataset.prefetch(AUTOTUNE)\n    return dataset\n\ndef get_test_dataset(ordered=False):\n    dataset = load_dataset(TEST_FILENAMES, labeled=False, ordered=ordered)\n    dataset = dataset.batch(BATCH_SIZE)\n    dataset = dataset.prefetch(AUTOTUNE)\n    return dataset","execution_count":null,"outputs":[]},{"metadata":{},"cell_type":"markdown","source":"# Read tfrecord"},{"metadata":{"trusted":true},"cell_type":"code","source":"def decode_image(image):\n    image = tf.image.decode_jpeg(image, channels=3)\n    image = tf.cast(image, tf.float32) / 255.0\n    image = tf.reshape(image, [*IMAGE_SIZE, 3])\n    return image\n\ndef read_tfrecord(example, labeled):\n    tfrecord_format = {\n        \"image\": tf.io.FixedLenFeature([], tf.string),\n        \"target\": tf.io.FixedLenFeature([], tf.int64)\n    } if labeled else {\n        \"image\": tf.io.FixedLenFeature([], tf.string),\n        \"image_name\": tf.io.FixedLenFeature([], tf.string)\n    }\n    example = tf.io.parse_single_example(example, tfrecord_format)\n    image = decode_image(example['image'])\n    if labeled:\n        label = tf.cast(example['target'], tf.int32)\n        return image, label\n    idnum = example['image_name']\n    return image, idnum","execution_count":null,"outputs":[]},{"metadata":{},"cell_type":"markdown","source":"# Callbacks"},{"metadata":{"trusted":true},"cell_type":"code","source":"from keras.callbacks import ReduceLROnPlateau,EarlyStopping, ModelCheckpoint\n\n# Stop training when the validation loss metric has stopped decreasing for 5 epochs.\nearly_stopping = EarlyStopping(monitor = 'val_loss',\n                               patience = 2,\n                               mode = 'min',\n                               restore_best_weights = True)\n\n# Save the model with the minimum validation loss\ncheckpoint = ModelCheckpoint('best_model.hdf5', \n                             monitor = 'val_loss',\n                             verbose = 1,\n                             mode = 'min', \n                             save_best_only = True)\n# reduce learning rate\nreduce_lr = ReduceLROnPlateau(monitor = 'val_loss',\n                              factor = 0.2,\n                              patience = 3,\n                              min_lr = 0.001,\n                              mode = 'min',\n                              verbose = 1)\n","execution_count":null,"outputs":[]},{"metadata":{},"cell_type":"markdown","source":"# Model build"},{"metadata":{"trusted":true},"cell_type":"code","source":"with strategy.scope():\n    model = tf.keras.Sequential([\n        efn.EfficientNetB7(\n            input_shape=(*IMAGE_SIZE, 3),\n            weights='imagenet',\n            include_top=False\n        ),\n        layers.GlobalAveragePooling2D(),\n        layers.Dense(5, activation='sigmoid')\n    ])\n    \n    model.compile(\n        optimizer='adam',\n        loss='sparse_categorical_crossentropy',\n        metrics=['sparse_categorical_accuracy']\n    )\n    \n    model.summary()","execution_count":null,"outputs":[]},{"metadata":{"trusted":true},"cell_type":"code","source":"import tensorflow.keras.backend as K\n\ndef to_float32(image, label):\n    return tf.cast(image, tf.float32), label\n\n# TPUs need images in float format\ntrain_dataset = get_training_dataset().map(to_float32)\nvalid_dataset = get_validation_dataset().map(to_float32)\n\nSTEPS_PER_EPOCH = NUM_TRAINING_IMAGES // BATCH_SIZE\nVALID_STEPS = NUM_VALIDATION_IMAGES // BATCH_SIZE","execution_count":null,"outputs":[]},{"metadata":{},"cell_type":"markdown","source":"# Model fit"},{"metadata":{"trusted":true},"cell_type":"code","source":"history = model.fit(train_dataset, \n                    steps_per_epoch=STEPS_PER_EPOCH,\n                    epochs=20,\n                    validation_data=valid_dataset,\n                    validation_steps=VALID_STEPS,\n                    callbacks = [early_stopping, checkpoint, reduce_lr])","execution_count":null,"outputs":[]},{"metadata":{},"cell_type":"markdown","source":"# History"},{"metadata":{"trusted":true},"cell_type":"code","source":"history_frame = pd.DataFrame(history.history)\nhistory_frame.loc[:, ['loss', 'val_loss']].plot()\nhistory_frame.loc[:, ['sparse_categorical_accuracy', 'val_sparse_categorical_accuracy']].plot();","execution_count":null,"outputs":[]},{"metadata":{"trusted":true},"cell_type":"code","source":"model.save('./cass_efficientnetb7.h5')","execution_count":null,"outputs":[]},{"metadata":{"trusted":true},"cell_type":"code","source":"test_ds = get_test_dataset(ordered=True) # since we are splitting the dataset and iterating separately on images and ids, order matters.\ntest_ds = test_ds.map(to_float32)\n\nprint('Computing predictions...')\ntest_images_ds = test_ds.map(lambda image, idnum: image)\nprobabilities = model.predict(test_images_ds)\npredictions = np.argmax(probabilities, axis=-1)\nprint(predictions)","execution_count":null,"outputs":[]}],"metadata":{"kernelspec":{"language":"python","display_name":"Python 3","name":"python3"},"language_info":{"pygments_lexer":"ipython3","nbconvert_exporter":"python","version":"3.6.4","file_extension":".py","codemirror_mode":{"name":"ipython","version":3},"name":"python","mimetype":"text/x-python"}},"nbformat":4,"nbformat_minor":4}