Merge pull request #1187 from solopku/patch-3

examples/cnn_ms/data/cifar10.py

@@ -0,0 +1,89 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+try:
+    import pickle
+except ImportError:
+    import cPickle as pickle
+
+import numpy as np
+import os
+import sys
+
+
+def load_dataset(filepath):
+    with open(filepath, 'rb') as fd:
+        try:
+            cifar10 = pickle.load(fd, encoding='latin1')
+        except TypeError:
+            cifar10 = pickle.load(fd)
+    image = cifar10['data'].astype(dtype=np.uint8)
+    image = image.reshape((-1, 3, 32, 32))
+    label = np.asarray(cifar10['labels'], dtype=np.uint8)
+    label = label.reshape(label.size, 1)
+    return image, label
+
+
+def load_train_data(dir_path='/tmp/cifar-10-batches-py', num_batches=5):  # need to save to specific local directories
+    labels = []
+    batchsize = 10000
+    images = np.empty((num_batches * batchsize, 3, 32, 32), dtype=np.uint8)
+    for did in range(1, num_batches + 1):
+        fname_train_data = dir_path + "/data_batch_{}".format(did)
+        image, label = load_dataset(check_dataset_exist(fname_train_data))
+        images[(did - 1) * batchsize:did * batchsize] = image
+        labels.extend(label)
+    images = np.array(images, dtype=np.float32)
+    labels = np.array(labels, dtype=np.int32)
+    return images, labels
+
+
+def load_test_data(dir_path='/tmp/cifar-10-batches-py'):  # need to save to specific local directories
+    images, labels = load_dataset(check_dataset_exist(dir_path + "/test_batch"))
+    return np.array(images, dtype=np.float32), np.array(labels, dtype=np.int32)
+
+
+def check_dataset_exist(dirpath):
+    if not os.path.exists(dirpath):
+        print(
+            'Please download the cifar10 dataset using python data/download_cifar10.py'
+        )
+        sys.exit(0)
+    return dirpath
+
+
+def normalize(train_x, val_x):
+    mean = [0.4914, 0.4822, 0.4465]
+    std = [0.2023, 0.1994, 0.2010]
+    train_x /= 255
+    val_x /= 255
+    for ch in range(0, 2):
+        train_x[:, ch, :, :] -= mean[ch]
+        train_x[:, ch, :, :] /= std[ch]
+        val_x[:, ch, :, :] -= mean[ch]
+        val_x[:, ch, :, :] /= std[ch]
+    return train_x, val_x
+
+def load():
+    train_x, train_y = load_train_data()
+    val_x, val_y = load_test_data()
+    train_x, val_x = normalize(train_x, val_x)
+    train_y = train_y.flatten()
+    val_y = val_y.flatten()
+    return train_x, train_y, val_x, val_y