Merge pull request #198 from us:add-emnist-dataset

PiperOrigin-RevId: 238280883

tensorflow_datasets/image/__init__.py

@@ -30,6 +30,7 @@
 from tensorflow_datasets.image.image_folder import ImageLabelFolder
 from tensorflow_datasets.image.imagenet import Imagenet2012
 from tensorflow_datasets.image.lsun import Lsun
+from tensorflow_datasets.image.mnist import EMNIST
 from tensorflow_datasets.image.mnist import FashionMNIST
 from tensorflow_datasets.image.mnist import KMNIST
 from tensorflow_datasets.image.mnist import MNIST

tensorflow_datasets/image/mnist.py

@@ -13,16 +13,18 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""MNIST and Fashion MNIST."""
+"""MNIST, Fashion MNIST, KMNIST and EMNIST."""
 
 from __future__ import absolute_import
 from __future__ import division
 from __future__ import print_function
 
+import os
 import numpy as np
 import six.moves.urllib as urllib
 import tensorflow as tf
 
+from tensorflow_datasets.core import api_utils
 import tensorflow_datasets.public_api as tfds
 
 # MNIST constants
@@ -36,7 +38,6 @@
 _TRAIN_EXAMPLES = 60000
 _TEST_EXAMPLES = 10000
 
-
 _MNIST_CITATION = """\
 @article{lecun2010mnist,
   title={MNIST handwritten digit database},
@@ -47,7 +48,6 @@
 }
 """
 
-
 _FASHION_MNIST_CITATION = """\
 @article{DBLP:journals/corr/abs-1708-07747,
   author    = {Han Xiao and
@@ -67,25 +67,25 @@
 }
 """
 
-
 _K_MNIST_CITATION = """\
-@article{DBLP:journals/corr/abs-1812-01718,
-  author    = {Tarin Clanuwat and
-               Mikel Bober{-}Irizar and
-               Asanobu Kitamoto and
-               Alex Lamb and
-               Kazuaki Yamamoto and
-               David Ha},
-  title     = {Deep Learning for Classical Japanese Literature},
-  journal   = {CoRR},
-  volume    = {abs/1812.01718},
-  year      = {2018},
-  url       = {http://arxiv.org/abs/1812.01718},
-  archivePrefix = {arXiv},
-  eprint    = {1812.01718},
-  timestamp = {Tue, 01 Jan 2019 15:01:25 +0100},
-  biburl    = {https://dblp.org/rec/bib/journals/corr/abs-1812-01718},
-  bibsource = {dblp computer science bibliography, https://dblp.org}
+  @online{clanuwat2018deep,
+  author       = {Tarin Clanuwat and Mikel Bober-Irizar and Asanobu Kitamoto and Alex Lamb and Kazuaki Yamamoto and David Ha},
+  title        = {Deep Learning for Classical Japanese Literature},
+  date         = {2018-12-03},
+  year         = {2018},
+  eprintclass  = {cs.CV},
+  eprinttype   = {arXiv},
+  eprint       = {cs.CV/1812.01718},
+}
+"""
+
+_EMNIST_CITATION = """\
+@article{cohen_afshar_tapson_schaik_2017, 
+    title={EMNIST: Extending MNIST to handwritten letters}, 
+    DOI={10.1109/ijcnn.2017.7966217}, 
+    journal={2017 International Joint Conference on Neural Networks (IJCNN)}, 
+    author={Cohen, Gregory and Afshar, Saeed and Tapson, Jonathan and Schaik, Andre Van}, 
+    year={2017}
 }
 """
 
@@ -118,9 +118,8 @@ def _split_generators(self, dl_manager):
         "test_data": _MNIST_TEST_DATA_FILENAME,
         "test_labels": _MNIST_TEST_LABELS_FILENAME,
     }
-    mnist_files = dl_manager.download_and_extract({
-        k: urllib.parse.urljoin(self.URL, v) for k, v in filenames.items()
-    })
+    mnist_files = dl_manager.download_and_extract(
+        {k: urllib.parse.urljoin(self.URL, v) for k, v in filenames.items()})
 
     # MNIST provides TRAIN and TEST splits, not a VALIDATION split, so we only
     # write the TRAIN and TEST splits to disk.
@@ -181,11 +180,13 @@ def _info(self):
                      "grayscale image, associated with a label from 10 "
                      "classes."),
         features=tfds.features.FeaturesDict({
-            "image": tfds.features.Image(shape=_MNIST_IMAGE_SHAPE),
-            "label": tfds.features.ClassLabel(names=[
-                "T-shirt/top", "Trouser", "Pullover", "Dress", "Coat",
-                "Sandal", "Shirt", "Sneaker", "Bag", "Ankle boot"
-            ]),
+            "image":
+                tfds.features.Image(shape=_MNIST_IMAGE_SHAPE),
+            "label":
+                tfds.features.ClassLabel(names=[
+                    "T-shirt/top", "Trouser", "Pullover", "Dress", "Coat",
+                    "Sandal", "Shirt", "Sneaker", "Bag", "Ankle boot"
+                ]),
         }),
         supervised_keys=("image", "label"),
         urls=["https://github.com/zalandoresearch/fashion-mnist"],
@@ -208,17 +209,182 @@ def _info(self):
                      "character to represent each of the 10 rows of Hiragana "
                      "when creating Kuzushiji-MNIST."),
         features=tfds.features.FeaturesDict({
-            "image": tfds.features.Image(shape=_MNIST_IMAGE_SHAPE),
-            "label": tfds.features.ClassLabel(names=[
-                "o", "ki", "su", "tsu", "na", "ha", "ma", "ya", "re", "wo"
-            ]),
+            "image":
+                tfds.features.Image(shape=_MNIST_IMAGE_SHAPE),
+            "label":
+                tfds.features.ClassLabel(names=[
+                    "o", "ki", "su", "tsu", "na", "ha", "ma", "ya", "re", "wo"
+                ]),
         }),
         supervised_keys=("image", "label"),
         urls=["http://codh.rois.ac.jp/kmnist/index.html.en"],
         citation=_K_MNIST_CITATION,
     )
 
 
+class EMNISTConfig(tfds.core.BuilderConfig):
+  """BuilderConfig for EMNIST CONFIG."""
+
+  @api_utils.disallow_positional_args
+  def __init__(self, class_number, train_examples, test_examples, **kwargs):
+    """BuilderConfig for EMNIST class number.
+
+    Args:
+      class_number: There are six different splits provided in this dataset. And
+        have different class numbers.
+      train_examples: number of train examples
+      test_examples: number of test examples
+      **kwargs: keyword arguments forwarded to super.
+    """
+    super(EMNISTConfig, self).__init__(**kwargs)
+    self.class_number = class_number
+    self.train_examples = train_examples
+    self.test_examples = test_examples
+
+
+class EMNIST(MNIST):
+  """Emnist dataset."""
+
+  VERSION = tfds.core.Version("1.0.1")
+
+  BUILDER_CONFIGS = [
+      EMNISTConfig(
+          name="byclass",
+          class_number=62,
+          train_examples=697932,
+          test_examples=116323,
+          description="EMNIST ByClass:  814,255 characters. 62 unbalanced classes.",
+          version="1.0.1",
+      ),
+      EMNISTConfig(
+          name="bymerge",
+          class_number=47,
+          train_examples=697932,
+          test_examples=116323,
+          description="EMNIST ByMerge: 814,255 characters. 47 unbalanced classes.",
+          version="1.0.1",
+      ),
+      EMNISTConfig(
+          name="balanced",
+          class_number=47,
+          train_examples=112800,
+          test_examples=18800,
+          description="EMNIST Balanced:	131,600 characters. 47 balanced classes.",
+          version="1.0.1",
+      ),
+      EMNISTConfig(
+          name="letters",
+          class_number=37,
+          train_examples=88800,
+          test_examples=14800,
+          description="EMNIST Letters:	103,600 characters. 26 balanced classes.",
+          version="1.0.1",
+      ),
+      EMNISTConfig(
+          name="digits",
+          class_number=10,
+          train_examples=240000,
+          test_examples=40000,
+          description="EMNIST Digits:  280,000 characters. 10 balanced classes.",
+          version="1.0.1",
+      ),
+      EMNISTConfig(
+          name="mnist",
+          class_number=10,
+          train_examples=60000,
+          test_examples=10000,
+          description="EMNIST MNIST:  70,000 characters. 10 balanced classes.",
+          version="1.0.1",
+      ),
+      EMNISTConfig(
+          name="test",
+          class_number=62,
+          train_examples=10,
+          test_examples=2,
+          description="EMNIST test data config.",
+          version="1.0.1",
+      ),
+  ]
+
+  def _info(self):
+    return tfds.core.DatasetInfo(
+        builder=self,
+        description=(
+            "The EMNIST dataset is a set of handwritten character digits"
+            "derived from the NIST Special Database 19 and converted to"
+            "a 28x28 pixel image format and dataset structure that directly"
+            "matches the MNIST dataset."),
+        features=tfds.features.FeaturesDict({
+            "image":
+                tfds.features.Image(shape=_MNIST_IMAGE_SHAPE),
+            "label":
+                tfds.features.ClassLabel(
+                    num_classes=self.builder_config.class_number),
+        }),
+        supervised_keys=("image", "label"),
+        urls=["https://www.itl.nist.gov/iaui/vip/cs_links/EMNIST/gzip.zip"],
+        citation=_EMNIST_CITATION,
+    )
+
+  def _split_generators(self, dl_manager):
+
+    filenames = {
+        "train_data":
+            "emnist-{}-train-images-idx3-ubyte".format(
+                self.builder_config.name),
+        "train_labels":
+            "emnist-{}-train-labels-idx1-ubyte".format(
+                self.builder_config.name),
+        "test_data":
+            "emnist-{}-test-images-idx3-ubyte".format(self.builder_config.name),
+        "test_labels":
+            "emnist-{}-test-labels-idx1-ubyte".format(self.builder_config.name),
+    }
+
+    dir_name = dl_manager.manual_dir
+
+    if not tf.io.gfile.exists(os.path.join(dir_name, filenames["train_data"])):
+      # The current tfds.core.download_manager is unable to
+      # extract multiple and nested files.
+      # We'll add soon! (Issue 234)
+      msg = ("You must download and extract the dataset files manually and "
+             "place them in : ")
+      msg += dl_manager.manual_dir
+      msg += """File tree must be like this :\n
+               .
+              | -- emnist
+              |   |-- emnist-byclass-train-images-idx3-ubyte
+              |   |-- emnist-byclass-train-labels-idx3-ubyte
+              |   |-- emnist-byclass-test-images-idx3-ubyte
+              |   |-- emnist-byclass-test-labels-idx3-ubyte
+              |   |-- emnist-bymerge-train-images-idx3-ubyte
+              |   |-- emnist-bymerge-train-labels-idx3-ubyte
+              |   |-- emnist-bymerge-test-images-idx3-ubyte
+              |   |-- emnist-bymerge-test-labels-idx3-ubyte
+              |   |-- .......
+            """
+      raise Exception(msg.replace("               ", ""))
+
+    return [
+        tfds.core.SplitGenerator(
+            name=tfds.Split.TRAIN,
+            num_shards=10,
+            gen_kwargs=dict(
+                num_examples=self.builder_config.train_examples,
+                data_path=os.path.join(dir_name, filenames["train_data"]),
+                label_path=os.path.join(dir_name, filenames["train_labels"]),
+            )),
+        tfds.core.SplitGenerator(
+            name=tfds.Split.TEST,
+            num_shards=1,
+            gen_kwargs=dict(
+                num_examples=self.builder_config.test_examples,
+                data_path=os.path.join(dir_name, filenames["test_data"]),
+                label_path=os.path.join(dir_name, filenames["test_labels"]),
+            ))
+    ]
+
+
 def _extract_mnist_images(image_filepath, num_images):
   with tf.io.gfile.GFile(image_filepath, "rb") as f:
     f.read(16)  # header

tensorflow_datasets/image/mnist_test.py

@@ -51,5 +51,10 @@ class KMNISTTest(MNISTTest):
   DATASET_CLASS = mnist.KMNIST
 
 
+class EMNISTTest(MNISTTest):
+  DATASET_CLASS = mnist.EMNIST
+  BUILDER_CONFIG_NAMES_TO_TEST = ["test"]
+
+
 if __name__ == "__main__":
   testing.test_main()

tensorflow_datasets/testing/mnist.py

@@ -71,7 +71,7 @@ def write_label_file(filename, num_labels):
 
 
 def main(_):
-  for mnist in ["mnist", "fashion_mnist", "kmnist"]:
+  for mnist in ["mnist", "fashion_mnist", "kmnist", "emnist"]:
     output_dir = mnist_dir(mnist)
     test_utils.remake_dir(output_dir)
     write_image_file(os.path.join(output_dir, _TRAIN_DATA_FILENAME), 10)

tensorflow_datasets/testing/test_data/fake_examples/emnist/emnist-test-test-labels-idx1-ubyte

@@ -0,0 +1 @@
+11111111

tensorflow_datasets/testing/test_data/fake_examples/emnist/emnist-test-train-labels-idx1-ubyte

@@ -0,0 +1 @@
+11111111