Remove PyTorch APIs (#2280)

* add transforms.py and rename torchvision_reader.py to reader.py

* add datasets.py

* remove pytorch apis

* fix some small bugs

* remove torch and torchvision from requirements.txt

* modify core.CUDAPlace to fluid.CUDAPlace

PaddleCV/image_classification/fast_imagenet/datasets.py

+from PIL import Image
+
+import os
+import os.path
+import sys
+
+IMG_EXTENSIONS = ('.jpg', '.jpeg', '.png', '.bmp', '.tif', '.tiff')
+
+
+def has_file_allowed_extension(filename, extensions):
+    """Checks if a file is an allowed extension.
+
+    Args:
+        filename (string): path to a file
+        extensions (tuple of strings): extensions to consider (lowercase)
+
+    Returns:
+        bool: True if the filename ends with one of given extensions
+    """
+    return filename.lower().endswith(extensions)
+
+
+def is_image_file(filename):
+    """Checks if a file is an allowed image extension.
+
+    Args:
+        filename (string): path to a file
+
+    Returns:
+        bool: True if the filename ends with a known image extension
+    """
+    return has_file_allowed_extension(filename, IMG_EXTENSIONS)
+
+
+def make_dataset(dir, class_to_idx, extensions):
+    images = []
+    dir = os.path.expanduser(dir)
+    for target in sorted(class_to_idx.keys()):
+        d = os.path.join(dir, target)
+        if not os.path.isdir(d):
+            continue
+
+        for root, _, fnames in sorted(os.walk(d)):
+            for fname in sorted(fnames):
+                if has_file_allowed_extension(fname, extensions):
+                    path = os.path.join(root, fname)
+                    item = (path, class_to_idx[target])
+                    images.append(item)
+
+    return images
+
+
+class DatasetFolder(object):
+    """A generic data loader where the samples are arranged in this way: ::
+
+        root/class_x/xxx.ext
+        root/class_x/xxy.ext
+        root/class_x/xxz.ext
+
+        root/class_y/123.ext
+        root/class_y/nsdf3.ext
+        root/class_y/asd932_.ext
+
+    Args:
+        root (string): Root directory path.
+        loader (callable): A function to load a sample given its path.
+        extensions (tuple[string]): A list of allowed extensions.
+        transform (callable, optional): A function/transform that takes in
+            a sample and returns a transformed version.
+            E.g, ``transforms.RandomCrop`` for images.
+        target_transform (callable, optional): A function/transform that takes
+            in the target and transforms it.
+
+     Attributes:
+        classes (list): List of the class names.
+        class_to_idx (dict): Dict with items (class_name, class_index).
+        samples (list): List of (sample path, class_index) tuples
+        targets (list): The class_index value for each image in the dataset
+    """
+
+    def __init__(self,
+                 root,
+                 loader,
+                 extensions,
+                 transform=None,
+                 target_transform=None):
+        self.root = root
+        self.transform = transform
+        self.target_transform = target_transform
+        classes, class_to_idx = self._find_classes(self.root)
+        samples = make_dataset(self.root, class_to_idx, extensions)
+        if len(samples) == 0:
+            raise (RuntimeError(
+                "Found 0 files in subfolders of: " + self.root + "\n"
+                "Supported extensions are: " + ",".join(extensions)))
+
+        self.loader = loader
+        self.extensions = extensions
+
+        self.classes = classes
+        self.class_to_idx = class_to_idx
+        self.samples = samples
+        self.targets = [s[1] for s in samples]
+
+    def _find_classes(self, dir):
+        """
+        Finds the class folders in a dataset.
+
+        Args:
+            dir (string): Root directory path.
+
+        Returns:
+            tuple: (classes, class_to_idx) where classes are relative to (dir), and class_to_idx is a dictionary.
+
+        Ensures:
+            No class is a subdirectory of another.
+        """
+        if sys.version_info >= (3, 5):
+            # Faster and available in Python 3.5 and above
+            classes = [d.name for d in os.scandir(dir) if d.is_dir()]
+        else:
+            classes = [
+                d for d in os.listdir(dir)
+                if os.path.isdir(os.path.join(dir, d))
+            ]
+        classes.sort()
+        class_to_idx = {classes[i]: i for i in range(len(classes))}
+        return classes, class_to_idx
+
+    def __getitem__(self, index):
+        """
+        Args:
+            index (int): Index
+
+        Returns:
+            tuple: (sample, target) where target is class_index of the target class.
+        """
+        path, target = self.samples[index]
+        sample = self.loader(path)
+        if self.transform is not None:
+            sample = self.transform(sample)
+        if self.target_transform is not None:
+            target = self.target_transform(target)
+
+        return sample, target
+
+    def __len__(self):
+        return len(self.samples)
+
+
+def pil_loader(path):
+    # open path as file to avoid ResourceWarning (https://github.com/python-pillow/Pillow/issues/835)
+    with open(path, 'rb') as f:
+        img = Image.open(f)
+        return img.convert('RGB')
+
+
+def default_loader(path):
+    return pil_loader(path)
+
+
+class ImageFolder(DatasetFolder):
+    """A generic data loader where the images are arranged in this way: ::
+
+        root/dog/xxx.png
+        root/dog/xxy.png
+        root/dog/xxz.png
+
+        root/cat/123.png
+        root/cat/nsdf3.png
+        root/cat/asd932_.png
+
+    Args:
+        root (string): Root directory path.
+        transform (callable, optional): A function/transform that  takes in an PIL image
+            and returns a transformed version. E.g, ``transforms.RandomCrop``
+        target_transform (callable, optional): A function/transform that takes in the
+            target and transforms it.
+        loader (callable, optional): A function to load an image given its path.
+
+     Attributes:
+        classes (list): List of the class names.
+        class_to_idx (dict): Dict with items (class_name, class_index).
+        imgs (list): List of (image path, class_index) tuples
+    """
+
+    def __init__(self,
+                 root,
+                 transform=None,
+                 target_transform=None,
+                 loader=default_loader):
+        super(ImageFolder, self).__init__(
+            root,
+            loader,
+            IMG_EXTENSIONS,
+            transform=transform,
+            target_transform=target_transform)
+        self.imgs = self.samples

PaddleCV/image_classification/fast_imagenet/torchvision_reader.py → PaddleCV/image_classification/fast_imagenet/reader.py

@@ -4,31 +4,27 @@ import os
 import numpy as np
 import math
 import random
-import torch
-import torch.utils.data
-from torch.utils.data.distributed import DistributedSampler
-import torchvision.transforms as transforms
-import torchvision.datasets as datasets
-
-from torch.utils.data.sampler import Sampler
-import torchvision
+
 import pickle
 from tqdm import tqdm
 import time
 import multiprocessing
 
+import transforms
+import datasets
+
 FINISH_EVENT = "FINISH_EVENT"
 
 
 class PaddleDataLoader(object):
     def __init__(self,
-                 torch_dataset,
+                 dataset,
                  indices=None,
                  concurrent=24,
                  queue_size=3072,
                  shuffle=True,
                  shuffle_seed=0):
-        self.torch_dataset = torch_dataset
+        self.dataset = dataset
         self.indices = indices
         self.concurrent = concurrent
         self.shuffle = shuffle
@@ -39,7 +35,7 @@ class PaddleDataLoader(object):
         cnt = 0
         for idx in worker_indices:
             cnt += 1
-            img, label = self.torch_dataset[idx]
+            img, label = self.dataset[idx]
             img = np.array(img).astype('uint8').transpose((2, 0, 1))
             queue.put((img, label))
         print("worker: [%d] read [%d] samples. " % (worker_id, cnt))
@@ -49,7 +45,7 @@ class PaddleDataLoader(object):
         def _reader_creator():
             worker_processes = []
             index_queues = []
-            total_img = len(self.torch_dataset)
+            total_img = len(self.dataset)
             print("total image: ", total_img)
             if self.shuffle:
                 self.indices = [i for i in xrange(total_img)]
@@ -146,7 +142,7 @@ class CropArTfm(object):
         else:
             h = int(self.target_size * target_ar)
             size = (self.target_size, h // 8 * 8)
-        return torchvision.transforms.functional.center_crop(img, size)
+        return transforms.center_crop(img, size)
 
 
 def sort_ar(valdir):

PaddleCV/image_classification/fast_imagenet/requirements.txt

-torch==0.4.1
-torchvision
 tqdm

PaddleCV/image_classification/fast_imagenet/train.py

@@ -19,8 +19,8 @@ import os
 import traceback
 
 import numpy as np
-import torchvision_reader
-import torch
+import math
+import reader
 import paddle
 import paddle.fluid as fluid
 import paddle.fluid.profiler as profiler
@@ -235,9 +235,19 @@ def refresh_program(args,
             if var.name.startswith('conv2d_')
         ]
         for var in conv2d_w_vars:
-            torch_w = torch.empty(var.shape)
-            kaiming_np = torch.nn.init.kaiming_normal_(
-                torch_w, mode='fan_out', nonlinearity='relu').numpy()
+            #torch_w = torch.empty(var.shape)
+            #kaiming_np = torch.nn.init.kaiming_normal_(torch_w, mode='fan_out', nonlinearity='relu').numpy()
+            shape = var.shape
+            if not shape or len(shape) == 0:
+                fan_out = 1
+            elif len(shape) == 1:
+                fan_out = shape[0]
+            elif len(shape) == 2:
+                fan_out = shape[1]
+            else:
+                fan_out = shape[0] * np.prod(shape[2:])
+            std = math.sqrt(2.0 / fan_out)
+            kaiming_np = np.random.normal(0, std, var.shape)
             tensor = fluid.global_scope().find_var(var.name).get_tensor()
             if args.fp16:
                 tensor.set(np.array(
@@ -283,7 +293,7 @@ def refresh_program(args,
 
 def prepare_reader(epoch_id, train_py_reader, train_bs, val_bs, trn_dir,
                    img_dim, min_scale, rect_val):
-    train_reader = torchvision_reader.train(
+    train_reader = reader.train(
         traindir="/data/imagenet/%strain" % trn_dir,
         sz=img_dim,
         min_scale=min_scale,
@@ -292,7 +302,7 @@ def prepare_reader(epoch_id, train_py_reader, train_bs, val_bs, trn_dir,
         paddle.batch(
             train_reader, batch_size=train_bs))
 
-    test_reader = torchvision_reader.test(
+    test_reader = reader.test(
         valdir="/data/imagenet/%svalidation" % trn_dir,
         bs=val_bs * DEVICE_NUM,
         sz=img_dim,

PaddleCV/image_classification/fast_imagenet/transforms.py

+from __future__ import division
+import math
+import random
+from PIL import Image
+import numpy as np
+import warnings
+
+__all__ = [
+    "Compose", "Resize", "Scale", "RandomHorizontalFlip", "RandomResizedCrop",
+    "CenterCrop"
+]
+
+
+def _is_pil_image(img):
+    return isinstance(img, Image.Image)
+
+
+def crop(img, i, j, h, w):
+    if not _is_pil_image(img):
+        raise TypeError('img should be a PIL Image, but be {}'.format(
+            type(img)))
+    return img.crop((j, i, j + w, i + h))
+
+
+def resize(img, size, interpolation=Image.BILINEAR):
+    if not _is_pil_image(img):
+        raise TypeError('img should be a PIL Image, but be {}'.format(
+            type(img)))
+    if not (isinstance(size, int) or
+            (isinstance(size, tuple) and len(size) == 2)):
+        raise TypeError('Wrong size arg: {}'.format(size))
+    if isinstance(size, int):
+        w, h = img.size
+        if (w <= h and w == size) or (h <= w and h == size):
+            return img
+        if w < h:
+            ow = size
+            oh = int(size * h / w)
+            return img.resize((ow, oh), interpolation)
+        else:
+            oh = size
+            ow = int(size * w / h)
+            return img.resize((ow, oh), interpolation)
+    else:
+        return img.resize(size[::-1], interpolation)
+
+
+def center_crop(img, output_size):
+    if isinstance(output_size, int):
+        output_size = (output_size, output_size)
+    w, h = img.size
+    th, tw = output_size
+    i = int(round((h - th) / 2.))
+    j = int(round((w - tw) / 2.))
+    return crop(img, i, j, th, tw)
+
+
+class Compose(object):
+    """Make some transforms in a chain.
+
+    Args:
+        transforms (list): list of transforms to be in a chain.
+    """
+
+    def __init__(self, transforms):
+        self._transforms = transforms
+
+    def __call__(self, img):
+        for t in self._transforms:
+            img = t(img)
+        return img
+
+
+class Resize(object):
+    """Resize the input PIL Image.
+
+    Args:
+        size (tuple | int): Output size. If the size is a tuple,
+            resize image to that size (h, w). If the size is an int,
+            smaller edge of the image will be resized to this size.
+        interpolation (int): Interpolation method.
+    """
+
+    def __init__(self, size, interpolation=Image.BILINEAR):
+        assert isinstance(size, int) or (isinstance(size, tuple) and
+                                         len(size) == 2)
+        self._size = size
+        self._interpolation = interpolation
+
+    def __call__(self, img):
+        """
+        Args:
+            img (PIL Image): Image to be resized.
+
+        Returns:
+            PIL Image: Resized image.
+        """
+        return resize(img, self._size, self._interpolation)
+
+
+class Scale(Resize):
+    """
+    Note: This transform is deprecated in favor of Resize.
+    """
+
+    def __init__(self, *args, **kwargs):
+        warnings.warn(
+            "The use of the transforms.Scale transform is deprecated, " +
+            "please use transforms.Resize instead.")
+        super(Scale, self).__init__(*args, **kwargs)
+
+
+class RandomHorizontalFlip(object):
+    """Horizontally flip the given PIL Image randomly with a given probability.
+
+    Args:
+        p (float): probability of the image being flipped. Default value is 0.5
+    """
+
+    def __init__(self, p=0.5):
+        self.p = p
+
+    def __call__(self, img):
+        """
+        Args:
+            img (PIL Image): Image to be flipped.
+
+        Returns:
+            PIL Image: Randomly flipped image.
+        """
+        if random.random() < self.p:
+            if not _is_pil_image(img):
+                raise TypeError('img should be a PIL image, but be {}'.format(
+                    type(img)))
+            return img.transpose(Image.FLIP_LEFT_RIGHT)
+        return img
+
+
+class RandomResizedCrop(object):
+    """Crop the input PIL Image to random size and aspect ratio, and then
+       resize the PIL Image to target size.
+
+    Args:
+        size: target size
+        scale: range of ratio of the origin size to be cropped
+        ratio: range of aspect ratio of the origin aspect ratio to be cropped
+        interpolation: interpolation method
+    """
+
+    def __init__(self,
+                 size,
+                 scale=(0.08, 1.0),
+                 ratio=(3. / 4., 4. / 3.),
+                 interpolation=Image.BILINEAR):
+        if isinstance(size, tuple):
+            self._size = size
+        else:
+            self._size = (size, size)
+        if (scale[0] > scale[1]) or (ratio[0] > ratio[1]):
+            raise ErrorValue("range should be of kind of (min, max)")
+
+        self._interpolation = interpolation
+        self._scale = scale
+        self._ratio = ratio
+
+    @staticmethod
+    def get_params(img, scale, ratio):
+        """Get parameters for ``crop`` for a random sized crop.
+
+        Args:
+            img (PIL Image): Image to be cropped.
+            scale (tuple): range of size of the origin size cropped
+            ratio (tuple): range of aspect ratio of the origin aspect ratio cropped
+
+        Returns:
+            tuple: params (i, j, h, w) to be passed to ``crop`` for a random
+                sized crop.
+        """
+        area = img.size[0] * img.size[1]
+
+        for attempt in range(10):
+            target_area = random.uniform(*scale) * area
+            log_ratio = (math.log(ratio[0]), math.log(ratio[1]))
+            aspect_ratio = math.exp(random.uniform(*log_ratio))
+
+            w = int(round(math.sqrt(target_area * aspect_ratio)))
+            h = int(round(math.sqrt(target_area / aspect_ratio)))
+
+            if w <= img.size[0] and h <= img.size[1]:
+                i = random.randint(0, img.size[1] - h)
+                j = random.randint(0, img.size[0] - w)
+                return i, j, h, w
+
+        # Fallback to central crop
+        in_ratio = img.size[0] / img.size[1]
+        if (in_ratio < min(ratio)):
+            w = img.size[0]
+            h = w / min(ratio)
+        elif (in_ratio > max(ratio)):
+            h = img.size[1]
+            w = h * max(ratio)
+        else:  # whole image
+            w = img.size[0]
+            h = img.size[1]
+        i = (img.size[1] - h) // 2
+        j = (img.size[0] - w) // 2
+        return i, j, h, w
+
+    def __call__(self, img):
+        """
+        Args:
+            img (PIL Image): Image to be cropped and resized.
+
+        Returns:
+            PIL Image: Randomly cropped and resized image.
+        """
+        i, j, h, w = self.get_params(img, self._scale, self._ratio)
+        assert _is_pil_image(img), 'image should be a PIL Image'
+        img = crop(img, i, j, h, w)
+        img = resize(img, self._size, self._interpolation)
+        return img
+
+
+class CenterCrop(object):
+    """Crops the given PIL Image at the center.
+
+    Args:
+        size (tuple|int): Output size. If size is an int instead of a tuple
+            like (h, w), a square crop (size, size) is made.
+    """
+
+    def __init__(self, size):
+        if isinstance(size, int):
+            self.size = (size, size)
+        else:
+            self.size = size
+
+    def __call__(self, img):
+        return center_crop(img, self.size)