Add EfficientNet Architecture in TorchVision (#4293)

* Adding code skeleton

* Adding MBConvConfig.

* Extend SqueezeExcitation to support custom min_value and activation.

* Implement MBConv.

* Replace stochastic_depth with operator.

* Adding the rest of the EfficientNet implementation

* Update torchvision/models/efficientnet.py

* Replacing 1st activation of SE with SiLU.

* Adding efficientnet_b3.

* Replace mobilenetv3 assets with custom.

* Switch to standard sigmoid and reconfiguring BN.

* Reconfiguration of efficientnet.

* Add repr

* Add weights.

* Update weights.

* Adding B5-B7 weights.

* Update docs and hubconf.

* Fix doc link.

* Fix typo on comment.

Author: datumbox

docs/source/models.rst

@@ -27,6 +27,7 @@ architectures for image classification:
 -  `ResNeXt`_
 -  `Wide ResNet`_
 -  `MNASNet`_
+-  `EfficientNet`_
 
 You can construct a model with random weights by calling its constructor:
 
@@ -47,6 +48,14 @@ You can construct a model with random weights by calling its constructor:
     resnext50_32x4d = models.resnext50_32x4d()
     wide_resnet50_2 = models.wide_resnet50_2()
     mnasnet = models.mnasnet1_0()
+    efficientnet_b0 = models.efficientnet_b0()
+    efficientnet_b1 = models.efficientnet_b1()
+    efficientnet_b2 = models.efficientnet_b2()
+    efficientnet_b3 = models.efficientnet_b3()
+    efficientnet_b4 = models.efficientnet_b4()
+    efficientnet_b5 = models.efficientnet_b5()
+    efficientnet_b6 = models.efficientnet_b6()
+    efficientnet_b7 = models.efficientnet_b7()
 
 We provide pre-trained models, using the PyTorch :mod:`torch.utils.model_zoo`.
 These can be constructed by passing ``pretrained=True``:
@@ -68,6 +77,14 @@ These can be constructed by passing ``pretrained=True``:
     resnext50_32x4d = models.resnext50_32x4d(pretrained=True)
     wide_resnet50_2 = models.wide_resnet50_2(pretrained=True)
     mnasnet = models.mnasnet1_0(pretrained=True)
+    efficientnet_b0 = models.efficientnet_b0(pretrained=True)
+    efficientnet_b1 = models.efficientnet_b1(pretrained=True)
+    efficientnet_b2 = models.efficientnet_b2(pretrained=True)
+    efficientnet_b3 = models.efficientnet_b3(pretrained=True)
+    efficientnet_b4 = models.efficientnet_b4(pretrained=True)
+    efficientnet_b5 = models.efficientnet_b5(pretrained=True)
+    efficientnet_b6 = models.efficientnet_b6(pretrained=True)
+    efficientnet_b7 = models.efficientnet_b7(pretrained=True)
 
 Instancing a pre-trained model will download its weights to a cache directory.
 This directory can be set using the `TORCH_MODEL_ZOO` environment variable. See
@@ -113,7 +130,10 @@ Unfortunately, the concrete `subset` that was used is lost. For more
 information see `this discussion <https://github.com/pytorch/vision/issues/1439>`_
 or `these experiments <https://github.com/pytorch/vision/pull/1965>`_.
 
-ImageNet 1-crop error rates (224x224)
+The sizes of the EfficientNet models depend on the variant. For the exact input sizes
+`check here <https://github.com/pytorch/vision/blob/d2bfd639e46e1c5dc3c177f889dc7750c8d137c7/references/classification/train.py#L92-L93>`_
+
+ImageNet 1-crop error rates
 
 ================================  =============   =============
 Model                             Acc@1           Acc@5
@@ -151,6 +171,14 @@ Wide ResNet-50-2                  78.468          94.086
 Wide ResNet-101-2                 78.848          94.284
 MNASNet 1.0                       73.456          91.510
 MNASNet 0.5                       67.734          87.490
+EfficientNet-B0                   77.692          93.532
+EfficientNet-B1                   78.642          94.186
+EfficientNet-B2                   80.608          95.310
+EfficientNet-B3                   82.008          96.054
+EfficientNet-B4                   83.384          96.594
+EfficientNet-B5                   83.444          96.628
+EfficientNet-B6                   84.008          96.916
+EfficientNet-B7                   84.122          96.908
 ================================  =============   =============
 
 
@@ -166,6 +194,7 @@ MNASNet 0.5                       67.734          87.490
 .. _MobileNetV3: https://arxiv.org/abs/1905.02244
 .. _ResNeXt: https://arxiv.org/abs/1611.05431
 .. _MNASNet: https://arxiv.org/abs/1807.11626
+.. _EfficientNet: https://arxiv.org/abs/1905.11946
 
 .. currentmodule:: torchvision.models
 
@@ -267,6 +296,18 @@ MNASNet
 .. autofunction:: mnasnet1_0
 .. autofunction:: mnasnet1_3
 
+EfficientNet
+------------
+
+.. autofunction:: efficientnet_b0
+.. autofunction:: efficientnet_b1
+.. autofunction:: efficientnet_b2
+.. autofunction:: efficientnet_b3
+.. autofunction:: efficientnet_b4
+.. autofunction:: efficientnet_b5
+.. autofunction:: efficientnet_b6
+.. autofunction:: efficientnet_b7
+
 Quantized Models
 ----------------
 

hubconf.py

@@ -15,6 +15,8 @@
 from torchvision.models.mobilenetv3 import mobilenet_v3_large, mobilenet_v3_small
 from torchvision.models.mnasnet import mnasnet0_5, mnasnet0_75, mnasnet1_0, \
     mnasnet1_3
+from torchvision.models.efficientnet import efficientnet_b0, efficientnet_b1, efficientnet_b2, \
+    efficientnet_b3, efficientnet_b4, efficientnet_b5, efficientnet_b6, efficientnet_b7
 
 # segmentation
 from torchvision.models.segmentation import fcn_resnet50, fcn_resnet101, \

references/classification/README.md

@@ -68,6 +68,12 @@ Then we averaged the parameters of the last 3 checkpoints that improved the Acc@
 and [#3354](https://github.com/pytorch/vision/pull/3354) for details.
 
 
+### EfficientNet
+
+The weights of the B0-B4 variants are ported from Ross Wightman's [timm repo](https://github.com/rwightman/pytorch-image-models/blob/01cb46a9a50e3ba4be167965b5764e9702f09b30/timm/models/efficientnet.py#L95-L108).
+
+The weights of the B5-B7 variants are ported from Luke Melas' [EfficientNet-PyTorch repo](https://github.com/lukemelas/EfficientNet-PyTorch/blob/1039e009545d9329ea026c9f7541341439712b96/efficientnet_pytorch/utils.py#L562-L564).
+
 ## Mixed precision training
 Automatic Mixed Precision (AMP) training on GPU for Pytorch can be enabled with the [NVIDIA Apex extension](https://github.com/NVIDIA/apex).
 

references/classification/presets.py

@@ -1,4 +1,5 @@
 from torchvision.transforms import autoaugment, transforms
+from torchvision.transforms.functional import InterpolationMode
 
 
 class ClassificationPresetTrain:
@@ -24,10 +25,11 @@ def __call__(self, img):
 
 
 class ClassificationPresetEval:
-    def __init__(self, crop_size, resize_size=256, mean=(0.485, 0.456, 0.406), std=(0.229, 0.224, 0.225)):
+    def __init__(self, crop_size, resize_size=256, mean=(0.485, 0.456, 0.406), std=(0.229, 0.224, 0.225),
+                 interpolation=InterpolationMode.BILINEAR):
 
         self.transforms = transforms.Compose([
-            transforms.Resize(resize_size),
+            transforms.Resize(resize_size, interpolation=interpolation),
             transforms.CenterCrop(crop_size),
             transforms.ToTensor(),
             transforms.Normalize(mean=mean, std=std),

references/classification/train.py

@@ -6,6 +6,7 @@
 import torch.utils.data
 from torch import nn
 import torchvision
+from torchvision.transforms.functional import InterpolationMode
 
 import presets
 import utils
@@ -82,7 +83,18 @@ def _get_cache_path(filepath):
 def load_data(traindir, valdir, args):
     # Data loading code
     print("Loading data")
-    resize_size, crop_size = (342, 299) if args.model == 'inception_v3' else (256, 224)
+    resize_size, crop_size = 256, 224
+    interpolation = InterpolationMode.BILINEAR
+    if args.model == 'inception_v3':
+        resize_size, crop_size = 342, 299
+    elif args.model.startswith('efficientnet_'):
+        sizes = {
+            'b0': (256, 224), 'b1': (256, 240), 'b2': (288, 288), 'b3': (320, 300),
+            'b4': (384, 380), 'b5': (456, 456), 'b6': (528, 528), 'b7': (600, 600),
+        }
+        e_type = args.model.replace('efficientnet_', '')
+        resize_size, crop_size = sizes[e_type]
+        interpolation = InterpolationMode.BICUBIC
 
     print("Loading training data")
     st = time.time()
@@ -113,7 +125,8 @@ def load_data(traindir, valdir, args):
     else:
         dataset_test = torchvision.datasets.ImageFolder(
             valdir,
-            presets.ClassificationPresetEval(crop_size=crop_size, resize_size=resize_size))
+            presets.ClassificationPresetEval(crop_size=crop_size, resize_size=resize_size,
+                                             interpolation=interpolation))
         if args.cache_dataset:
             print("Saving dataset_test to {}".format(cache_path))
             utils.mkdir(os.path.dirname(cache_path))