--- layout: hub_detail background-class: hub-background body-class: hub title: vgg-nets summary: Award winning ConvNets from 2014 ImageNet ILSVRC challenge category: researchers image: vgg.png author: Pytorch Team tags: [vision, scriptable] github-link: https://github.com/pytorch/vision/blob/main/torchvision/models/vgg.py github-id: pytorch/vision featured_image_1: vgg.png featured_image_2: no-image accelerator: cuda-optional order: 10 demo-model-link: https://huggingface.co/spaces/pytorch/vgg-nets --- ```python import torch model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg11', pretrained=True) # or any of these variants # model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg11_bn', pretrained=True) # model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg13', pretrained=True) # model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg13_bn', pretrained=True) # model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg16', pretrained=True) # model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg16_bn', pretrained=True) # model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg19', pretrained=True) # model = torch.hub.load('pytorch/vision:v0.10.0', 'vgg19_bn', pretrained=True) model.eval() ``` All pre-trained models expect input images normalized in the same way, i.e. mini-batches of 3-channel RGB images of shape `(3 x H x W)`, where `H` and `W` are expected to be at least `224`. The images have to be loaded in to a range of `[0, 1]` and then normalized using `mean = [0.485, 0.456, 0.406]` and `std = [0.229, 0.224, 0.225]`. Here's a sample execution. ```python # Download an example image from the pytorch website import urllib url, filename = ("https://github.com/pytorch/hub/raw/master/images/dog.jpg", "dog.jpg") try: urllib.URLopener().retrieve(url, filename) except: urllib.request.urlretrieve(url, filename) ``` ```python # sample execution (requires torchvision) from PIL import Image from torchvision import transforms input_image = Image.open(filename) preprocess = transforms.Compose([ transforms.Resize(256), transforms.CenterCrop(224), transforms.ToTensor(), transforms.Normalize(mean=[0.485, 0.456, 0.406], std=[0.229, 0.224, 0.225]), ]) input_tensor = preprocess(input_image) input_batch = input_tensor.unsqueeze(0) # create a mini-batch as expected by the model # move the input and model to GPU for speed if available if torch.cuda.is_available(): input_batch = input_batch.to('cuda') model.to('cuda') with torch.no_grad(): output = model(input_batch) # Tensor of shape 1000, with confidence scores over ImageNet's 1000 classes print(output[0]) # The output has unnormalized scores. To get probabilities, you can run a softmax on it. probabilities = torch.nn.functional.softmax(output[0], dim=0) print(probabilities) ``` ``` # Download ImageNet labels !wget https://raw.githubusercontent.com/pytorch/hub/master/imagenet_classes.txt ``` ``` # Read the categories with open("imagenet_classes.txt", "r") as f: categories = [s.strip() for s in f.readlines()] # Show top categories per image top5_prob, top5_catid = torch.topk(probabilities, 5) for i in range(top5_prob.size(0)): print(categories[top5_catid[i]], top5_prob[i].item()) ``` ### Model Description Here we have implementations for the models proposed in [Very Deep Convolutional Networks for Large-Scale Image Recognition](https://arxiv.org/abs/1409.1556), for each configurations and their with batchnorm version. For example, configuration `A` presented in the paper is `vgg11`, configuration `B` is `vgg13`, configuration `D` is `vgg16` and configuration `E` is `vgg19`. Their batchnorm version are suffixed with `_bn`. Their Top-1 error rates on ImageNet dataset with pretrained models are listed below. | Model structure | Top-1 error | Top-5 error | | --------------- | ----------- | ----------- | | vgg11 | 30.98 | 11.37 | | vgg11_bn | 26.70 | 8.58 | | vgg13 | 30.07 | 10.75 | | vgg13_bn | 28.45 | 9.63 | | vgg16 | 28.41 | 9.62 | | vgg16_bn | 26.63 | 8.50 | | vgg19 | 27.62 | 9.12 | | vgg19_bn | 25.76 | 8.15 | ### References - [Very Deep Convolutional Networks for Large-Scale Image Recognition](https://arxiv.org/abs/1409.1556).