GoogLeNet


import torch
model = torch.hub.load('pytorch/vision:v0.10.0', 'googlenet', pretrained=True)
model.eval()
所有預訓練模型都要求輸入影像以相同的方式進行歸一化,即由形狀為 (3 x H x W) 的 3 通道 RGB 影像組成的小批次資料,其中 H 和 W 預計至少為 224。影像必須載入到 [0, 1] 範圍內,然後使用 mean = [0.485, 0.456, 0.406] 和 std = [0.229, 0.224, 0.225] 進行歸一化。
這是一個示例執行。
# 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)
# 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())
模型描述
GoogLeNet 基於一個代號為“Inception”的深度卷積神經網路架構,該架構在 2014 年 ImageNet 大規模視覺識別挑戰賽 (ILSVRC 2014) 中,在分類和檢測方面創下了新的技術水平。使用預訓練模型在 ImageNet 資料集上的單裁剪錯誤率如下所示。
| 模型結構 | Top-1 錯誤率 | Top-5 錯誤率 |
|---|---|---|
| googlenet | 30.22 | 10.47 |
參考文獻