DenseNet

DenseNet 是一種卷積神經網路，它透過密集塊在層之間使用密集連線，將所有（具有匹配特徵圖大小的）層直接相互連線。為了保持前饋性質，每個層從所有前置層獲得額外的輸入，並將其自身的特徵圖傳遞給所有後續層。

Ross Wightman 集合中的 DenseNet Blur 變體採用了模糊池化。

如何在影像上使用此模型？

載入預訓練模型

>>> import timm
>>> model = timm.create_model('densenet121', pretrained=True)
>>> model.eval()

載入並預處理影像

>>> import urllib
>>> from PIL import Image
>>> from timm.data import resolve_data_config
>>> from timm.data.transforms_factory import create_transform

>>> config = resolve_data_config({}, model=model)
>>> transform = create_transform(**config)

>>> url, filename = ("https://github.com/pytorch/hub/raw/master/images/dog.jpg", "dog.jpg")
>>> urllib.request.urlretrieve(url, filename)
>>> img = Image.open(filename).convert('RGB')
>>> tensor = transform(img).unsqueeze(0) # transform and add batch dimension

獲取模型預測結果

>>> import torch
>>> with torch.inference_mode():
...     out = model(tensor)
>>> probabilities = torch.nn.functional.softmax(out[0], dim=0)
>>> print(probabilities.shape)
>>> # prints: torch.Size([1000])

獲取排名前 5 的預測類別名稱

>>> # Get imagenet class mappings
>>> url, filename = ("https://raw.githubusercontent.com/pytorch/hub/master/imagenet_classes.txt", "imagenet_classes.txt")
>>> urllib.request.urlretrieve(url, filename) 
>>> with open("imagenet_classes.txt", "r") as f:
...     categories = [s.strip() for s in f.readlines()]

>>> # Print 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())
>>> # prints class names and probabilities like:
>>> # [('Samoyed', 0.6425196528434753), ('Pomeranian', 0.04062102362513542), ('keeshond', 0.03186424449086189), ('white wolf', 0.01739676296710968), ('Eskimo dog', 0.011717947199940681)]

將模型名稱替換為您想要使用的變體，例如 densenet121。您可以在本頁頂部的模型摘要中找到 ID。

要使用此模型提取影像特徵，請遵循 timm 特徵提取示例，只需更改你想使用的模型名稱。

如何微調此模型？

你可以透過更改分類器（最後一層）來微調任何預訓練模型。

>>> model = timm.create_model('densenet121', pretrained=True, num_classes=NUM_FINETUNE_CLASSES)

要在自己的資料集上進行微調，你需要編寫一個訓練迴圈或修改 timm 的訓練指令碼以使用你的資料集。

如何訓練此模型？

你可以按照 timm 食譜指令碼來重新訓練一個新模型。

引用

@article{DBLP:journals/corr/HuangLW16a,
  author    = {Gao Huang and
               Zhuang Liu and
               Kilian Q. Weinberger},
  title     = {Densely Connected Convolutional Networks},
  journal   = {CoRR},
  volume    = {abs/1608.06993},
  year      = {2016},
  url       = {http://arxiv.org/abs/1608.06993},
  archivePrefix = {arXiv},
  eprint    = {1608.06993},
  timestamp = {Mon, 10 Sep 2018 15:49:32 +0200},
  biburl    = {https://dblp.org/rec/journals/corr/HuangLW16a.bib},
  bibsource = {dblp computer science bibliography, https://dblp.org}
}

@misc{rw2019timm,
  author = {Ross Wightman},
  title = {PyTorch Image Models},
  year = {2019},
  publisher = {GitHub},
  journal = {GitHub repository},
  doi = {10.5281/zenodo.4414861},
  howpublished = {\url{https://github.com/rwightman/pytorch-image-models}}
}

< > 在 GitHub 上更新