AttributeError：数据集对象没有属性“c”FastAI

Posted 2023-03-27

【中文标题】AttributeError：数据集对象没有属性“c”FastAI

【英文标题】：AttributeError: dataset object has no attribute 'c' FastAI

【发布时间】：2020-06-03 09:47:09

【问题描述】：

我正在尝试训练基于UNet 的ResNet 进行图像分割。我在csv 文件中有图像和遮罩图像的位置，这就是我创建自己的dataloader 的原因，如下所示：

X = list(df['input_img'])
y = list(df['mask_img'])

X_train, X_valid, y_train, y_valid = train_test_split(
     X, y, test_size=0.33, random_state=42)

class NumbersDataset():
    def __init__(self, inputs, labels):
        self.X = inputs
        self.y = labels

    def __len__(self):
        return len(self.X)

    def __getitem__(self, idx):
        img_train = cv2.imread(self.X[idx])
        img_mask = cv2.imread(self.y[idx])
        img_train = cv2.resize(img_train, (427,240), interpolation = cv2.INTER_LANCZOS4) 
        img_mask = cv2.resize(img_mask, (427,240), interpolation = cv2.INTER_LANCZOS4) 
        return img_train, img_mask

然后我在__main__ 函数中调用这个datagenerator：

if __name__ == '__main__':
    dataset_train = NumbersDataset(X_train, y_train)
    dataloader_train = DataLoader(dataset_train, batch_size=4, shuffle=True, num_workers=2)

    dataset_valid = NumbersDataset(X_valid, y_valid)
    dataloader_valid = DataLoader(dataset_valid, batch_size=4, shuffle=True, num_workers=2)

    datas = DataBunch(train_dl = dataloader_train, valid_dl = dataloader_valid)
    leaner = unet_learner(data = datas, arch = models.resnet34)

但我最终得到以下错误：

Traceback (most recent call last):
  File "dataset_test.py", line 70, in <module>
    leaner = unet_learner(data = datas, arch = models.resnet34)
  File "/home/sarvagya/miniconda3/envs/gr/lib/python3.6/site-packages/fastai/vision/learner.py", line 118, in unet_learner
    model = to_device(models.unet.DynamicUnet(body, n_classes=data.c, img_size=size, blur=blur, blur_final=blur_final,
  File "/home/sarvagya/miniconda3/envs/gr/lib/python3.6/site-packages/fastai/basic_data.py", line 122, in __getattr__
    def __getattr__(self,k:int)->Any: return getattr(self.train_dl, k)
  File "/home/sarvagya/miniconda3/envs/gr/lib/python3.6/site-packages/fastai/basic_data.py", line 38, in __getattr__
    def __getattr__(self,k:str)->Any: return getattr(self.dl, k)
  File "/home/sarvagya/miniconda3/envs/gr/lib/python3.6/site-packages/fastai/basic_data.py", line 20, in DataLoader___getattr__
    def DataLoader___getattr__(dl, k:str)->Any: return getattr(dl.dataset, k)

AttributeError: 'NumbersDataset' 对象没有属性 'c'

我尝试搜索，甚至尝试使用SegmentationItemList.from_df，但没有任何帮助。我在这里做错了什么？

【参考方案1】：

您应该将属性 c 添加到您的 NumbersDataset 中，如下所示：

def __init__(self, inputs, labels, c):
  self.inputs = inputs
  self.labels = labels
  self.c = c