数据挖掘 - 如何下载 COCO 数据集图像？ - 吾爱随笔录

我正在尝试使用以下 COCO API 命令下载 COCO 数据集图像：

from pycocotools.coco import COCO
import requests
catIds = COCO.getCatIds(catNms=['person','dog', 'car'])

...但我收到以下错误消息。知道为什么会这样吗？

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-42-9cc4e2f62a0e> in <module>
----> 1 catIds = COCO.getCatIds(catNms=['person','dog', 'car'])

TypeError: getCatIds() missing 1 required positional argument: 'self'

以前，我使用这些说明配置了 pycocotools 。

编辑：

还有一些奇怪的错误信息。查看代码似乎没有“人”、“狗”或“汽车”这样的类别。为什么会这样？

我的代码：

a = COCO()  
catIds = a.getCatIds(catNms=['person','dog', 'car'])

收到错误信息：

---------------------------------------------------------------------------
KeyError                                  Traceback (most recent call last)
<ipython-input-12-57400207fde1> in <module>
      1 a = COCO() # calling init
----> 2 catIds = a.getCatIds(catNms=['person','dog', 'car'])

~\Anaconda3\lib\site-packages\pycocotools\coco.py in getCatIds(self, catNms, supNms, catIds)
    171             cats = self.dataset['categories']
    172         else:
--> 173             cats = self.dataset['categories']
    174             cats = cats if len(catNms) == 0 else [cat for cat in cats if cat['name']          in catNms]
    175             cats = cats if len(supNms) == 0 else [cat for cat in cats if cat['supercategory'] in supNms]

KeyError: 'categories'

从文件'cocoapi/PythonAPI/pycocotools/coco.py'中提取：

from pycocotools.coco import COCO # After downloading images from http://cocodataset.org/#download # Define location of annotations dataDir = '..' dataType = 'val2017' annFile = f'{dataDir}/annotations/instances_{dataType}.json' # Create instance coco = COCO(annFile) # Filter for specific categories catIds = coco.getCatIds(catNms=['person','dog', 'car'])