Python:处理具有一百万个图像的文件夹而不会出错

Question

def preprocess_image(path_to_images):
    print("preprocessing images..")
    files = os.listdir(path_to_images)
    for f in files:
        im = Image.open(os.path.join(path_to_images, f))
        im = im.convert("RGBA")

        datas = im.getdata()
        newData = []
        for item in datas:
            if item[0] == 255 and item[1] == 255 and item[2] == 255:
                newData.append((255, 255, 255, 0))
            else:
                newData.append(item)
        im.putdata(newData)
        im.save(os.path.join(path_to_images, f),"PNG")

你好.因此,上面的代码应该删除文件夹中每个图像的背景.当我处理10个jpg图像的文件夹时,工作完全正常,但如果我使用包含12000个图像的文件夹运行它,我会收到以下错误:

Traceback (most recent call last):
  File "test1.py", line 28, in <module>
    preprocess_image("train_images" )
  File "test1.py", line 9, in preprocess_image
    im = Image.open(os.path.join(path_to_images, f))
  File "/Library/Python/2.7/site-packages/PIL/Image.py", line 2452, in open
    % (filename if filename else fp))
IOError: cannot identify image file 'train_images/.DS_Store'

带有图像的文件夹称为"train_images",我不知道.DS_Store来自哪里.

我非常感谢你的帮助.

Answer 1

.DS_Store是一个由mac文件系统创建的文件(当你用finder打开一个目录时)当你走过目录时你应该忽略它

try:
 im = Image.open(os.path.join(path_to_images, f))
except:
 print 'fail to read', path_to_images

• 您可以添加try和except块,如上例所示
• 要么 if f != '.DS_Store'
• 拆分以检查文件扩展名是否为图像 name, ext = 'image.jpg'.split(".") if ext in ['jpg', 'png' ... ]