我正在通过PILLOW在我的烧瓶后端调整图像大小，但是当它到达代码行.resize时，它会失败吗？

Question

我正在尝试调整上传文件的大小。到目前为止，我确信图像已正确加载，并创建了PILLOW图像类。它运行我的调整大小脚本，但它总是停在.resize代码上...

我在桌面上运行代码（不在服务器上），图像调整大小有效，但是当我将调整大小脚本与通过POST上传的图像结合使用时，它不起作用并显示500错误。这是怎么回事？

我在imageresizer代码之后使用了print imageThumbnail.size并获得了AttributeError: 'NoneType' object has no attribute 'size'

def imageResizer(im, pixellimit):

  width, height = im.size

  if width > height:
    #Land scape mode. Scale to width.

    aspectRatio = float(height)/float(width)
    Scaledwidth = pixellimit
    Scaledheight = int(round(Scaledwidth * aspectRatio))
    newSize = (Scaledwidth, Scaledheight)
  elif height > width:
    #Portrait mode, Scale to height.
    aspectRatio = float(width)/float(height)
    Scaledheight = pixellimit
    Scaledwidth = int(round(Scaledheight * aspectRatio))
    newSize = (Scaledwidth, Scaledheight)

  #FAILS RIGHT HERE... I double checked by writing print flags all over, and it so happens nothing past this line gets written
  imageThumbnail = im.resize(newSize)

  return imageThumbnail

这是FLask框架的一部分。

file = request.files['file']
    location = str(args['lat']) + str(args['lon'])
    location = location.replace('.','_')
    GUID = datetime.strftime(datetime.now(), '%Y%m%d%H%M%S') + location
    datetimeEntry = datetime.strftime(datetime.now(), '%Y-%m-%d %H:%M:%S')
    fullFileName = GUID + '.' + file.filename.rsplit('.', 1)[1]
    if file and allowed_file(file.filename):
      filename = secure_filename(file.filename)

      image = Image.open(file)
      imageThumbnail = imageResizer(image, 800)
      #NOTHING PAST THIS POINT GETS EXECUTED
      imageThumbnailName = GUID + "thumb" + '.' + file.filename.rsplit('.', 1)[1]
      imageThumbnailName.save(os.path.join(app.config['UPLOAD_FOLDER'], imageThumbnailName))
      file.save(os.path.join(app.config['UPLOAD_FOLDER_LARGE_IMAGES'], fullFileName))

Answer 1

问题是你正试图打开：

file = request.files['file']
image = Image.open(file)

file不是一个实际的文件，而是一些带有上传信息的元数据对象。你应该做的是：

image = Image.open(file.stream)