您正在尝试将图片尺寸调整为比原尺寸更大的尺寸，这是正常的，您可以放松质量。

You are trying to resize an image to a larger size than the original, it is normal that you loose quality.

要将图像尺寸调整为更小的尺寸，您可以查看我创建的这个模块： python-image-resize

To resize you image to a smaller size, you may have a look at this module I created: python-image-resize