scrapy生成图片缩略图

ITEM_PIPELINES = {
   'gamesky.pipelines.JiandanPipeline': 1,
}
IMAGES_STORE='E:/gamesky'
DOWNLOAD_DELAY = 0.25
IMAGES_THUMBS = {#缩略图的尺寸，设置这个值就会产生缩略图
    'small': (50, 50),
    'big': (200, 200),
}