如何将从URL检索的图像放入图像小部件

Question

我找到了这段代码，并且它能够正常工作，可以检索并显示图像。

import IPython
url = 'https://newevolutiondesigns.com/images/freebies/colorful-background-14.jpg'
IPython.display.Image(url, width = 250)

但我实际上想把图像放入图像小部件中，所以我尝试了这样做：

import IPython
from ipywidgets import widgets

url = 'https://newevolutiondesigns.com/images/freebies/colorful-background-14.jpg'
image = IPython.display.Image(url, width = 300)

widgets.Image(
  value=image,
  format='jpg', 
  width=300,
  height=400,
)

但我遇到了这个错误：

---------------------------------------------------------------------------
TraitError                                Traceback (most recent call last)
<ipython-input-45-5011b6084128> in <module>()
     57     format='jpg',
     58     width=300,
---> 59     height=400,
     60 )

________________________________________
7 frames
________________________________________
/usr/local/lib/python3.6/dist-packages/traitlets/traitlets.py in error(self, obj, value)
    623             e = "The '%s' trait must be %s, but a value of %r was specified." \
    624                 % (self.name, self.info(), repr_type(value))
--> 625         raise TraitError(e)
    626 
    627     def get_metadata(self, key, default=None):

TraitError: The 'value' trait of an Image instance must be a bytes object, but a value of 
<IPython.core.display.Image object> <class 'IPython.core.display.Image'> was specified.

那么，我的问题是：我该如何将图片放入图像小部件中？

- Iman

Answer 1

首先感谢你提供的最小化示例。

错误提示告诉你需要做什么。你需要将图像文件的 bytes 传递给 ipywidgets.Image 类。通过从你的 Ipython.display.Image 实例中传递 image.data 来实现此功能。

import IPython
from ipywidgets import widgets

url = 'https://newevolutiondesigns.com/images/freebies/colorful-background-14.jpg'
image = IPython.display.Image(url, width = 300)

widgets.Image(
  value=image.data,
  format='jpg', 
  width=300,
  height=400,
)

或者使用类似于requests的包获取图片的bytes，并将其传递给widgets.Image，无需使用Ipython.display.Image实例。

- ac24