python - 魔杖：Image.composite 将 bg-image 变为黑色

Question

我有个问题。以下代码确实有效，它结合了两个图像。但是最终合成中的背景图像是完全黑色的。

任何猜测，这里有什么问题？

from wand.image import Image

with Image(filename=bgimage) as back:
    with Image(filename=qrcode) as front:
        with Image(width=back.width, height=back.height) as new_image:
            new_image.composite(front, left=1000, top=900)
            new_image.save(filename=qr_output)

Answer 1

尝试删除该new_image部分，并简化一切。

with Image(filename="wizard:") as back:
  with Image(filename="rose:") as front:
    back.composite(front,
                   top=back.height-front.height,
                   left=back.width-front.width)
    back.save(filename="/tmp/output.png")

如果您尝试重用back实例，请利用wand.image.Image.clone

with Image(filename=bgimage) as back:
  with Image(filename=qrcode) as front:
     with back.clone() as new_image:
       new_image.composite(front, left=1000, top=900)
       new_image.save(filename=qr_output)