Python Wand将tiff更改为min-is-white

I need to convert files to tiff where photometric is set "min-is-white" (white is zero) to comply with the required standards. I'm using Wand to interact with Photomagick but every I save a bilevel tiff file, it creates a min-is-black.

我需要将文件转换为tiff,其中光度计设置为“min-is-white”(白色为零)以符合所需标准。我正在使用Wand与Photomagick进行交互,但每次我保存一个双层tiff文件,它会创建一个min-is-black。

How can I get Wand to saves it where White is Zero? Is it even possible?

如何将魔杖保存在白色为零的地方?它甚至可能吗?

1 个解决方案

#1

Mark's comments are correct. You need to set the -define property for ImageMagick.

马克的评论是正确的。您需要为ImageMagick设置-define属性。

For wand, you'll have to extent the core wand.api.library to connect MagickWand's C-API MagickSetOption method.

对于魔杖,你必须扩展核心wand.api.library以连接MagickWand的C-API MagickSetOption方法。

from ctypes import c_void_p, c_char_p
from wand.api import library
from wand.image import Image

# Tell python about the MagickSetOption method
library.MagickSetOption.argtypes = [c_void_p,  # MagickWand * wand
                                    c_char_p,  # const char * option
                                    c_char_p]  # const char * value

# Read source image
with Image(filename="/path/to/source.tiff") as image:
    # -define quantum:polarity=min-is-white
    library.MagickSetOption(image.wand,          # MagickWand
                            "quantum:polarity",  # option
                            "min-is-white")      # value
    # Write min-is-white image
    image.save(filename="/path/to/min-is-white.tiff")

You can verify the resulting image with the identify utility.

您可以使用标识实用程序验证生成的图像。

identify -verbose /path/to/min-is-white.tiff | grep photometric
#=> tiff:photometric: min-is-white

#1