改变图像的颜色

Question

用 RGB 值改变整个图像颜色的最简单方法是什么？我试过 wand，但是 documentation 对我来说意义不大，我只能在 Pillow 文档中找到更改颜色强度的方法。

我在网上尝试了多种解决方案，但是它们要么没有达到我的要求，要么已经过时并且不起作用。

我想要它让整个图像着色，我可以通过更改 RGB 颜色来控制色调，有点像这样:

http://cdn.makeuseof.com/wp-content/uploads/2012/11/Folder-Colorizer-Color-Manager.jpg?69fac7

我可以自己实现轮子，但是实际改变颜色的部分让我很困惑。希望这将是一个简单的解决方案。 :)

Answer 1

import Image
import numpy as nump

img = Image.open('snapshot.jpg')

# In this case, it's a 3-band (red, green, blue) image
# so we'll unpack the bands into 3 separate 2D arrays.
 r, g, b = nump.array(img).T

  # Let's make an alpha (transparency) band based on where blue is < 100
  a = nump.zeros_like(b)
  a[b < 100] = 255

 # Random math... This isn't meant to look good...
 # Keep in mind that these are unsigned 8-bit integers, and will overflow.
   # You may want to convert to floats for some calculations.
  r = (b + g) * 5

    # Put things back together and save the result...
  img = Image.fromarray(nump.dstack([item.T for item in (r,g,b,a)]))

   img.save('out.png')

像这样，你可以使用numpy。

或

你可以使用 Pillow。 [lnk] (https://pillow.readthedocs.org/)

Answer 2

这是我的 other answer. It's almost identical except for the imports which had to be changed in order to use the pillow 分支中 PIL 代码的 Python 3 版本（因为它只支持 Python 3）。我所做的其他更改是将 print 语句更改为函数调用，其中 map() 函数用于创建 luts 查找 table 变量。

from PIL import Image
from PIL.ImageColor import getcolor, getrgb
from PIL.ImageOps import grayscale

def image_tint(src, tint='#ffffff'):
    if Image.isStringType(src):  # file path?
        src = Image.open(src)
    if src.mode not in ['RGB', 'RGBA']:
        raise TypeError('Unsupported source image mode: {}'.format(src.mode))
    src.load()

    tr, tg, tb = getrgb(tint)
    tl = getcolor(tint, "L")  # tint color's overall luminosity
    if not tl: tl = 1  # avoid division by zero
    tl = float(tl)  # compute luminosity preserving tint factors
    sr, sg, sb = map(lambda tv: tv/tl, (tr, tg, tb))  # per component
                                                      # adjustments
    # create look-up tables to map luminosity to adjusted tint
    # (using floating-point math only to compute table)
    luts = (tuple(map(lambda lr: int(lr*sr + 0.5), range(256))) +
            tuple(map(lambda lg: int(lg*sg + 0.5), range(256))) +
            tuple(map(lambda lb: int(lb*sb + 0.5), range(256))))
    l = grayscale(src)  # 8-bit luminosity version of whole image
    if Image.getmodebands(src.mode) < 4:
        merge_args = (src.mode, (l, l, l))  # for RGB verion of grayscale
    else:  # include copy of src image's alpha layer
        a = Image.new("L", src.size)
        a.putdata(src.getdata(3))
        merge_args = (src.mode, (l, l, l, a))  # for RGBA verion of grayscale
        luts += tuple(range(256))  # for 1:1 mapping of copied alpha values

    return Image.merge(*merge_args).point(luts)

if __name__ == '__main__':
    import os
    import sys

    input_image_path = 'Dn3CeZB.png'
    print('tinting "{}"'.format(input_image_path))

    root, ext = os.path.splitext(input_image_path)
    suffix = '_result_py{}'.format(sys.version_info[0])
    result_image_path = root+suffix+ext

    print('creating "{}"'.format(result_image_path))
    result = image_tint(input_image_path, '#383D2D')
    if os.path.exists(result_image_path):  # delete any previous result file
        os.remove(result_image_path)
    result.save(result_image_path)  # file name's extension determines format

    print('done')

这是之前和之后的图片。 test image 和 tint 颜色与您遇到问题时所说的相同。结果看起来与你的 Py2 版本非常相似，对我来说还可以……我是不是漏掉了什么？

改变图像的颜色

Changing colour of an image

image

colors

python-3.x

pillow

wand