如何生成远离值列表的随机值？

Question

我有以下透明图像

我想做的是将它们粘贴到具有特定颜色背景的图像上。背景的颜色是随机的，如下所示：

rand1, rand2, rand3 = (random.randint(0, 255),
                       random.randint(0, 255),
                       random.randint(0, 255))

background = Image.new('RGBA', png.size, (rand1, rand2, rand3))

alpha_composite = Image.alpha_composite(background, png)

不幸的是，有些徽标与背景色不协调。背景色有时接近徽标内部的颜色，这使得徽标部分或完全不可见。下面是一个示例，其中背景色几乎与Ubuntu徽标中的橙色相同：

我所做的是从每个徽标中获取所有颜色，并将它们保存在一个元组列表中，如下所示。这实际上是一个元组列表。我刚刚对其进行了编辑，以突出显示哪个嵌套元组列表属于哪个徽标：

Intel = [(0, 113, 197)]
Corsair = [(4, 7, 7)]
Google = [(66, 133, 244), (234, 67, 53), (251, 188, 5), (52, 168, 83), (0, 255, 255), (255, 128, 0), (255, 255, 0)]
Riot = [(209, 54, 57), (255, 255, 255), (226, 130, 132), (0, 0, 0)]

我想做的是使用上述信息随机选择背景颜色，这样就不会使徽标的任何部分不可见。我在征求有关这方面的策略建议

这是为徽标添加背景色的功能：

def logo_background(path):

    rand1, rand2, rand3 = (random.randint(0, 255),
                           random.randint(0, 255),
                           random.randint(0, 255))

    png = Image.open(path).convert('RGBA')
    colors = extcolors.extract_from_path(path)

    background = Image.new('RGBA', png.size, (rand1, rand2, rand3))

    alpha_composite = Image.alpha_composite(background, png)


    return alpha_composite

>>> extcolors.extract_from_path(path)
[((0, 113, 197), 25727), 56235]

# for the intel logo, which is just blue with transparent background

有些商标是完全黑色的。海盗船的标志是一个透明背景的全黑标志，但代码没有选择正确的背景

Answer 1

我认为使用像rgb这样的三分量向量机对于随机选择来说是困难的。我会先把它转换成hsv颜色系统（色调、饱和度、亮度）。然后，我们只需要担心色调，就可以使用random.choice从可能值的1D列表中选择一个值

Google = [(66, 133, 244), (234, 67, 53), (251, 188, 5), (52, 168, 83), (0, 255, 255), (255, 128, 0), (255, 255, 0)]
threshold = 0.1 #No hue value closer than threshold to a logo-color 

# convert to hsv
GoogleHsv = [colorsys.rgb_to_hsv(r/255.0, g/255.0, b/255.0) for r,g,b in Google] 
print("GoogleHsv:", GoogleHsv)

# list of possible hue-values that are at least threshold away from all logo-hue-values
choices = [x for x in np.linspace(0,1,201) if min([abs(x-h) for h,l,s in GoogleHsv]) > threshold] 
print("choices:", choices)

h = random.choice(choices)
l = random.random() # random lightness 
s = random.random() # random saturation
# you could also use constants for l,s to alway get a vibrant/dark color.

color = [int(x*255) for x in colorsys.hsv_to_rgb(h, l, s)] # converting back to rbg
print("color:", color)

希望这有帮助。祝你今天愉快

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编辑

对于您的函数，它将如下所示：

def logo_background(path):
    
    threshold = 0.1        
    png = Image.open(path).convert('RGBA')
    used_colors_rgb = extcolors.extract_from_path(path)[0]

    used_hsv = [colorsys.rgb_to_hsv(r/255.0, g/255.0, b/255.0) for (r,g,b), _ in used_colors_rgb] 
    choices = [x for x in np.linspace(0,1,201) if min([abs(x-h) for h,l,s in used_hsv]) > threshold] 
    h, l, s = random.choice(choices), (random.random()+1) / 2, (random.random()+1) / 2    
    color = [int(x*255) for x in colorsys.hsv_to_rgb(h, l, s)]
  
    background = Image.new('RGBA', png.size,tuple(color))
    alpha_composite = Image.alpha_composite(background, png)
    return alpha_composite
    
logo_background("google.png")