如何检查RGB图像是否只包含一种颜色？

I'm using Python and PIL.

我正在使用Python和PIL。

I have images in RGB and I would like to know those who contain only one color (say #FF0000 for example) or a few very close colors (#FF0000 and #FF0001).

我有RGB图像,我想知道那些只包含一种颜色(例如#FF0000)或几种非常接近的颜色(#FF0000和#FF0001)的图像。

I was thinking about using the histogram but it is very hard to figure out something with the 3 color bands, so I'm looking for a more clever algorithm.

我正在考虑使用直方图,但很难找出具有3个色带的东西,所以我正在寻找更聪明的算法。

Any ideas?

ImageStat module is THE answer! Thanks Aaron. I use ImageStat.var to get the variance and it works perfectly.

ImageStat模块就是答案!谢谢亚伦。我使用ImageStat.var来获得方差,它完美地运行。

Here is my piece of code:

这是我的一段代码:

from PIL import Image, ImageStat

MONOCHROMATIC_MAX_VARIANCE = 0.005

def is_monochromatic_image(src):
    v = ImageStat.Stat(Image.open(src)).var
    return reduce(lambda x, y: x and y < MONOCHROMATIC_MAX_VARIANCE, v, True)

3 个解决方案

#1

Try the ImageStat module. If the values returned by extrema are the same, you have only a single color in the image.

试试ImageStat模块。如果extrema返回的值相同,则图像中只有一种颜色。

#2

First, you should define a distance between two colors. Then you just have to verify for each pixel that it's distance to your color is small enough.

首先,您应该定义两种颜色之间的距离。然后你只需要验证每个像素与你的颜色的距离是否足够小。

#3

Here's a little snippet you could make use of :

这是一个你可以使用的小片段:


import Image

im = Image.open("path_to_image")
width,height = im.size

for w in range(0,width):
  for h in range(0,height):
     # this will hold the value of all the channels
     color_tuple = im.getpixel((w,h))
     # do something with the colors here

Maybe use a hash and store the tuples as the key and it's number of appearances as value?

也许使用哈希并将元组存储为密钥,并将它的出现次数作为值?

#1