将RGB转换为灰度python

Question

我已经将RGB图像转换为灰度图像，下面是代码

import numpy
import glob
import cv2
import csv
import math
import os
import string
from skimage.color import rgb2gray
from PIL import Image

mylist = [f for f in glob.glob("*.jpg")]

for imagefile in mylist:
    img_color = cv2.imread(imagefile)
    image = cv2.resize(img_color,(100,100),interpolation = cv2.INTER_AREA)
    img_gray = rgb2gray(image)
    img_gray.flatten()

我没有将新图像保存到我的当前文件夹中。谁能帮我这个忙。

Answer 1

我认为是因为skimage。你为什么不只使用opencv。

import numpy
import glob
import cv2
import csv
import math
import os
import string
from skimage.color import rgb2gray
from PIL import Image

mylist = [f for f in glob.glob("*.jpg")]

for imagefile in mylist:
    img_color = cv2.imread(imagefile)
    image = cv2.resize(img_color,(100,100),interpolation = cv2.INTER_AREA)
    img_gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    #img_gray = rgb2gray(image)
    img_gray.flatten()
    cv2.imwrite("gray"+imagefile,img_gray)

Answer 2

根据我的说法，使用Pillow进行此任务将是最有效的方法。

from PIL import Image
img = Image.open('image.png').convert('LA')
img.save('greyscale.png')

您可以参考https://stackoverflow.com/a/45338831/9851541
也可以尝试
import imageio
import numpy as np
import matplotlib.pyplot as plt

pic = imageio.imread('DemoImage.png')
gray = lambda rgb : np.dot(rgb[... , :3] , [0.299 , 0.587, 0.114]) 
gray = gray(pic)  
plt.imshow(gray, cmap = plt.get_cmap(name = 'gray'))