python 灰度图像转彩色_有没有好的色彩映射使用python的PIL将灰度图像转换为彩色图像？...

我想出了@ImportanceOfBeingErnest(

How to convert Numpy array to PIL image applying matplotlib colormap)提到的重复答案

import matplotlib as mpl

import matplotlib.pyplot as plt

import matplotlib.image as mpimg

import numpy as np

import timeit

from PIL import Image

def pil_test():

cm_hot = mpl.cm.get_cmap('hot')

img_src = Image.open('test.jpg').convert('L')

img_src.thumbnail((512,512))

im = np.array(img_src)

im = cm_hot(im)

im = np.uint8(im * 255)

im = Image.fromarray(im)

im.save('test_hot.jpg')

def rgb2gray(rgb):

return np.dot(rgb[:,:,:3], [0.299, 0.587, 0.114])

def plt_test():

img_src = mpimg.imread('test.jpg')

im = rgb2gray(img_src)

f = plt.figure(figsize=(4, 4), dpi=128)

plt.axis('off')

plt.imshow(im, cmap='hot')

plt.savefig('test2_hot.jpg', dpi=f.dpi)

plt.close()

t = timeit.timeit(pil_test, number=30)

print('PIL: %s' % t)

t = timeit.timeit(plt_test, number=30)

print('PLT: %s' % t)

表现结果如下：

PIL: 1.7473899199976586

PLT: 10.632971412000188

他们都给我类似的结果与热色地图.