一 opencv
import cv2 as cv # load img = cv.imread(imagepath) # shape=(height, width, channel) h,w,c = img.shape # show cv.imshow('window_title', img) # save cv.imwrite(savepath, img)
二 matplotlib
import matplotlib.pyplot as plt # plt for displaying an image import matplotlib.image as mpimg # mpimg for reading image Import numpy NP AS # Load img = mpimg.imread ( 'dog.jpg') # this time was already img a np.array, and it can be disposable # height, width, Channel = (360, 480,. 3) H, W, C = img.shape # Show plt.imshow (IMG) # display picture plt.axis ( 'off') # coordinate axes are not displayed plt.show () # save # applicable to any image stored matplotlib drawn, corresponding to a ScreenCapture plt.savefig ( 'fig_dog.png')
Note:
(1) plt.imshow (image) of the image data type allows type np.array
imshow () function format: matplotlib.pyplot.
imshow
(X-, CMap = None)
X: image or array to be drawn.
cmap: Color Atlas (colormap), plotted as a default RGB (A) color space.
Other optional color map list below:
Are used more gray, jet, such as:
plt.imshow(image,plt.cm.gray) plt.imshow(img,cmap=plt.cm.jet)
(2) mpimg provides both load image function imread
, but also provides the function to save the imageimsave
(. 3) plt.savefig function may be displayed in the image saved in fig
Extension: display image scaling
Misc SciPy Import from lena_new_sz = misc.imresize (IMG, 0.5) # If the second parameter is an integer, or percentage, if a tuple, compared with the size of the output image plt.imshow (img_new_sz) plt.axis ( 'OFF' ) plt.show ()
Three PIL
PIL display image is loaded in two ways:
First: call the operating system built-in picture browser to open the picture
the PIL Import Image from # Load IM = Image.open ( 'cat.jpg') # Show im.show () "" " # apos size W Back Image, H = (480, 360) W, H = img.size # the PIL .JpegImagePlugin.JpegImageFile of the type (img) the Save method # direct calls to the Image class img.save ( 'new_cat.png') "" "
Second: let the program to draw pictures
from PIL import Image import matplotlib.pyplot as plt img=Image.open('/home/wanghao/Pictures/001.jpg') plt.figure("head") plt.imshow(img) plt.show()
Some rendering and display pictures summary of some commonly used functions:
Function name | Features | Call format |
figure | Create a display window | plt.figure(num=1,figsize=(8,8) |
imshow | Draw pictures | plt.imshow(image) |
show | Display window | plt.show() |
subplot | Allotting map | plt.subplot (2,2,1) |
title | FIG sub-title set (in combination with the subplot) | plt.title('origin image') |
axis | Whether sitting ruler | plt.axis ( 'off') |
subplots | Creates a window with multiple sub-graph | fig,axes=plt.subplots(2,2,figsize=(8,8)) |
ravel | FIG variables for each sub-set | ax0,ax1,ax2,ax3=axes.ravel() |
set_title | FIG sub-title set (in combination with the axes) | ax0.set_title('first window') |
tight_layout | Automatically adjusting the display layout submap | plt.tight_layout() |
Reference: https://blog.csdn.net/u010472607/article/details/78855816