图片上画线条
import sys
from PIL import Image,ImageDraw
im = Image.open("th.png")
draw = ImageDraw.Draw(im) #实例化一个对象
draw.line((0, 0) + im.size, fill=128, width=5) #线的起点和终点，线宽
draw.line((0, im.size[1], im.size[0], 0), fill=128)
draw.line((0,im.size[1]/2)+(im.size[0]/2,im.size[1]), fill=128, width=5)
im.show()
图片上写字
from PIL import Image, ImageDraw, ImageFont
# get an image
base = Image.open('th.jpg').convert('RGBA')
# make a blank image for the text, initialized to transparent text color
txt = Image.new('RGBA', base.size, (255,255,255,0))
# get a font 需要在C:WindowsFonts拷贝一份字体文件 当前脚本路径下
fnt = ImageFont.truetype('cambriAI.ttf', 40)
# get a drawing context
d = ImageDraw.Draw(txt)
# draw text, half opacity
d.text((10,10), "Hello", font=fnt, fill=(255,255,255,128))
# draw text, full opacity
d.text((10,60), "World", font=fnt, fill=(255,255,255,255))
fillcolor = "#ff0000" #字体颜色
d.text((base.size[0]-20,10), "4", font=fnt, fill=fillcolor)
out = Image.alpha_composite(base, txt)
out.show()
参考官方文档 https://pillow.readthedocs.io/en/stable/reference/Image.html
补充知识：python对图像中的人脸进行画框(人脸的位置数据记录在记事本文件中)
我就废话不多说了，大家还是直接看代码吧！
import numpy as py
import os
import cv2 as cv
with open('labelFaceData.txt','r')as fp:#打开记录了数据的记事本文件
pictureNumber = 0#用来记录照片的数量
while 1:
count = 1
line = fp.readline()#读取文件中每一行的数据
if not line:#如果读取失败则退出
break
pictureNumber+=1#图片数加1
str1 = line.split()#用一个数组以字符串的形式储存文件中的数据
img = cv.inread(str[0])#str[0]中存放的是要读取的图片地址，用cv.inread读取它
faceNumber = (len(str1)-1)/16#用来记录人脸的总数
for i in reage(faceNumber):#用for循环对人脸进行画框
x = int(str1[count+1])#x,y,w,h为画框需要的点
y = int(str1[count+2])
w = int(str1[count+3])
h = int(str1[count+4])
cv.rectangle(img,(x,y),(x+w,y+h),(255,0,0),3,4,0)#用rectangle对图像进行画框
count+=16
#cv.namedWindow(str[0],0)
#cv.imshow(str[0],img);
#cv.waitKey(0)
cv.imwrite("./result/image1_"+str(pictureNumber)+".jpg",img)#保存图片
fp.close()
