Python OpenCV實現(xiàn)基本圖形繪制

import cv2 as cv
import numpy as np 

#(400,600,3)分別是寬、高、通道數(shù)
canvas = np.zeros((400,600,3),dtype=np.uint8)+255

#畫一條縱向正中央的黑色分界線,(300,0)分別是寬、高
cv.line(canvas,(300,0),(300,399),(0,0,0,),2)

#畫一條右半部分畫面以199為界的橫向分界線
cv.line(canvas,(300,199),(599,199),(0,0,0,),2)

# 左半部分的右下角畫個紅色的圓
cv.circle(canvas, (150, 300), 88, (0, 0, 255), 5) #(80, 300), 100-》圓心，半徑

# 左半部分的左下角畫個藍色的矩形 ，(10, 10), (60, 60) 左上角坐標(biāo), 右下角坐標(biāo),
cv.rectangle(canvas, (10, 300), (50, 390), (255, 0, 0), thickness=3) 

# 定義兩個三角形，并執(zhí)行內(nèi)部綠色填充
triangles = np.array([
    [(150, 240), (95, 333), (205, 333)],
    [(60, 160), (20, 217), (100, 217)]])
cv.fillPoly(canvas, triangles, (0, 255, 0))

# 畫一個黃色五角星
# 第一步通過旋轉(zhuǎn)角度的辦法求出五個頂點
phi = 4 * np.pi / 5
rotations = [[[np.cos(i * phi), -np.sin(i * phi)], [i * np.sin(phi), np.cos(i * phi)]] for i in range(1, 5)]
pentagram = np.array([[[[0, -1]] + [np.dot(m, (0, -1)) for m in rotations]]], dtype=np.float)
 
# 定義縮放倍數(shù)和平移向量把五角星畫在左半部分畫面的上方
pentagram = np.round(pentagram * 80 + np.array([160, 120])).astype(np.int)

# 將5個頂點作為多邊形頂點連線，得到五角星
cv.polylines(canvas, pentagram, True, (0, 255, 255), 9)

# 按像素為間隔從左至右在畫面右半部份的上方畫出HSV空間的色調(diào)連續(xù)變化
for x in range(302, 600):
    color_pixel = np.array([[[round(180*float(x-302)/298), 255, 255]]], dtype=np.uint8)
    line_color = [int(c) for c in cv.cvtColor(color_pixel, cv.COLOR_HSV2BGR)[0][0]]
    cv.line(canvas, (x, 0), (x, 197), line_color)

# 如果定義圓的線寬大于半徑，則等效于畫圓點，隨機在畫面右下角的框內(nèi)生成坐標(biāo)
np.random.seed(42)
n_pts = 30
pts_x = np.random.randint(310, 590, n_pts)   #x范圍
pts_y = np.random.randint(210, 390, n_pts)   #y范圍
pts = zip(pts_x, pts_y)
 
# 畫出每個點，顏色隨機
for pt in pts:
    pt_color = [int(c) for c in np.random.randint(0, 255, 3)]
    cv.circle(canvas, pt, 3, pt_color, 5)

# OpenCV-Python在圖片上輸出中文
# 在Python中，可以借助PIL(Python Imaging Library)模塊實現(xiàn)
from PIL import Image, ImageDraw, ImageFont
 
# 圖像從OpenCV格式轉(zhuǎn)換成PIL格式
pil_img = cv.cvtColor(canvas,cv.COLOR_BGR2RGB)#cv2和PIL中顏色的hex碼的儲存順序不同，需轉(zhuǎn)RGB模式
pilimg = Image.fromarray(pil_img)#Image.fromarray()將數(shù)組類型轉(zhuǎn)成圖片格式，與np.array()相反
draw = ImageDraw.Draw(pilimg)#PIL圖片上打印漢字
 
#參數(shù)1：字體文件路徑，參數(shù)2：字體大??；Windows系統(tǒng)“simhei.ttf”默認存儲在路徑：C:/Windows/Fonts中
font = ImageFont.truetype("SIMLI.TTF",30,encoding="utf-8")
 
draw.text((0,0),"打印的文字 English",(255,0,0),font=font)
cv2img = cv.cvtColor(np.array(pilimg),cv.COLOR_RGB2BGR)#將圖片轉(zhuǎn)成cv2.imshow()可以顯示的數(shù)組格式

#展示繪制的圖形
cv.namedWindow('Basic Graph',cv.WINDOW_NORMAL)
cv.imshow('Basic Graph',canvas)

#保存繪制的圖像
cv.imwrite('C:/Users/Administrator/Desktop/New_Study/IMAGE/Result_img/Basic_Graph.jpg',canvas)

cv.waitKey()