V831

Preface

A qualified camera , It must be able to recognize QR code .

One 、 QR code recognition character

#!/usr/bin/python3
from maix import display, camera 

while True:
    t = camera.capture()
    mks = t.find_qrcodes()
    for mk in mks:
      # Outline data 
      X = mk['x']
      Y = mk['y']
      W = mk['w']
      H = mk['h']
      
      # QR code information 
      string = mk['payload']

      # Inner frame data 
      x1,y1 = mk['corners'][0]   # Access the list of dictionaries 
      x2,y2 = mk['corners'][1]
      x3,y3 = mk['corners'][2]
      x4,y4 = mk['corners'][3]
      
      # Draw frame 
      t.draw_rectangle(X, Y, X + W, Y + H, color=(0, 0, 255), thickness = 2) 
      # Print information 
      t.draw_string(int(X) , int(Y - 35) , str(string), scale = 2.0, color = (255, 0, 0), thickness = 2)  # Inner frame ID
      # Draw the inner frame 
      t.draw_line(x1, y1, x2, y2, color = (0, 255, 0), thickness = 3)  
      t.draw_line(x2, y2, x3, y3, color = (0, 255, 0), thickness = 3)  
      t.draw_line(x3, y3, x4, y4, color = (0, 255, 0), thickness = 3)  
      t.draw_line(x4, y4, x1, y1, color = (0, 255, 0), thickness = 3)  

    display.show(t)
    

Look directly at the code ,find_qrcodes()、 string = mk[‘payload’] these 831 All have been sealed for us , You can use it directly

But in the later test , It is found that Chinese cannot be recognized , Will report garbled code

So how to solve it

Two 、 Two dimensional code recognizes Chinese characters

1. Load Chinese font

image.load_freetype(path="/home/res/sans.ttf")

831 There is a built-in Chinese font , We just need to load it , then image You can display it

2. Complete code

#!/usr/bin/python3
from maix import display, camera,image
image.load_freetype(path="/home/res/sans.ttf")
while True:
    t = camera.capture()
    mks = t.find_qrcodes()
    for mk in mks:
      # Outline data 
      X = mk['x']
      Y = mk['y']
      W = mk['w']
      H = mk['h']
      
      # QR code information 
      string = mk['payload']

      # Inner frame data 
      x1,y1 = mk['corners'][0]   # Access the list of dictionaries 
      x2,y2 = mk['corners'][1]
      x3,y3 = mk['corners'][2]
      x4,y4 = mk['corners'][3]
      
      # Draw frame 
      t.draw_rectangle(X, Y, X + W, Y + H, color=(0, 0, 255), thickness = 2) 
      # Print information 
      t.draw_string(int(X) , int(Y - 35) , str(string), scale = 2.0, color = (255, 0, 0), thickness = 2)  # Inner frame ID
      # Draw the inner frame 
      t.draw_line(x1, y1, x2, y2, color = (0, 255, 0), thickness = 3)  
      t.draw_line(x2, y2, x3, y3, color = (0, 255, 0), thickness = 3)  
      t.draw_line(x3, y3, x4, y4, color = (0, 255, 0), thickness = 3)  
      t.draw_line(x4, y4, x1, y1, color = (0, 255, 0), thickness = 3)  

    display.show(t)
    

summary

Introduce the meaning of several key values .‘x’ , ‘y’ , ‘w’ , ‘h’ The values returned by the key values are the upper left corner of the outer frame x Coordinates and y Coordinates and the length and width of the outer frame . And key value ‘payload’ The returned value is the information of QR code .