1. 识别二维码例程讲解#
1. 概述#
CanMV支持OpenMV算法,支持识别二维码,相关接口为find_qrcodes
2. 示例#
本示例设置摄像头输出640x480灰度图像,使用image.find_qrcodes
来识别二维码
小技巧
如果识别成功率低,可尝试修改摄像头输出的mirror和flip设置
# QRCode Example
#
# This example shows the power of the CanMV Cam to detect QR Codes.
import time, os, gc, sys
from media.sensor import *
from media.display import *
from media.media import *
DETECT_WIDTH = 640
DETECT_HEIGHT = 480
sensor = None
try:
# construct a Sensor object with default configure
sensor = Sensor(width = DETECT_WIDTH, height = DETECT_HEIGHT)
# sensor reset
sensor.reset()
# set hmirror
# sensor.set_hmirror(False)
# sensor vflip
# sensor.set_vflip(False)
# set chn0 output size
sensor.set_framesize(width = DETECT_WIDTH, height = DETECT_HEIGHT)
# set chn0 output format
sensor.set_pixformat(Sensor.GRAYSCALE)
# use hdmi as display output, set to VGA
# Display.init(Display.LT9611, width = 640, height = 480, to_ide = True)
# use hdmi as display output, set to 1080P
# Display.init(Display.LT9611, width = 1920, height = 1080, to_ide = True)
# use lcd as display output
# Display.init(Display.ST7701, to_ide = True)
# use IDE as output
Display.init(Display.VIRT, width = DETECT_WIDTH, height = DETECT_HEIGHT, fps = 100)
# init media manager
MediaManager.init()
# sensor start run
sensor.run()
fps = time.clock()
while True:
fps.tick()
# check if should exit.
os.exitpoint()
img = sensor.snapshot()
for code in img.find_qrcodes():
rect = code.rect()
img.draw_rectangle([v for v in rect], color=(255, 0, 0), thickness = 5)
img.draw_string_advanced(rect[0], rect[1], 32, code.payload())
print(code)
# draw result to screen
Display.show_image(img)
gc.collect()
print(fps.fps())
except KeyboardInterrupt as e:
print(f"user stop")
except BaseException as e:
print(f"Exception '{e}'")
finally:
# sensor stop run
if isinstance(sensor, Sensor):
sensor.stop()
# deinit display
Display.deinit()
os.exitpoint(os.EXITPOINT_ENABLE_SLEEP)
time.sleep_ms(100)
# release media buffer
MediaManager.deinit()
提示
具体接口定义请参考 find_qrcodes