前言
本文主要介绍在OpenCV用使用双目摄像头,包括:打开单目摄像头、设置摄像头参数、拍照、录制视频。
环境:编程语言:Python3 主要依赖库:OpenCV3.x 或 OpenCV4.x
双目摄像头
双目同步摄像头,两个镜头共用一个设备ID,左右摄像机同一频率。这款摄像头分辨率支持2560*960或以上。
思路流程
1、由于两个镜头共用一个设备ID,打开摄像头时使用cv2.VideoCapture()函数,只需打开一次。区别有的双目摄像头是左右镜头各用一个设备ID,需要打开两次cv2.VideoCapture(0),cv2.VideoCapture(1)。
2、双目摄像头的总分辨率是由左右镜头组成的,比如:左右摄像机总分辨率1280x480;分割为左相机640x480、右相机640x480
为了方便理解画了张草图;图中的“原点”是图像像素坐标系的原点。
3、分割后,左相机的分辨率:高度 0:480、宽度 0:640
右相机的分辨率:高度 0:480、宽度 640:1280
4、转换为代码后
# 读取摄像头数据 ret, frame = camera.read() #裁剪坐标为[y0:y1, x0:x1] HEIGHT * WIDTH left_frame = frame[0:480, 0:640] right_frame = frame[0:480, 640:1280] cv2.imshow("left", left_frame) cv2.imshow("right", right_frame)
1)分辨率1280x480
源代码:
# -*- coding: utf-8 -*- import cv2 import time AUTO = False # 自动拍照,或手动按s键拍照 INTERVAL = 2 # 自动拍照间隔 cv2.namedWindow("left") cv2.namedWindow("right") camera = cv2.VideoCapture(0) # 设置分辨率 左右摄像机同一频率,同一设备ID;左右摄像机总分辨率1280x480;分割为两个640x480、640x480 camera.set(cv2.CAP_PROP_FRAME_WIDTH,1280) camera.set(cv2.CAP_PROP_FRAME_HEIGHT,480) counter = 0 utc = time.time() folder = "./SaveImage/" # 拍照文件目录 def shot(pos, frame): global counter path = folder + pos + "_" + str(counter) + ".jpg" cv2.imwrite(path, frame) print("snapshot saved into: " + path) while True: ret, frame = camera.read() # 裁剪坐标为[y0:y1, x0:x1] HEIGHT*WIDTH left_frame = frame[0:480, 0:640] right_frame = frame[0:480, 640:1280] cv2.imshow("left", left_frame) cv2.imshow("right", right_frame) now = time.time() if AUTO and now - utc >= INTERVAL: shot("left", left_frame) shot("right", right_frame) counter += 1 utc = now key = cv2.waitKey(1) if key == ord("q"): break elif key == ord("s"): shot("left", left_frame) shot("right", right_frame) counter += 1 camera.release() cv2.destroyWindow("left") cv2.destroyWindow("right")
补充理解
OpenCV有VideoCapture()函数,能用来定义“摄像头”对象,0表示第一个摄像头(一般是电脑内置的摄像头);如果有两个摄像头,第二个摄像头则对应VideoCapture(1)。
在while循环中使用“摄像头对象”的read()函数一帧一帧地读取摄像头画面数据。
imshow函数是显示摄像头的某帧画面;cv2.waitKey(1)是等待1ms,如果期间检测到了键盘输入q,则退出while循环。
效果
2)分辨率2560x720
源代码:
# -*- coding: utf-8 -*- import cv2 import time AUTO = False # 自动拍照,或手动按s键拍照 INTERVAL = 2 # 自动拍照间隔 cv2.namedWindow("left") cv2.namedWindow("right") camera = cv2.VideoCapture(0) # 设置分辨率左右摄像机同一频率,同一设备ID;左右摄像机总分辨率2560x720;分割为两个1280x720 camera.set(cv2.CAP_PROP_FRAME_WIDTH,2560) camera.set(cv2.CAP_PROP_FRAME_HEIGHT,720) counter = 0 utc = time.time() folder = "./SaveImage/" # 拍照文件目录 def shot(pos, frame): global counter path = folder + pos + "_" + str(counter) + ".jpg" cv2.imwrite(path, frame) print("snapshot saved into: " + path) while True: ret, frame = camera.read() print("ret:",ret) # 裁剪坐标为[y0:y1, x0:x1] HEIGHT * WIDTH left_frame = frame[0:720, 0:1280] right_frame = frame[0:720, 1280:2560] cv2.imshow("left", left_frame) cv2.imshow("right", right_frame) now = time.time() if AUTO and now - utc >= INTERVAL: shot("left", left_frame) shot("right", right_frame) counter += 1 utc = now key = cv2.waitKey(1) if key == ord("q"): break elif key == ord("s"): shot("left", left_frame) shot("right", right_frame) counter += 1 camera.release() cv2.destroyWindow("left") cv2.destroyWindow("right")
其他版本:OpenCV 双目摄像头拍照 C++