Question

有人知道如何使用视频编写器吗？我有一个简单的脚本，可以使用笔记本电脑网络摄像头通过haar_cascades检测面部，我试图弄清楚如何将检测到的面部周围的框写入输出到视频文件中。用于haar级联的.xml文件保存到目录中，并且程序以循环格式运行。我在下面评论的是#cv2.VideoWriter.write(frame)，它不起作用，因为视频编写器不希望使用numpy数组。

import numpy as np
import cv2, time
import matplotlib.pyplot as plt

haar_face_cascade = cv2.CascadeClassifier('opencv-master/opencv-master/data/haarcascades/haarcascade_frontalface_alt.xml')
video = cv2.VideoCapture(0)  
a = 0


while True:

    a = a + 1    
    check, frame = video.read()

    print(check)
    print(frame)

    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    faces = haar_face_cascade.detectMultiScale(gray, scaleFactor=1.1, minNeighbors=5);
    for (x, y, w, h) in faces:
        cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 0, 255), 2)


    cv2.imshow("Face Detector", frame)
    #cv2.VideoWriter.write(frame)


    if cv2.waitKey(1) & 0xFF == ord("q"):
        break

print(a)

video.release()
cv2.destroyAllWindows()

Answer 1

所以我做了一些研究并弄清楚了... https://docs.opencv.org/3.1.0/dd/d43/tutorial_py_video_display.html

import numpy as np
import cv2


haar_face_cascade = cv2.CascadeClassifier('haarcascades/haarcascade_frontalface_alt.xml')
video = cv2.VideoCapture(0)  
a = 0

fourcc = cv2.VideoWriter_fourcc(*'XVID')
out = cv2.VideoWriter('output.avi',fourcc, 20.0, (640,480))

while True:


    a = a + 1    
    check, frame = video.read()


    print(frame)

    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
    faces = haar_face_cascade.detectMultiScale(gray, scaleFactor=1.1, minNeighbors=5);
    for (x, y, w, h) in faces:
        cv2.rectangle(frame, (x, y), (x+w, y+h), (0, 0, 255), 2)

    out.write(frame)
    cv2.imshow("Face Detector", frame)


    key = cv2.waitKey(1)    
    if key == ord('q'):
        break

print(a)

video.release()
out.release()
cv2.destroyAllWindows()

Python OpenCV视频编写器

1 个答案: