OpenCV2之简单处理视频

OpenCV2
https://www.geeksforgeeks.org/opencv-python-tutorial/

• 视频采集

    import cv2

    currentframe = 0
    cap = cv2.VideoCapture(0)
    while cap.isOpened():
        ret, frame = cap.read()
        cv2.imshow('frame', frame)

        # 隔多少帧保存一张图片
        if currentframe % 10 == 0:
            cv2.imwrite(f'{TEMP_PATH}/cap/{int(time.time() * 1000)}.png', frame)
        currentframe += 1

        # 退出
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break

    cap.release()
    cv2.destroyAllWindows()

• 视频处理（处理帧+加文字）

    import cv2

    currentframe = 0
    cap = cv2.VideoCapture(0)
    while cap.isOpened():
        ret, frame = cap.read()

        frame = cv2.rectangle(frame, (frame.size, frame.size), (frame.size - 80, frame.size - 30), (246, 64, 65), 1)

        cv2.putText(frame,
                    'this is a demo test',
                    (50, 50),
                    cv2.FONT_HERSHEY_PLAIN, 1,
                    (0, 255, 255),
                    2,
                    cv2.LINE_4)
        cv2.imshow('frame', frame)

        # 隔多少帧保存一张图片
        if currentframe % 101 == 0:
            cv2.imwrite(f'{TEMP_PATH}/cap/{int(time.time() * 1000)}.png', frame)
        currentframe += 1

        # 退出
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break

    cap.release()
    cv2.destroyAllWindows()