python opencv 获取fps 帧率

使用OpenCV获取摄像头帧率与性能分析

最新推荐文章于 2025-03-17 10:00:00 发布

原创最新推荐文章于 2025-03-17 10:00:00 发布 · 8.9k 阅读

6 ·

CC 4.0 BY-SA版权

文章标签：

#opencv #人工智能 #计算机视觉

python 专栏收录该内容

2 篇文章

订阅专栏

该博客介绍了如何使用OpenCV库在Python中打开默认摄像头，并通过两种方式获取帧率：直接使用`cv2.CAP_PROP_FPS`属性（在某些情况下可能返回异常值）以及通过计时器计算实际帧率。博主还展示了如何计算在指定帧数下捕获视频所用的时间，从而估算出实际的帧率。

#!/usr/bin/env python

import cv2
import time

if __name__ == '__main__' :

    # Start default camera
    video = cv2.VideoCapture(0);

    # Find OpenCV version
    (major_ver, minor_ver, subminor_ver) = (cv2.__version__).split('.')

    # With webcam get(CV_CAP_PROP_FPS) does not work.
    # Let's see for ourselves.

    if int(major_ver)  < 3 :
        fps = video.get(cv2.cv.CV_CAP_PROP_FPS)
        print("Frames per second using video.get(cv2.cv.CV_CAP_PROP_FPS): {0}".format(fps))
    else :
        fps = video.get(cv2.CAP_PROP_FPS)
        print("Frames per second using video.get(cv2.CAP_PROP_FPS) : {0}".format(fps))

    # Number of frames to capture
    num_frames = 120;

    print("Capturing {0} frames".format(num_frames))

    # Start time
    start = time.time()

    # Grab a few frames
    for i in range(0, num_frames) :
        ret, frame = video.read()

    # End time
    end = time.time()

    # Time elapsed
    seconds = end - start
    print ("Time taken : {0} seconds".format(seconds))

    # Calculate frames per second
    fps  = num_frames / seconds
    print("Estimated frames per second : {0}".format(fps))

    # Release video
    video.release()

注意

cap.get(cv2.CAP_PROP_FPS) 有时会获取到异常值 180000.0,所以当异常时使用时间差的方式获取