How can I capture frames from IP cameras with OpenCV?

Capturing Frames from IP Cameras with OpenCV

To capture frames from an IP camera using OpenCV, you can employ the following steps:

1. Include the Necessary Libraries:

   • For OpenCV version 2.0 or higher:

     • #include "cv.h"
     • #include "highgui.h"

   • For older versions of OpenCV (e.g., 1.1pre1):

     • #include "cv.h"
     • #include "highgui.h"

2. Open the Video Stream:

   • Use cv::VideoCapture to open the video stream. For example:

     • cv::VideoCapture vcap("rtsp://cam_address:554/live.sdp"); // RTSP stream
     • cv::VideoCapture vcap("http://user:pass@cam_address:8081/cgi/mjpg/mjpg.cgi?.mjpg"); // MJPEG stream

3. Read Frames:

   • Use vcap.read(image) to read frames into a cv::Mat image.

4. Display Frames:

   • Create an output window using cv::namedWindow("Output Window").
   • Display frames using cv::imshow("Output Window", image).

5. Handle User Interaction:

   • Use cv::waitKey() to wait for user input or a specified time interval.

Example Code for OpenCV 2.0 :

#include "cv.h"
#include "highgui.h"
#include <iostream>

int main(int, char**) {
    cv::VideoCapture vcap;
    cv::Mat image;

    const std::string videoStreamAddress = "rtsp://cam_address:554/live.sdp";  // RTSP stream

    // Open the video stream and check if it's open
    if (!vcap.open(videoStreamAddress)) {
        std::cout << "Error opening video stream or file" << std::endl;
        return -1;
    }

    // Create output window for displaying frames.
    cv::namedWindow("Output Window");

    for (;;) {
        if (!vcap.read(image)) {
            std::cout << "No frame" << std::endl;
            cv::waitKey();
        }
        cv::imshow("Output Window", image);
        if (cv::waitKey(1) >= 0) break;
    }

    return 0;
}

Update for H.264 RTSP Streams:

To capture frames from H.264 RTSP streams with OpenCV 2.0 or higher, you can use the following URL format:

• rtsp://10.10.10.10:554/axis-media/media.amp

If the camera requires authentication, use the following URL format:

• rtsp://username:[email protected]:554/axis-media/media.amp

The above is the detailed content of How can I capture frames from IP cameras with OpenCV?. For more information, please follow other related articles on the PHP Chinese website!