Question

设备：
1.树莓派2 2. Raspberry Pi相机

软件：
1. OpenCV 2.4.11
2.使用C ++编程

我有以下简单的代码从相机捕获视频并在窗口中显示它帧大小始终为640 x 480，尝试更改帧宽和高度（如标注行中所示）没有帮助，它保持640 x 480。

我正在寻找一种方法将帧宽和高度从我的代码更改为1920 x 1080（而不是使用shell）。
如果可以从OpenCV或V4l2驱动程序完成它将是伟大的

#include "opencv2/highgui/highgui.hpp"
#include <iostream>

using namespace cv;
using namespace std;

int main(int argc, char* argv[]) {

    int rc = 0 ;
    int device = 0 ;

    Mat frame;

    namedWindow( "Video", CV_WINDOW_AUTOSIZE ) ;

    VideoCapture capture( device ) ;
    if( capture.isOpened()) {

        cout << "Frame size : " << capture.get(CV_CAP_PROP_FRAME_WIDTH) << " x " << capture.get(CV_CAP_PROP_FRAME_HEIGHT) << endl ;

        //capture.set( CV_CAP_PROP_FRAME_WIDTH, 1920 ) ;
        //capture.set( CV_CAP_PROP_FRAME_HEIGHT, 1080 ) ;
        //capture.set( CV_CAP_PROP_FOURCC, CV_PROP('H','2','6','4')) ;
        //capture.set( CV_CAP_PROP_FOURCC, CV_PROP('M','J','P','G')) ;
        //capture.set( CV_CAP_PROP_FPS, 10 );

        for( ; ; ) {

            if( capture.read( frame )) {

                imshow( "Video", frame );

                if( waitKey( 1 ) == 27 ) {
                    cout << "Esc key pressed by the user" << endl ;
                    break ;
                }
            }
            else {
                rc = -1 ;
                cout << "Cannot read frame from video stream" << endl ;
                break ;
            }
        }
    }
    else {
        rc = -1 ;
        cout << "Cannot open the video device " << device << endl ;
    }

    return( rc ) ;
}

Answer 1

看看Raspicam项目。它可以帮助调整RPI上的摄像头分辨率并与OpenCV很好地集成。 https://github.com/cedricve/raspicam

编辑：在这里附上我的测试代码。它在RPI B2上对我很好。曝光值介于1到100000之间。

#include <ctime>
#include <iostream>
#include <raspicam/raspicam_cv.h> 
using namespace std; 

int main ( int argc,char **argv ) {

    time_t timer_begin,timer_end;
    raspicam::RaspiCam_Cv Camera;
    Camera.set(CV_CAP_PROP_EXPOSURE, 100);
    cv::Mat image;
    int nCount=10;
    //set camera params
    Camera.set( CV_CAP_PROP_FORMAT, CV_8UC1 );
    //Open camera
    cout<<"Opening Camera..."<<endl;
    if (!Camera.open()) {cerr<<"Error opening the camera"<<endl;return -1;}
    //Start capture
    cout<<"Capturing "<<nCount<<" frames ...."<<endl;
    time ( &timer_begin );
    for ( int i=0; i<nCount; i++ ) {
        Camera.grab();
        Camera.retrieve ( image);
        if ( i%5==0 )  cout<<"\r captured "<<i<<" images"<<std::flush;
    }
    cout<<"Stop camera..."<<endl;
    Camera.release();
    //show time statistics
    time ( &timer_end ); /* get current time; same as: timer = time(NULL)  */
    double secondsElapsed = difftime ( timer_end,timer_begin );
    cout<< secondsElapsed<<" seconds for "<< nCount<<"  frames : FPS = "<<  ( float ) ( ( float ) ( nCount ) /secondsElapsed ) <<endl;
    //save image 
    cv::imwrite("raspicam_cv_image_100.jpg",image);
    cout<<"Image saved at raspicam_cv_image_100.jpg"<<endl;
}

通过Raspberry PI在OpenCV上捕获1920x1080视频

1 个答案: