opencv将webcam输出写入avi文件
我正尝试使用opencv从我的摄像头输出创建一个avi视频。 不会抛出任何异常，但是它创建的avi文件大小为414字节，不会增长。
它也不会与任何媒体播放器一起玩。 我怀疑写入文件部分有问题。
代码如下：
CvCapture *capture = cvCaptureFromCAM( 0 );
int width = ( int )cvGetCaptureProperty( capture,
CV_CAP_PROP_FRAME_WIDTH );
int height = ( int )cvGetCaptureProperty( capture,
CV_CAP_PROP_FRAME_HEIGHT );
CvVideoWriter *writer = cvCreateVideoWriter("CamCapture.avi",
-1,30, cvSize( width, height ) );
cvNamedWindow("capWindow", CV_WINDOW_AUTOSIZE);
IplImage *frame = 0;
// this returns 0 not sure why ??
//double fps = cvGetCaptureProperty(capture, CV_CAP_PROP_FPS);
double fps = 30;
while( 1 )
{
frame = cvQueryFrame( capture );
cvShowImage("capWindow",frame);
cvWriteFrame( writer, frame );
char c = cvWaitKey(1000/fps);
if( c == 27 ) break;
}
cvReleaseCapture( &capture );
cvReleaseVideoWriter( &writer );
cvDestroyWindow( "capWindow" );
我已经参考并尝试了以下样品，但没有运气：
不要使用过时的c，使用c ++ api，它很容易使用和简单，例如上面的代码可以在c ++中重写，
#include "opencv2/opencv.hpp"
#include <iostream>
using namespace std;
using namespace cv;
int main(){
VideoCapture vcap(0);
if(!vcap.isOpened()){
cout << "Error opening video stream or file" << endl;
return -1;
}
int frame_width= vcap.get(CV_CAP_PROP_FRAME_WIDTH);
int frame_height= vcap.get(CV_CAP_PROP_FRAME_HEIGHT);
VideoWriter video("out.avi",CV_FOURCC('M','J','P','G'),10, Size(frame_width,frame_height),true);
for(;;){
Mat frame;
vcap >> frame;
video.write(frame);
imshow( "Frame", frame );
char c = (char)waitKey(33);
if( c == 27 ) break;
}
return 0;
}
使用下面的代码从捕捉相机输入中编写AVI格式。
#include "opencv2/highgui/highgui.hpp"
#include <iostream>
using namespace cv;
using namespace std;
int main(int argc, char* argv[])
{
VideoCapture cap(0); // open the video camera no. 0
if (!cap.isOpened()) // if not success, exit program
{
cout << "ERROR: Cannot open the video file" << endl;
return -1;
}
namedWindow("MyVideo",CV_WINDOW_AUTOSIZE); //create a window called "MyVideo"
double dWidth = cap.get(CV_CAP_PROP_FRAME_WIDTH); //get the width of frames of the video
double dHeight = cap.get(CV_CAP_PROP_FRAME_HEIGHT); //get the height of frames of the video
cout << "Frame Size = " << dWidth << "x" << dHeight << endl;
Size frameSize(static_cast<int>(dWidth), static_cast<int>(dHeight));
VideoWriter oVideoWriter ("D:/MyVideo.avi", CV_FOURCC('P','I','M','1'), 20, frameSize, true); //initialize the VideoWriter object
if ( !oVideoWriter.isOpened() ) //if not initialize the VideoWriter successfully, exit the program
{
cout << "ERROR: Failed to write the video" << endl;
return -1;
}
while (1)
{
Mat frame;
bool bSuccess = cap.read(frame); // read a new frame from video
if (!bSuccess) //if not success, break loop
{
cout << "ERROR: Cannot read a frame from video file" << endl;
break;
}
oVideoWriter.write(frame); //writer the frame into the file
imshow("MyVideo", frame); //show the frame in "MyVideo" window
if (waitKey(10) == 27) //wait for 'esc' key press for 30ms. If 'esc' key is pressed, break loop
{
cout << "esc key is pressed by user" << endl;
break;
}
}
return 0;
}