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### There is something wrong when I read 2+ cameras.

I have a project recently that I need to read more than 2 cameras using OpenCV. But I am facing a weird problem that I can't solve. When I execute my code step by step, it just OK, but when I run my project automatically, there is something wrong. Here is my code:

while (1)
{
////////////////////////////////////////////////////////////////////////////////
//When I execute the following part step by step, it is just OK
//But when I run the project automatically, there is someting wrong
for (i=0; i<3; i++){
cap = cvCaptureFromCAM(i);
cvGrabFrame(cap);
cam = cvRetrieveFrame(cap);
cvCopy(cam, ImageBuffer[i]);
cvReleaseCapture(&cap);
}
///////////////////////////////////////////////////////////////////////////////
cvGetCols(pairs, &part, 0, 640);
cvCopy(ImageBuffer[0], &part);
cvGetCols(pairs, &part, 640, 640*2);
cvCopy(ImageBuffer[1], &part);
cvGetCols(pairs, &part, 640*2, 640*3);
cvCopy(ImageBuffer[2], &part);
cvShowImage("Pairs", pairs);

if(27==cvWaitKey(10))
break;
}


When I run the project, the error is like that:

So, what is wrong with my code? Can anyone could solve the problem? Thanks In Advance!

 2 retagged sturkmen 6772 ●3 ●48 ●79 https://github.com/stu...

### There is something wrong when I read 2+ cameras.

I have a project recently that I need to read more than 2 cameras using OpenCV. But I am facing a weird problem that I can't solve. When I execute my code step by step, it just OK, but when I run my project automatically, there is something wrong. Here is my code:

while (1)
{
////////////////////////////////////////////////////////////////////////////////
//When I execute the following part step by step, it is just OK
//But when I run the project automatically, there is someting wrong
for (i=0; i<3; i++){
cap = cvCaptureFromCAM(i);
cvGrabFrame(cap);
cam = cvRetrieveFrame(cap);
cvCopy(cam, ImageBuffer[i]);
cvReleaseCapture(&cap);
}
///////////////////////////////////////////////////////////////////////////////
cvGetCols(pairs, &part, 0, 640);
cvCopy(ImageBuffer[0], &part);
cvGetCols(pairs, &part, 640, 640*2);
cvCopy(ImageBuffer[1], &part);
cvGetCols(pairs, &part, 640*2, 640*3);
cvCopy(ImageBuffer[2], &part);
cvShowImage("Pairs", pairs);

if(27==cvWaitKey(10))
break;
}


When I run the project, the error is like that:

So, what is wrong with my code? Can anyone could solve the problem? Thanks In Advance!