How can I capture the cameras' video at the real time?

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camera

C++14

I'm using Usb 3.0 Basler camera acA640-750uc to capture the video and here is the program to use 2 cameras and grab the frame:

#include <pylon/PylonIncludes.h>
#ifdef PYLON_WIN_BUILD
#    include <pylon/PylonGUI.h>
#endif

// Namespace for using pylon objects.
using namespace Pylon;

// Namespace for using cout.
using namespace std;

// Number of images to be grabbed.
static const uint32_t c_countOfImagesToGrab = 1000;

// Limits the amount of cameras used for grabbing.
// It is important to manage the available bandwidth when grabbing with multiple cameras.
// This applies, for instance, if two GigE cameras are connected to the same network adapter via a switch.
// To manage the bandwidth, the GevSCPD interpacket delay parameter and the GevSCFTD transmission delay
// parameter can be set for each GigE camera device.
// The "Controlling Packet Transmission Timing with the Interpacket and Frame Transmission Delays on Basler GigE Vision Cameras"
// Application Notes (AW000649xx000)
// provide more information about this topic.
// The bandwidth used by a FireWire camera device can be limited by adjusting the packet size.
static const size_t c_maxCamerasToUse = 2;

int main(int argc, char* argv[])
{
	// The exit code of the sample application.
	int exitCode = 0;

	// Before using any pylon methods, the pylon runtime must be initialized. 
	PylonInitialize();

	try
	{
		// Get the transport layer factory.
		CTlFactory& tlFactory = CTlFactory::GetInstance();

		// Get all attached devices and exit application if no device is found.
		DeviceInfoList_t devices;
		if (tlFactory.EnumerateDevices(devices) == 0)
		{
			throw RUNTIME_EXCEPTION("No camera present.");
		}

		// Create an array of instant cameras for the found devices and avoid exceeding a maximum number of devices.
		CInstantCameraArray cameras(min(devices.size(), c_maxCamerasToUse));

		// Create and attach all Pylon Devices.
		for (size_t i = 0; i < cameras.GetSize(); ++i)
		{
			cameras[i].Attach(tlFactory.CreateDevice(devices[i]));

			// Print the model name of the camera.
			cout << "Using device " << cameras[i].GetDeviceInfo().GetModelName() << endl;
		}

		// Starts grabbing for all cameras starting with index 0. The grabbing
		// is started for one camera after the other. That's why the images of all
		// cameras are not taken at the same time.
		// However, a hardware trigger setup can be used to cause all cameras to grab images synchronously.
		// According to their default configuration, the cameras are
		// set up for free-running continuous acquisition.
		cameras.StartGrabbing();

		// This smart pointer will receive the grab result data.
		CGrabResultPtr ptrGrabResult;

		// Grab c_countOfImagesToGrab from the cameras.
		for (uint32_t i = 0; i < c_countOfImagesToGrab && cameras.IsGrabbing(); ++i)
		{
			cameras.RetrieveResult(5000, ptrGrabResult, TimeoutHandling_ThrowException);

			// When the cameras in the array are created the camera context value
			// is set to the index of the camera in the array.
			// The camera context is a user settable value.
			// This value is attached to each grab result and can be used
			// to determine the camera that produced the grab result.
			intptr_t cameraContextValue = ptrGrabResult->GetCameraContext();

#ifdef PYLON_WIN_BUILD
			// Show the image acquired by each camera in the window related to each camera.
			Pylon::DisplayImage(cameraContextValue, ptrGrabResult);
#endif

			// Print the index and the model name of the camera.
			cout << "Camera " << cameraContextValue << ": " << cameras[cameraContextValue].GetDeviceInfo().GetModelName() << endl;

			// Now, the image data can be processed.
			cout << "GrabSucceeded: " << ptrGrabResult->GrabSucceeded() << endl;
			cout << "SizeX: " << ptrGrabResult->GetWidth() << endl;
			cout << "SizeY: " << ptrGrabResult->GetHeight() << endl;
			const uint8_t* pImageBuffer = (uint8_t*)ptrGrabResult->GetBuffer();
			cout << "Gray value of first pixel: " << (uint32_t)pImageBuffer[0] << endl << endl;
		}
	}
	catch (const GenericException& e)
	{
		// Error handling
		cerr << "An exception occurred." << endl
			<< e.GetDescription() << endl;
		exitCode = 1;
	}

	// Comment the following two lines to disable waiting on exit.
	cerr << endl << "Press Enter to exit." << endl;
	while (cin.get() != '\n');

	// Releases all pylon resources. 
	PylonTerminate();

	return exitCode;
}

The problem is when i run this program the camera start to capture the video but the video is about 2 seconds slower than my exact movement in real time
How can i fix this?
Thank you

What I have tried:

First i've added this program to video capture program i've written before to see if it changed but it didn't.