Increase fps on Basler camera - c++

Question

I am working in a real time image processing project, I am using a Basler camera model acA1300-200uc with communication by USB3, but I am having troubles with the fps of my c++ program because the camera supports over 200 fps but my program only runs arround 30 fps and I dont know how to increase it, my project need 100 fps aprox.
This is my code, I hope you can help me, thanks in advance.
#include <Windows.h>
#include <opencv2\core\core.hpp>
#include <opencv2\highgui\highgui.hpp>
#include <opencv2\video\video.hpp>
#include <pylon\PylonIncludes.h>
#include <time.h>
using namespace Pylon;
// Settings for using Basler USB cameras.
#include <pylon/usb/BaslerUsbInstantCamera.h>
typedef Pylon::CBaslerUsbInstantCamera Camera_t;
using namespace Basler_UsbCameraParams;
using namespace cv;
using namespace std;
static const uint32_t c_countOfImagesToGrab = 1000;
int main(int argc, char* argv[]) {
int frames = 0;
double seconds = 0,fps;
time_t start, end;
Pylon::PylonAutoInitTerm autoInitTerm;
try
{
CDeviceInfo info;
info.SetDeviceClass(Camera_t::DeviceClass());
Camera_t camera(CTlFactory::GetInstance().CreateFirstDevice(info));
cout << "Dispositivo utilizado: " << camera.GetDeviceInfo().GetModelName() << endl;
camera.Open();
camera.MaxNumBuffer = 10;
CImageFormatConverter formatConverter;
formatConverter.OutputPixelFormat = PixelType_BGR8packed;
CPylonImage pylonImage;
Mat openCvImage, gray_img;
vector<Vec3f> circles;
int64_t W = 800, H = 600;
camera.Width.SetValue(W);
camera.Height.SetValue(H);
camera.StartGrabbing(c_countOfImagesToGrab, GrabStrategy_LatestImageOnly);
CGrabResultPtr ptrGrabResult;
camera.RetrieveResult(5000, ptrGrabResult, TimeoutHandling_ThrowException);
cout << "SizeX: " << ptrGrabResult->GetWidth() << endl;
cout << "SizeY: " << ptrGrabResult->GetHeight() << endl;
cvNamedWindow("OpenCV Display Window", CV_WINDOW_AUTOSIZE);
time(&start);
while (camera.IsGrabbing())
{
camera.RetrieveResult(5000, ptrGrabResult, TimeoutHandling_ThrowException);
if (ptrGrabResult->GrabSucceeded())
{
formatConverter.Convert(pylonImage, ptrGrabResult);
openCvImage = Mat(ptrGrabResult->GetHeight(), ptrGrabResult->GetWidth(), CV_8UC3, (uint8_t *)pylonImage.GetBuffer());
imshow("OpenCV Display Window", openCvImage);
frames++;
if (waitKey(30)>=0) break;
}
}
time(&end);
}
catch (...) { cout << "error" << endl; }
seconds = difftime(end, start);
fps = frames / seconds;
cout << "fps: " << fps;
Sleep(1000);
}

Answer 1

Frame rate is affected by many parameters. If the manufacturer specifies 200fps as the maximum at full resolution, this is the absolute maximum with:
minimum exposure time (too small for most applications)
nothing else going on on the USB bus
optimal transfer and acquisition parameters (maximum aquisition frame rate, no bandwidth limitations, fast readout mode
...
In case you haven't noticed, that's the marketing guy with big and juicy bait. 200fps cannot be achieved in most applications due to many factors.
You can read out the resulting framerate for your current configuration like that:
// Get the resulting frame rate
double d = camera.ResultingFrameRate.GetValue();
Refer to the camera's user manual... There's an entire chapter on frame rate, framerate limitations, framerate optimization
I also see a waitkey(30) call in your fps measurement. This function will delay your grab loop for at least 30ms unless you press any key. If you display each frame for 30 milliseconds (at least that's how I understand the waitkey documentation), how are you supposed to reach 100 fps? 1 frame / 0.03 s = 33.33 fps.