QT frame visualisation - c++

Question

Currently started to work with qt and found some bug in my code, and I can't understand where it comes from. Maybe you will see and explain why it happens.
Here is main.cpp code part which changes shutter from 3000 to maximum:
if (camera.test_cam->liveFrameReady())
{
camera.visualizeFrame(camera.test_cam->liveFrame());
camera.set_shutter(0, 1, 3000 + i * 200);
controlWidget->update(camera.test_cam->liveFrame());
i++;
}
The code works slowly(1 fps ), because of the camera.visuzlizeFrame() method:
void OsCam::visualizeFrame(Common::FrameHandle hFrame)
{
void* buffer_ptr = this->getFrameData(hFrame);
int width = hFrame->dataType()->width();
int height = hFrame->dataType()->height();
cv::Mat m(height, width, CV_8UC3, (int*)buffer_ptr);
cv::imshow("test image", m);
cv::waitKey(1);
}
Gui interface shows the camera frame in real time, test image from visualizeFrame at the background
Actionally, I don't need to call this method (I used it just to be sure that I can read the memory and I used opencv because I am more familiar with it).
But if I get rid of this camera.visuzlizeFrame() my gui becomes white and does not give any response.
Even if I use cv::waitKey or Sleep functions, nothing happens to the gui.
void ControlWidget::update(Common::FrameHandle hFrame)
{
try
{
QImage img((uchar*)hFrame->buffer()->data(), hFrame->dataType()->width(), hFrame->dataType()->height(), QImage::Format::Format_RGB888);
QSize standart_size = QSize(hFrame->dataType()->width() / 3, hFrame->dataType()->height() / 3);
QPixmap rectPxmp = QPixmap::fromImage(img).scaled(standart_size);
this->camera_1->setPixmap(rectPxmp);
this->camera_2->setPixmap(rectPxmp);
cv::waitKey(300);
}
catch (GeneralException& e)
{
std::cout << e.what() << std::endl;
}
}
Shall I go to QThreads? One thread for reading the buffer and another one for visualization of gui?
Thank you!
some additional code:
void* OsCam::getFrameData(Common::FrameHandle hFrame)
{
bool displayFrameData = false;
void* pFrameData = NULL;
try
{
if (hFrame)
{
if (displayFrameData)
{
// display information about the frame
cout << "Frame index: " << hFrame->frameIndex();
cout << "Frame timestamp: " << hFrame->timestamp();
// display information about the frame "data type"
DataTypeHandle hDataType = hFrame->dataType();
cout << "Frame size in bytes: " << hDataType->frameSizeInBytes() << endl;
cout << "Width in pixels: " << DataType::width(hDataType) << endl;
cout << "Height in rows: " << DataType::height(hDataType) << endl;
cout << "Bit depth: " << DataType::bitDepth(hDataType) << endl;
cout << "Bytes/line (stride): " << DataType::stride(hDataType) << endl;
// display the frame video format
VideoDataType::Format videoFormat = VideoDataType::format(hDataType);
cout << "Video format: " << VideoDataType::formatString(videoFormat).c_str() << endl;
// get a pointer to the frame data
}
pFrameData = hFrame->buffer()->data();
}
}
catch (GeneralException& e)
{
cout << e.what() << endl;
}
return pFrameData;
}
and main (I changed it a little bit) :
int main(int argc, char **argv)
{
QApplication app(argc, argv);
ControlWidget *controlWidget = new ControlWidget;
//controlWidget->show();
try
{
OsCam camera;
int i = 0;
for (int j = 0; j<10000 ; j++)
{
if ((camera.test_cam->liveFrameReady()))
{
Common::FrameHandle loaded = camera.test_cam->liveFrame()->clone();
camera.visualizeFrame(loaded);
controlWidget->update(loaded);
camera.set_shutter(0, 1, 3000 + i * 200);
loaded->~Frame();
}
i++;
}
}
catch (GeneralException& e)
{
std::cout << e.what() << std::endl;
int a;
std::cin >> a;
return 1;
}
}
After cv::named_window