Qt: Capturing images from camera continuously fills the whole memory
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I am trying to capture images continuously so I can send them using UDP. I am doing this to implement a live video streaming program.
The code below captures images continuously and assigns images to QGraphicsScene so I can test if images play like a video. But when I run the program my computer freezes even though I delete the pointers. How can I optimize this code ?
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QThread>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
scene = new QGraphicsScene(this);
ui->graphicsView->setScene(scene);
cam = new QCamera;
cam->setCaptureMode(QCamera::CaptureStillImage);
viewfinder = new QCameraViewfinder;
viewfinder->show();
QCameraImageCapture *cap = new QCameraImageCapture(cam);
cap->setCaptureDestination(QCameraImageCapture::CaptureToBuffer);
cam->setViewfinder(viewfinder);
QObject::connect(cap, &QCameraImageCapture::imageCaptured, [=] (int id, QImage img) {
while(true){
QByteArray *buf = new QByteArray;
QBuffer *buffer=new QBuffer(buf);
buffer->open(QIODevice::WriteOnly);
img.save(buffer, "BMP");
QPixmap *pixmap = new QPixmap();
pixmap->loadFromData(buffer->buffer());
scene->addPixmap(*pixmap);
delete buf;
delete buffer;
delete pixmap;
QThread::sleep(0.0416);
cap->capture();
}
});
QObject::connect(cap, &QCameraImageCapture::readyForCaptureChanged, [=] (bool state) {
if(state == true) {
cam->searchAndLock();
cap->capture();
cam->unlock();
}
});
cam->start();
}
MainWindow::~MainWindow()
{
delete ui;
}
c++ memory-management memory-optimization qt
asked 23 mins ago
onur cevik
42
add a comment |
up vote
-1
down vote
favorite
I am trying to capture images continuously so I can send them using UDP. I am doing this to implement a live video streaming program.
The code below captures images continuously and assigns images to QGraphicsScene so I can test if images play like a video. But when I run the program my computer freezes even though I delete the pointers. How can I optimize this code ?
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QThread>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
scene = new QGraphicsScene(this);
ui->graphicsView->setScene(scene);
cam = new QCamera;
cam->setCaptureMode(QCamera::CaptureStillImage);
viewfinder = new QCameraViewfinder;
viewfinder->show();
QCameraImageCapture *cap = new QCameraImageCapture(cam);
cap->setCaptureDestination(QCameraImageCapture::CaptureToBuffer);
cam->setViewfinder(viewfinder);
QObject::connect(cap, &QCameraImageCapture::imageCaptured, [=] (int id, QImage img) {
while(true){
QByteArray *buf = new QByteArray;
QBuffer *buffer=new QBuffer(buf);
buffer->open(QIODevice::WriteOnly);
img.save(buffer, "BMP");
QPixmap *pixmap = new QPixmap();
pixmap->loadFromData(buffer->buffer());
scene->addPixmap(*pixmap);
delete buf;
delete buffer;
delete pixmap;
QThread::sleep(0.0416);
cap->capture();
}
});
QObject::connect(cap, &QCameraImageCapture::readyForCaptureChanged, [=] (bool state) {
if(state == true) {
cam->searchAndLock();
cap->capture();
cam->unlock();
}
});
cam->start();
}
MainWindow::~MainWindow()
{
delete ui;
}
c++ memory-management memory-optimization qt
asked 23 mins ago
onur cevik
42
add a comment |
up vote
-1
down vote
favorite
up vote
-1
down vote
favorite
I am trying to capture images continuously so I can send them using UDP. I am doing this to implement a live video streaming program.
The code below captures images continuously and assigns images to QGraphicsScene so I can test if images play like a video. But when I run the program my computer freezes even though I delete the pointers. How can I optimize this code ?
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QThread>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
scene = new QGraphicsScene(this);
ui->graphicsView->setScene(scene);
cam = new QCamera;
cam->setCaptureMode(QCamera::CaptureStillImage);
viewfinder = new QCameraViewfinder;
viewfinder->show();
QCameraImageCapture *cap = new QCameraImageCapture(cam);
cap->setCaptureDestination(QCameraImageCapture::CaptureToBuffer);
cam->setViewfinder(viewfinder);
QObject::connect(cap, &QCameraImageCapture::imageCaptured, [=] (int id, QImage img) {
while(true){
QByteArray *buf = new QByteArray;
QBuffer *buffer=new QBuffer(buf);
buffer->open(QIODevice::WriteOnly);
img.save(buffer, "BMP");
QPixmap *pixmap = new QPixmap();
pixmap->loadFromData(buffer->buffer());
scene->addPixmap(*pixmap);
delete buf;
delete buffer;
delete pixmap;
QThread::sleep(0.0416);
cap->capture();
}
});
QObject::connect(cap, &QCameraImageCapture::readyForCaptureChanged, [=] (bool state) {
if(state == true) {
cam->searchAndLock();
cap->capture();
cam->unlock();
}
});
cam->start();
}
MainWindow::~MainWindow()
{
delete ui;
}
c++ memory-management memory-optimization qt
asked 23 mins ago
onur cevik
42
I am trying to capture images continuously so I can send them using UDP. I am doing this to implement a live video streaming program.
The code below captures images continuously and assigns images to QGraphicsScene so I can test if images play like a video. But when I run the program my computer freezes even though I delete the pointers. How can I optimize this code ?
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QThread>
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
scene = new QGraphicsScene(this);
ui->graphicsView->setScene(scene);
cam = new QCamera;
cam->setCaptureMode(QCamera::CaptureStillImage);
viewfinder = new QCameraViewfinder;
viewfinder->show();
QCameraImageCapture *cap = new QCameraImageCapture(cam);
cap->setCaptureDestination(QCameraImageCapture::CaptureToBuffer);
cam->setViewfinder(viewfinder);
QObject::connect(cap, &QCameraImageCapture::imageCaptured, [=] (int id, QImage img) {
while(true){
QByteArray *buf = new QByteArray;
QBuffer *buffer=new QBuffer(buf);
buffer->open(QIODevice::WriteOnly);
img.save(buffer, "BMP");
QPixmap *pixmap = new QPixmap();
pixmap->loadFromData(buffer->buffer());
scene->addPixmap(*pixmap);
delete buf;
delete buffer;
delete pixmap;
QThread::sleep(0.0416);
cap->capture();
}
});
QObject::connect(cap, &QCameraImageCapture::readyForCaptureChanged, [=] (bool state) {
if(state == true) {
cam->searchAndLock();
cap->capture();
cam->unlock();
}
});
cam->start();
}
MainWindow::~MainWindow()
{
delete ui;
}
c++ memory-management memory-optimization qt
c++ memory-management memory-optimization qt
asked 23 mins ago
onur cevik
42
asked 23 mins ago
onur cevik
42
asked 23 mins ago
onur cevik
42
asked 23 mins ago
onur cevik
42
asked 23 mins ago
onur cevik
42
42
add a comment |
add a comment |
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