editing a image using QT

[qtlearner123]

Hi all,

i have this doubt if i have an image in my computer and i access that image (.jpeg or anyother format) using QT program and after accessing the image is it possible for me to edit the image using QT program? i.e can i modify the image as per my needs dynamically is it possible??

thanks in advance,

regards,
satya

[wysota]

You can access each pixel of the image using QImage API.

[qtlearner123]

hi,

thank you very much for the reply, i am going through the documentation of QImage, but i have one small question suppose i have one image say image1 and i want to remove some part of the image1 and replace it with another image2 can i achieve the task it, based upon your feedback i can make sure i am not going in the wrong direction.

thanks and regards,
satya

[wysota]

You have to open a painter on the image and use QPainter::drawImage() to draw the part that is to replace old content.

[qtlearner123]

you are so precise and to the point.

thanks and regards,
satya

[qtlearner123]

Hi,

iam trying to take image1 and on image1 at some portion i want to overwrite image2, i did with the following code.

#include <QtGui/QApplication>
#include <QLabel>
#include <QGraphicsView>
#include <stdio.h>
#include <QRect>
#include <QPainter>
#include "lines1.h"
 
QImage firstImage;
QImage secondImage;
 
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Lines window;
 
firstImage.load(":/images/myImage1.png");
secondImage.load(":/images/myImage2.png");
window.show();
return a.exec();
}
 
 
void Lines::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
 
    QRect rect1,rect2;
    rect1.setX(0);
    rect1.setY(0);
    rect1.setHeight(600);
    rect1.setWidth(700);
 
    rect2.setX(500);
    rect2.setY(200);
    rect2.setHeight(50);
    rect2.setWidth(50);
 
 
    painter.drawImage(rect1, firstImage);
    painter.drawImage(rect2,secondImage);
}

#include <QtGui/QApplication>
#include <QLabel>
#include <QGraphicsView>
#include <stdio.h>
#include <QRect>
#include <QPainter>
#include "lines1.h"

QImage firstImage;
QImage secondImage;

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
Lines window;

firstImage.load(":/images/myImage1.png");
secondImage.load(":/images/myImage2.png");
window.show();
return a.exec();
}


void Lines::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);

    QRect rect1,rect2;
    rect1.setX(0);
    rect1.setY(0);
    rect1.setHeight(600);
    rect1.setWidth(700);

    rect2.setX(500);
    rect2.setY(200);
    rect2.setHeight(50);
    rect2.setWidth(50);

    
    painter.drawImage(rect1, firstImage);
    painter.drawImage(rect2,secondImage);
}

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my questions are
1. Is it the correct way of doing it or any better method is available to achieve the same?
2. suppose i want to overwrite at a particular part of image how to know the coordinates of those points? right now i am using trial and error method?

thanks in advance,

regards,
satya