qml Camera save same image with different resolutions - qt

Question

I'm using QML's Camera component and Camera.imageCapture to save images.
I want to save multiple resolutions of the same image when user click "Capture" button.
The code I'm trying to run is simply like this:
// 160x120
camera.imageCapture.resolution = Qt.size(160,120)
camera.imageCapture.captureToLocation("/location/")
// 320x340
camera.imageCapture.resolution = Qt.size(320,240)
camera.imageCapture.captureToLocation("/anotherLocation/")
camera.imageCapture.resolution = Qt.size(-1,-1) // set to default again
Thanks.

Answer 1

If you'd save your camera input to a QImage you can save and resize and save again using QImage's image.save() and image.scaled() functions.
I've used these functions before for resizing images and it works perfect.
However I don't know how you can save the camera input to a QImage, but I'll look into that and report back.
I know it's not a full answer to your question, but it's a start. I hope that this was helpful.

Answer 2

Here is how I have solved:
Save the image with highest resolution available in Camera:
Component.onCompleted: {
camera.imageCapture.resolution = camera.imageCapture.supportedResolutions[camera.imageCapture.supportedResolutions.length-1]
}
Give the path of that file to the QImage's constructor.
Then scale & save:
Full Code:
imageresizer.cpp:
#include "imageresizer.h"
#include <QImage>
ImageResizer::ImageResizer(QObject *parent) : QObject(parent)
{}
void ImageResizer::resizeImage(int width, int height, QString file, QString savefile)
{
QImage img(file);
img = img.scaled(width, height);
img.save(savefile);
}
imageresizer.h:
#ifndef IMAGERESIZER_H
#define IMAGERESIZER_H
#include <QObject>
class ImageResizer : public QObject
{
Q_OBJECT
public:
explicit ImageResizer(QObject *parent = nullptr);
signals:
public slots:
void resizeImage(int width, int height, QString file, QString savefile);
};
#endif // IMAGERESIZER_H
Don't forget to make it available from QML:
int main(int argc, char *argv[])
{
qmlRegisterType<ImageResizer>("project.imageresizer", 1, 0, "ImageResizer"); // Here
QApplication app(argc, argv);
QQmlApplicationEngine engine;
engine.load(QUrl(QStringLiteral("qrc:/main.qml")));
if (engine.rootObjects().isEmpty())
return -1;
return app.exec();
}
main.qml:
import project.imageresizer 1.0
Window {
id: mainWindow
visible: true
width: 1024
height: 600
title: ""
ImageResizer {
id: imageResizer
}
// Use it like:
// imageResizer.resizeImage(100,100,imgPath,scaleImgPath)
}