Convert RGBA8888 buffer to jpeg buffer in memory

[Alien]

Hi,
I've a buffer that contains RGBA888 ,I want to create another buffer that hold the jpeg format according to RGBA buffer with header and data.
I would appreciate any idea.

[A Former User]

Hi!

    // prepare image in RGBA8888 format
    QImage img(600, 400, QImage::Format_RGBA8888);
    {
        img.fill(QColor("white"));
        QPainter painter(&img);
        painter.drawLine(0, 0, 600, 400);
        painter.drawLine(0, 400, 600, 0);
    }

    // save image as JPEG to buffer
    QByteArray ba; // buffer uses ba as its storage
    QBuffer buf(&ba); // we'll use buf as QIODevice
    buf.open(QIODevice::WriteOnly);
    img.save(&buf, "JPEG");

[Alien]

Dear @Wieland ,
Thank you so much.