QImage from QByteArray

[ChristianEhrlicher]

When data.txt contains base64 encoded content, why do you encode it a second time here:

QByteArray base64Data = bytes.toBase64();

And when it's a jpeg - why do you tell QImage::loadFromData() that it's a PNG?

[alexlpn]

When data.txt contains base64 encoded content, why do you encode it a second time here:

And when it's a jpeg - why do you tell QImage::loadFromData() that it's a PNG?

Thanks for pointing this out. I've fixed that but still the result is false...

[ChristianEhrlicher]

QImage::loadFromData() needs the raw data, not base64 encoded text.

[d_stranz]

QImage::loadFromData() needs the raw data, not base64 encoded text.

And so you need to give it the output from QByteArray::fromBase64(), not QByteArray::toBase64().

[alexlpn]

And so you need to give it the output from QByteArray::fromBase64(), not QByteArray::toBase64().

QImage::loadFromData() needs the raw data, not base64 encoded text.

Thank you mates!
I see I've mixed several things in wrong order) Now it is clear.

QFile f("data.txt");
    if (f.open(QIODevice::ReadOnly)){
            qDebug()<<"File was opened";
            QByteArray base64Data = f.readAll();
            QByteArray bytes = QByteArray::fromBase64(base64Data);
 
            QImage image;
            if (image.loadFromData(bytes, "JPG")){
                qDebug()<<"Image was loaded";
            }else{
                qDebug()<<"Image was not loaded";
            }
            QString filename = "output.jpg";
            if (image.save(filename, "JPG")){
                qDebug()<<"Image was saved";
            }else{
                qDebug()<<"Image was not saved";
            }
    }

QFile f("data.txt");
    if (f.open(QIODevice::ReadOnly)){
            qDebug()<<"File was opened";
            QByteArray base64Data = f.readAll();
            QByteArray bytes = QByteArray::fromBase64(base64Data);

            QImage image;
            if (image.loadFromData(bytes, "JPG")){
                qDebug()<<"Image was loaded";
            }else{
                qDebug()<<"Image was not loaded";
            }
            QString filename = "output.jpg";
            if (image.save(filename, "JPG")){
                qDebug()<<"Image was saved";
            }else{
                qDebug()<<"Image was not saved";
            }
    }

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