Resolution issue with QTextCursor::insertImage ( const QImage & image, const QString & name = QString() )

pika

Hi group,
I'd like to insert a QImage inside a QTextDocument and save it as a PDF file.
To do this i use the QTextCursor::insertImage ( const QImage & image, const QString & name = QString() ) method
but the image is pixelized.
With the same image and with the QTextCursor::insertImage ( const QTextImageFormat & format, QTextFrameFormat::Position alignment ) method it is fine.

there is an example:
@//! Initialise l'imprimante
QPrinter printer;
printer.setOutputFileName(fileDir);
printer.setOutputFormat(QPrinter::PdfFormat);
printer.setPaperSize(QPrinter::A4);
printer.setPageMargins(20,20,20,20, QPrinter::Millimeter);
printer.setColorMode(QPrinter::Color);
printer.setResolution(300);

//! Initialise le document et le style
//! Document
QTextDocument *doc = new QTextDocument();
doc->setPageSize(printer.paperSize(QPrinter::Millimeter));
doc->setDefaultFont(QFont("Arial", 4));
QTextCursor cursor(doc);

QTextImageFormat picture1;
picture1.setName("./imagename.png");
picture1.setWidth(150);

QImage picture2;
picture2.load("./imagename.png");
picture2 = picture2.scaledToWidth(150);

cursor.insertImage(picture1,QTextFrameFormat::InFlow);
cursor.insertText("\n");
cursor.insertImage(picture2);

doc->print(&printer);

@

Does anyone know that issue or does anyone see my mistake?

Thanks

Romain C

Hi Vincent,
I know it's bit too late to give you an answer.
I'm not sure about what I'm giving to you know, but I think this is a normal feature. I explain myself:
I a first way, with a QImage, you make a real transformation on your Image. If your original image have a resolution of 20002000 for example, after setWidth(150);, your image is now a matrix of 150150.

In a another way, with QTextImageFormat, your using a kind of container composed with an image. When you try to resize it with setWidth your operation don't involve a transformation onimage data but only a transform on the container. So, you got the same image (composed of 2000*2000 pixel for example), in a shorter area.
So you are increasing the dpi with this way, data are not reduced, only the size!

Bye!

Romain C

Sorry for double post,
An example to insert a QImage without losing image resolution:

//Adding image to ressource
QUuid uid           = QUuid::createUuid();//Creating a name for our ressource
p_cursor.document()->addResource(QTextDocument::ImageResource, QUrl(uid.toString()), m_markerImage);
//Creating a container for our image and insert it to document
QTextImageFormat format;
format.setName      ( uid.toString());
format.setWidth     ( p_cursor.document()->idealWidth ());
p_cursor.insertBlock( blockFormat, charFormat);
p_cursor.insertImage( format);

I hope it can be useful!
Best regards