Saving QImage

[thgis]

Hi.

I have a problem saving a QImage.
It is generated from a QGraphicsScene via the following code:

QImage image(_scene->sceneRect().size().toSize(), QImage::Format_RGB32);
QPainter painter(&image);
_scene->render(&painter);
image.save(filename);

QImage image(_scene->sceneRect().size().toSize(), QImage::Format_RGB32);
QPainter painter(&image);
_scene->render(&painter);
image.save(filename);

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_scene is a QGraphicsScene*
and filename is a non empty string with the format("filename.png")

image.save(filename) always return false.

Another place in my program I save a QImage generated by setting individual pixels in the QImage and that works fine. (The format here is also .png)

I have tried different formats by changing the filename from filename.png to filename.tiff and so on.

Any ideas?