If any error occurs when writing the image, write() will return false. Call write() to write the image to the device. canWrite() returns true if QImageWriter can write the image (i.e., the image format is supported and the device is open for writing). You can then set several options, such as quality (by calling setQuality()). Pass either a file name or a device pointer, and the image format to QImageWriter's constructor. To store an image, you start by constructing a QImageWriter object. If you do not need such options, you can use QImage::save() or QPixmap::save() instead. QImageWriter supports setting format specific options, such as compression level and quality, prior to storing the image. SupportsOption(QImageIOHandler::ImageOption option) const SetTransformation(QImageIOHandler::Transformations transform) SetText(const QString & key, const QString & text)

SetProgressiveScanWrite(bool progressive) QImageWriter(QIODevice * device, const QByteArray & format) QImageWriter(const QString & fileName, const QByteArray & format = QByteArray())

Qimage ultimate image read error