> Well, that is different. The problem is you can't name a .jpg file a > .png file. Qt uses file extension for format detection by > default.. QImageReader allows for more control in that.
>From QImage manual (http://doc.qt.io/qt-4.8/qimage.html) - "If the format is not specified (which is the default), the loader probes the file for a HEADER to guess the file format.". Maybe may English is bad, but I'm don't see this a single word about file extension. At least we have wrong manual.