Could not reproduce (original image is not affected anymore so I tested with the preprocessed one): https://twitter.com/unpixels/status/606509136323477505

If someone sees that bug still in some situation, please report. And those who had some photos affected by this, you can mirror/rotate the image back in some image manipulation program. I'm not sure does the Qt's QImage retain exif data after read -> save operation with same name. If not, I'm sorry for any inconvenience caused by this unintended "feature".