Comment by laurent123456

There are ways to tell if an image is real, if it's been signed cryptographically by the camera for example, but increasingly it probably won't be possible to tell if something is fake. Even if there's some kind of hidden watermark embedded in the pixels, you can process it with img2img in another tool and get rid of the watermark. Exif data, etc is irrelevant, you can get rid of it easily or fake it.