From: nospam@needed.invalid   
      
   On Mon, 12/15/2025 9:20 AM, pinnerite wrote:   
   > GIMP 2.10.36   
   >   
   > I have been scanning articles from a journal.   
   > When I opened them in Gimp, reversed the image that was inverted   
   > and exported the result, they were still inverted. I cannot remember   
   > this being the case in the past.   
   >   
   > I have tried to find a solution via Google but nothing seems to work.   
   >   
   > Alan   
      
   Some image formats, have a metadata bit indicating the   
   image should be rotated. This applies a rotation   
   not captured in the pixmap part.   
      
   The Linux "file" command can tell you something of the image type:   
      
      file mymysterymeat   
      
   JPG file or PNG file or TIFF file  and so on.   
      
   Some scanners produce TIF, some produce PDF, and so on.   
   There are a few options for what you're looking at right now.   
      
   *******   
      
   Let's make up a strawman for you.   
      
   An image has the pixmap rotated. The metadata says to   
   rotate it some more. Alan looks at the image on his   
   screen, and due to the "total 360" degrees of rotation,   
   Alan attaches it to an email and sends it to a friend.   
      
   The friend comments "why did you send me this upside-down   
   image, Alan?". Then, Alan cannot figure out what is amiss,   
   as the image looks just dandy on Alans screen.   
      
   The problem in this case, is viewing tools do not   
   always honour the metadata rotation bit. Alans viewing tool   
   honoured the bit and added the extra rotation, the friend   
   of Alan with a less featureful image viewer, the metadata   
   bit is ignored.   
      
   I think you can see from my little strawman, that it behooves   
   the computer scientist preparing the image, to *remove*   
   the metadata rotation, then apply whatever physical rotation   
   is really needed. *Then*, when the friend receives the photo,   
   it no longer matters whether the friend has an "old" or a "new"   
   image viewer, the picture looks the same in all of them and   
   it also looks like it did on Alans screen.   
      
   Apple likes to save out images, with metadata rotation asserted.   
      
       Paul   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)