Re: rotated photos aren't saved

[David Moore <dcm MIT EDU>]

On Fri, 2005-12-02 at 15:08 -0500, John Russell wrote:
> I looked at the exif data after rotating a photo and it did change to
> reflect the rotation.  Apparently gthumb and eog do not respect this
> exif setting which is unfortunate.

Yes, gthumb is seriously broken in this regard.  There are at least two
bugs outstanding on that issue:
http://bugzilla.gnome.org/show_bug.cgi?id=318828
http://bugzilla.gnome.org/show_bug.cgi?id=120839

> Also, what does it meant to rotate a coefficient when exporting? 
> Sorry if that's a stupid question.

By "rotating the coefficients" he means a lossless rotation of the
stored image pixels (as opposed to just changing the exif indicator).
This is done by rotating the stored 8x8 blocks of DCT coefficients in
the JPEG data, hence the term "coefficients."

-David