Re: [gthumb-list] Extension idea: auto-rotate

[Matthias Hawran <matthias hawran net>]

Dr. Michael J. Chudobiak a écrit :
> On 03/09/2010 03:58 AM, Matthias Hawran wrote:
> > Yes so in fact I'm asking to reintroduce the "Reset Exif orientation"
> > function.
> > I never used this function in 2.10.x
>
> The "Reset Exif orientation" function did something different. All it
> did was reset the exif orientation tag to "top left". It didn't
> physically transform the data.
>
> However, I may have misunderstood what you are trying to do.
>
>
> > > I wouldn't enable it by default, though. Too obscure.
> > What do you mean by "enable"? You mean the extension?
> > What do you mean by "obscure"
>
> If the extension is included with gThumb, it can be enabled or
> disabled by default. I would disable this by default, because the
> average user will not need it, and would be confused by its function.
>
>
> > The [&  ] sequence doesn't fix the images.
> > In 2.10.x it does fix them.
>
> Time for a detailed (step-by-step) bug report with sample images, then.
>
> Orientation tag problems get confusing at times.
>
>
> - Mike

I'm finally continuing this "old" thread.
I must admit to more we discuss, the more I'm lost :-)
Probably I didn't know all the ways images could be rotated, with regard
to exif orientation tag,
in gthumb, including 2.10.x and 2.11.x

I don't know how others see the exif orientation tag, but for me the
primary use is to avoid manually
rotating portrait images.
With this basic requirement I want my portrait images to be shown well
oriented in any software/device.
Fortunately most software handle the tag (gthumb, gimp, eog...)
I've got 2 cases where it doesn't:
- my digital frame (samsung, < 6 months old)
- Facebook

What to do then ?
I have to physically rotate the image and eventually reset the tag to
"top, left"
I would of course like to have this automatic when I import my pictures
from the camera.

Now back to gthumb.
What does the "Rotate image physically" import option do?
According to some tests I did it only rotates the image physically (well
it does what it says duh !)

If I import a portrait orientated picture, exif tag "right-top"

1. Unselect "Rotate image physically"
- Image appears "portrait" oriented
- Orientation tag : "right-top"
- other programs (eog, gimp) open it as portrait

2. Select "Rotate image physically"
- Image appears "landscape" oriented
- Orientation tag : "right-top"
- other programs (eog, gimp) open it as landscape

I don't understand the use of this option if you don't reset the
orientating tag (= set to "top, left") ?

See ImageMagick -auto-orient option:
http://www.imagemagick.org/script/command-line-options.php?#auto-orient

Therefore the idea of an auto-rotate extension: rotate and reset tag.

Cheers,
Matthias