Xournal question

[Rosika (Rosika Schreck)]

Hi all,

I recently introduced a friend of mine (via anydesk) to xournal (GTK+ Application for note taking).

I like using it for conveniently filling in pdf forms and even inserting my personal signature into PDFs.
I know that can also be done with gimp (merging layers) but I find it much more easy to do with xournal.

It works well for me but my friend seemed to have encountered some difficulties employing the “graphics” button for image insertion into a self-composed text.

The imported image was displayed upside down and we found no way to turn it around in xournal.

The thing is: it works perfectly normal with me. I tried it on my system and the image was always inserted the right way.

Does anyone have a clue what might be the cause of this curious problem

Thanks a lot in advance.

Many greetings from Rosika

BTW: My friend and I are both using Linux Lite.

[nevj (Neville Jackson)]

@Rosika

imported image was displayed upside down and we found no way to turn it around in xournal.

Hi Rosika,
I suspect your friend’s image has at some time been rotated before it was imported.
You could test this idea by rotating an image, then importing it. If what I suspect is correct, the importing will remove the rotation.

JPEG Image Orientation and Exif

https://superuser.com/questions/1607310/is-it-possible-to-change-orientation-of-jpg-image-without-rotating-it-and-thus

Can you tell us about this Xournal app. I get that it accepts handwritten input. Do you need a pen and drawing tablet to drive it?
Regards
Neville

[daniel.m.tripp (Dan Tripp)]

@Rosika

imported image was displayed upside down

I concur with @nevj - happens to me sometimes too - I flip an image in shotwell - then go to use it elsewhere, and it’s not flipped, but it shows in Nautilus / Files and Shotwell as flipped…

I think the best way to ensure consistency - is break out the CLI and use imagemagick (e.g. convert, or mogrify) : e.g. :

mogrify -rotate 180 imagefile.jpeg

But I’m guessing your friend is not up to using the CLI ?

[nevj (Neville Jackson)]

@daniel.m.tripp

• I flip an image in shotwell - then go to use it elsewhere, and it’s not flipped, but it shows in Nautilus / Files and Shotwell as flipped…

I think what is happening is… there are 2 ways of rotating an image

• move the pixels
• change the rotation flag in the Exif header
  I think viewers like Shotwell , do the latter if you ask for a regular rotation… like 180 degrees… Then some other program
  might use the image without looking at the header, so it appears unrotated.

A nice mess for someone to sort out.

[nevj (Neville Jackson)]

@daniel.m.tripp

I think the best way to ensure consistency - is break out the CLI and use imagemagick (e.g. convert, or mogrify) : e.g. :

mogrify -rotate 180 imagefile.jpeg

So you are saying Imagemagick will always move the pixels

[daniel.m.tripp (Dan Tripp)]

@nevj

So you are saying Imagemagick will always move the pixels

Yes - it’s “destructive” - but still pretty good… If I don’t want it to “destroy” - I use convert instead of mogrify…

Can’t remember the exact syntax…

Probably not used much any more - but it’s a “traditional” tool used in UNIX since at least the 1980’s or thereabouts… I remember many apache servers hosted on UNIX and Linux systems would have imagemagick scripts in “cgi-bin”… I can remember long ago (circa 2000) getting the source code to build on some Silicon Graphics systems running IRIX that I managed… But then I found MIPS64 IRIX binaries anyway - didn’t need to compile it…

[Rosika (Rosika Schreck)]

Hi @all,

thank you so much for providing such good help.

First of all:

@nevj

Can you tell us about this Xournal app.

Here´s some info:

Xournal is a program for the simple creation of notes, digital notebooks (e-journals) and sketches, which can also be used to edit PDF files.

It behaves like an image editing program that places a transparent level on a background on which you can write and draw.
Data is stored as a file with the .xoj extension.
This can be provided with a PDF file as a background. There is also a function to export as a PDF file.

The program is particularly practical when using a graphic tablet. Since the graphics library GTK+ is used for the interface, it can also be used under Xfce, Mate and LXDE in addition to GNOME.

Functions:

• Pen tool
• etching tool
• Font tool
• Text highlighting
• Outline detection

In an existing journal, further pages can be inserted via “Page - New Page before / after”

(from: Xournal › Wiki › ubuntuusers.de # in German, translated via “firefox translations” add-on )

Further reading:

• https://xournal.sourceforge.net/
• Xournal User's manual

@nevj :

@nevj

I suspect your friend’s image has at some time been rotated before it was imported

That may very well be the case, Neville.
I´ll ask my friend about it next time we talk again.

@nevj

You could test this idea by rotating an image, then importing it. If what I suspect is correct, the importing will remove the rotation.

Sounds like a very good idea. That I will try, of course.

Thanks also for the links, Neville. I´ll look up the information provided by them.

@nevj

change the rotation flag in the Exif header
I think viewers like Shotwell , do the latter if you ask for a regular rotation… like 180 degrees…

This could be verified, can´t it?
… by checking the exif data wit exiftool before and after rotation and then compare the values

@daniel.m.tripp:

@daniel.m.tripp

mogrify -rotate 180 imagefile.jpeg

That´s certainly a promising command. Thanks Dan.

I used the mogrify command in the past, but not the -rotate option. I wouldn´t have thought of that, I have to admit.

I believe I used the command for resizing image files.

@daniel.m.tripp

But I’m guessing your friend is not up to using the CLI ?

Well, not on regular basis, I guess. But that doesn´t matter as we normally connect via anydesk and so I can introduce the respective command to her.
So it shouldn´t be a problem.

I have to wait for her being availbale though, as she´s a high school teacher and the new school term has just begun.

Thanks again so much to all of you for your help.

Many greetings from Rosika

[nevj (Neville Jackson)]

@daniel.m.tripp

Probably not used much any more - but it’s a “traditional” tool used in UNIX since at least the 1980’s or thereabouts

There is a fork called GraphicsMagick… supposed to be better.

[Rosika (Rosika Schreck)]

Thanks, Neville, for bringing this to our attention.

I found it here: http://www.graphicsmagick.org/ .
It´s in ubuntu´s repositories, too.

I´ll look into it.

Cheers from Rosika

[nevj (Neville Jackson)]

@Rosika

This could be verified, can´t it?
… by checking the exif data wit exiftool before and after rotation and then compare the values

Indeed. Anything in the Exif header can be viewed.

Note there are other types of image metadata… there was a post recently discussing them… but I think your issue is Exif.

[Rosika (Rosika Schreck)]

Hi Neville,

I was just looking at an example jpeg file.
I couldn´t find the rotation flag. May it be displayed under another name?

P.S.:

I found “orientation”. That´s certainly it, right?

[nevj (Neville Jackson)]

@Rosika

I found “orientation”. That´s certainly it, right?

Seems right

[Rosika (Rosika Schreck)]

Thanks, Neville.

I´ll do the experiment.

[Rosika (Rosika Schreck)]

Hi again,

I tried it but I can´t spot any difference:

rosika@rosika-Lenovo-H520e ~/Musik [0|1]> exiftool kgw_20Urlaub2023.jpeg | grep -i rotat
Orientation                     : Rotate 90 CW
rosika@rosika-Lenovo-H520e ~/Musik> mogrify -rotate 180 kgw_20Urlaub2023.jpeg 
rosika@rosika-Lenovo-H520e ~/Musik> exiftool kgw_20Urlaub2023.jpeg | grep -i rotat
Orientation                     : Rotate 90 CW

Rotation took place however. So the mogify command worked.

Cheers from Rosika

[nevj (Neville Jackson)]

@Rosika

can´t spot any difference

Because imagemagick does not change the Exif flag, it actually moves the pixels around in the image.

[Rosika (Rosika Schreck)]

O.K., Neville. That´s the explanation. Thanks.

shotwell doesn´t change it either it seems:

I opened up the image file in shotwell, applied the “flip vertically” button and looked at the outcome.

rosika@rosika-Lenovo-H520e ~/Musik> firejail --private=(pwd) shotwell
[...]
Parent is shutting down, bye...
rosika@rosika-Lenovo-H520e ~/Musik> exiftool kgw_20Urlaub2023.jpeg | grep -i rotat
Orientation                     : Rotate 90 CW

After shutting down shotwell the image rermains turned around.
So: no EXIF data change here either.

Thanks again and cheers from Rosika

[nevj (Neville Jackson)]

@Rosika

So: no EXIF data change here either.

I am surprised, I thought shotwell might flip the exif flag
live and learn