Re: [Gimp-developer] png save broken in gimp edge ppa - There was an invalid UTF-8 string in the exif:ImageDescription

[Jehan Pagès <jehan marmottard gmail com>]

Hi,

On Mon, May 23, 2016 at 7:59 PM, Thorsten Stettin
<thorsten stettin gmail com> wrote:
> Am 23.05.2016 um 15:00 schrieb C R:
> > Happens every time with this file:
> >
> > http://www.whitecatgraphics.com/opendesignstudio/gimp/samples/ac_a4_document_holder_vintage_leather_brown_4.png
> >
> > steps to reproduce:
> > 1.open the downloaded file in gimp
> > 2.export as "ac_a4_document_holder_vintage_leather_brown_4a.png"
> > 3.these boxes in png export are checked: "save background colour", and all
> > checkboxes after and including Save resolution, compression level 9, and
> > everything under advanced checked.
>
>
> Hi
>
> At home in Xenial I exported your picture with save comment.
> The above error occurred.
> Hmm.
>
> I took a look at the comment field exactly the exif:ImageDescription: It
> contains an invalid UTF-8 string.
>
> *identify -verbose ac_a4_document_holder_vintage_leather_brown_4.png | grep
> -i desc **
> **    exif:ImageDescription: ..:\w.*

According to the Exif spec
(http://www.cipa.jp/std/documents/e/DC-008-2012_E.pdf), even UTF-8
should be invalid. This field is supposed to be ASCII only apparently
(yes that's sucky, definitely). To use multi-byte encoding, such as
UTF-8 (or others such as JIS), the right field is UserComment.

> After replacing the picture comment content with Gimp's standard one - valid
> UTF-8, I think - I could export your picture without any problem.
>
> *identify -verbose ac_a4_document_holder_vintage_leather_brown_4a.png | grep
> -i desc
>     exif:ImageDescription: Created with GIMP*
>
> I guess it's a bug regarding the comment string and/or character set
> handling. Maybe a wrong character set was using in the exif:ImageDescription
> field, I assume.

All this said, it would be good if GIMP were more robust to
otherwise-valid images, even with buggy metadata. In particular, it
should not fail to export, but simply discard the wrong metadata field
with a warning.

Could you please open a bug report about this issue so that we look
into this issue?
Thanks!

Jehan

> Greetings
>
> Thorsten
> > On Mon, May 23, 2016 at 11:24 AM, Thorsten Stettin
> > <thorsten stettin gmail com <mailto:thorsten stettin gmail com>> wrote:
> >
> >     Am 23.05.2016 um 08:44 schrieb C R:
> >     > Fails on export with a Plug-in crash:
> >     >
> >     > "Procedure 'file-png-save-defaults' returned no return values
> >     >
> >     >
> >     > Strangely, if you save as a jpeg first, it exports to png just fine.
> >     >
> >     > Steps to reproduce:
> >     > 1. Open File
> >     > 2. Export to png
> >     >
> >     > Results in the above crash.
> >     >
> >     > Ver: GIMP 2.9.3
> >     > Ubuntu 16.04 with gnome-shell 3.18.4
> >     >
> >     > -C
> >     Under Trusty I can't reproduce that behavior. :-(
> >
> >     gimp Version 2.9.3.81-0t0~ppa
> >     libgegl-0.3-0 1:0.3.6.20-0t0~ppa
> >
> >     Cheers
> >
> >     > _______________________________________________
> >     > gimp-developer-list mailing list
> >     > List address: gimp-developer-list gnome org
> >     <mailto:gimp-developer-list gnome org>
> >     > List membership:
> >     https://mail.gnome.org/mailman/listinfo/gimp-developer-list
> >     > List archives: https://mail.gnome.org/archives/gimp-developer-list
> >
> >
> >     _______________________________________________
> >     gimp-developer-list mailing list
> >     List address: gimp-developer-list gnome org
> >     <mailto:gimp-developer-list gnome org>
> >     List membership:
> >     https://mail.gnome.org/mailman/listinfo/gimp-developer-list
> >     List archives: https://mail.gnome.org/archives/gimp-developer-list
>
>
> --
> Lao-Tse sagt: Nichtstun ist besser, als mit viel Mühe nichts zu schaffen.
> Und er sagt auch: Ich habe drei Schätze, die ich hüte und hege.
> Der eine ist die Liebe, der zweite ist die Genügsamkeit, der dritte ist die
> Demut.
> Nur der Liebende ist mutig, nur der Genügsame ist großzügig, nur der
> Demütige ist fähig zu herrschen.
>
> _______________________________________________
> gimp-developer-list mailing list
> List address:    gimp-developer-list gnome org
> List membership: https://mail.gnome.org/mailman/listinfo/gimp-developer-list
> List archives:   https://mail.gnome.org/archives/gimp-developer-list



-- 
ZeMarmot open animation film
http://film.zemarmot.net
Patreon: https://patreon.com/zemarmot