After an evaluation, GNOME has moved from Bugzilla to GitLab. Learn more about GitLab.
No new issues can be reported in GNOME Bugzilla anymore.
To report an issue in a GNOME project, go to GNOME GitLab.
Do not go to GNOME Gitlab for: Bluefish, Doxygen, GnuCash, GStreamer, java-gnome, LDTP, NetworkManager, Tomboy.
Bug 145090 - Saving an image saves alpha channel instead of picture data
Saving an image saves alpha channel instead of picture data
Status: RESOLVED NOTABUG
Product: GIMP
Classification: Other
Component: General
unspecified
Other All
: Normal trivial
: ---
Assigned To: GIMP Bugs
GIMP Bugs
Depends on:
Blocks:
 
 
Reported: 2004-06-28 11:05 UTC by Nils Philippsen
Modified: 2004-12-22 21:47 UTC
See Also:
GNOME target: ---
GNOME version: ---


Attachments
PSD example file (18.34 KB, application/octet-stream)
2004-06-29 07:27 UTC, Nils Philippsen
Details

Description Nils Philippsen 2004-06-28 11:05:15 UTC
Description of Problem:

When saving a picture loaded previously that
contains an alpha channel (a .psd for instance),
the alpha channel is selected by default.
Subsequent saving as PNG gives a (not very
descriptive) error message and apparently saves
the alpha channel.

This bug was reported in Red Hat Bugzilla for
Fedora Core 2 as
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=125946

Steps to reproduce the problem:
1. Load a .psd file (or perhaps another one with
an alpha channel)
2. Save as .png

Actual Results:

Saved image is black (or not, depending on the
alpha channel).

Expected Results:

Saves complete image, eventually warning user
about formats which don't support alpha channels.

How often does this happen? 

Every time.

Additional Information:

Workaround: Select background (or other layer) in
layers dialog.
Comment 1 Sven Neumann 2004-06-28 13:46:03 UTC
This bug report misses the point. The save routine is doing the right thing and
it  tells the user what's happening. If there's a problem at all then it's the
PSD plug-in that selects the channel on load. The question is if the channel is
marked as the active item in the PSD file. In that case the behaviour would be
completely correct. Otherwise the plug-in should probably be changed to select
the topmost layer.

We will need a copy of the PSD file and information on whether the channel was
the selected element in PS (or GIMP) when this file was saved.
Comment 2 Sven Neumann 2004-06-28 13:53:02 UTC
Note also that it's not the alpha channel that is saved. It's an auxilary
channel that represents a saved selection. There's no way to save the alpha
channel only.
Comment 3 Nils Philippsen 2004-06-29 07:27:05 UTC
Created attachment 29080 [details]
PSD example file

Photoshop file that exhibits the problem.
Comment 4 Nils Philippsen 2004-06-29 07:27:32 UTC
The attached file is the one that was attached to the Fedora bug report.
Comment 5 Sven Neumann 2004-06-29 09:35:53 UTC
Well, the important question here is if the channel has been active when the
file has been created.
Comment 6 Sven Neumann 2004-09-13 10:23:17 UTC
This report is waiting for feedback from the bug reporter. Please respond to the
question specified in comment #5.
Comment 7 Sitsofe Wheeler 2004-09-13 15:44:19 UTC
According to a friend with Photoshop 6 on MacOS X, yes it (the attachment in
this bug) does have an active auxilary alpha channel. I'm the original reporter
of the bug in Red Hat's bugzilla.
Comment 8 Sven Neumann 2004-09-13 16:34:49 UTC
The behaviour is not at all surprising then. IMO the plug-in is doing the right
thing. I suggest to close as NOTABUG.
Comment 9 Michael Natterer 2004-10-06 19:29:05 UTC
I don't see what's unclear in the message that pops up.
Closing as NOTABUG.