gimp 1.3.18 - Pink backgrounds on GIF's
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gimp 1.3.18 - Pink backgrounds on GIF's
Hello, Everyone :)
I've had this problem for the last two development versions of the Gimp:
1.3.17 and 1.3.18
Hopefully, to maximize the clarity of the information that I have to
give you, and minimize the size of this e-mail, I will proceed with a
series of links to screen shots and brief, appropriate comments.
1. For the sake of accuracy, I first include a screen-shot of GIF that has this problem, as viewed in a non-Gimp application: Gqview 1.3.2 http://www.faith4miracle.org/01-GimpSS-GQVIEW.jpg You will notice that the background is transparent, as represented by the grey/light gray checks. No problem here.
2. Next, I opened up the exact same image with Gimp 1.2.3, the version that ships by default with Red Hat 9: http://www.faith4miracle.org/02-GimpSS-gimp-1.2.3.jpg Just like in example 1, it displays properly.
3. Next, with the exact same image as in all the other examples, the current stable version of the Gimp: Gimp 1.2.5: http://www.faith4miracle.org/03-GimpSS-gimp-1.2.5.jpg Again, no problem.
4. Next, the oldest Gimp development version I have installed on my
system: Gimp 1.3.16:
http://www.faith4miracle.org/04-GimpSS-gimp-1.3.16.jpg
Again, no problem.
Here is where the problems start, with Gimp 1.3.17 and 1.3.18:
5. Gimp 1.3.17: http://www.faith4miracle.org/05-GimpSS-gimp-1.3.17.jpg As you can clearly see, the background is now pink.
6. Gimp 1.3.18: http://www.faith4miracle.org/06-GimpSS-gimp-1.3.18.jpg As in example 5, the background is pink.
Before I move on, to clarify, in the making of all these screen-shots,
I used the exact same image.
I can manipulate, copy, paste, etc, the image just fine if I use one of
the first three versions of the Gimp mentioned above. But if I edit the
image in the two most recent development versions of the Gimp (1.3.17
and 1.3.18), the background permanently becomes pink.
If someone were to suggest that there was an issue with the way that I
made it (I cropped it using a program in Windows, and exported the
actual GIF that you see in the screen-shots from an OpenOffice.org
Impress presentation slide.), I would have to point out that it displays
and edits perfectly in three of the five versions of the Gimp that I
tried it on.
If you have any questions for me, I am more than happy to answer
anything you may have to ask me.
I checked bugzilla.gnome.org and I found nothing but a reference to an
apparently similar issue with an animated GIF. When I grabbed that
image and opened it up in Gimp 1.3.17 and 1.3.18, I saw absolutely
nothing wrong with it. The background is transparent on my system, so
as a result, I Assume that my problem is different :)
I am running Red Hat 9, with every package installed. (That's almost
1400 packages) I have all the official Red Hat updates installed. As
far as gtk+ and gtk2, I have the versions that ship with Red Hat 9
installed.
If something relating to a known dependency is affecting Gimp 1.3.17
and 1.3.18 on Red Hat 9, I do apologize and if you say so, I will try
upgrading to newer versions. The reason I haven't yet is because I've
had really bad luck upgrading Gtk related items in the past. But if you
say so, with your expert guidance, I will gladly try again :)
Steven P. Ulrick
gimp 1.3.18 - Pink backgrounds on GIF's
Can you provide a copy of the GIF in question?
To be clear, this only happens to the GIF when when you SAVE it out from .17 or .18? If so, do you see any warnings on the console when you save from these versions?
--Adam
gimp 1.3.18 - Pink backgrounds on GIF's
On Mon, 11 Aug 2003 10:58:10 +0100 "Adam D. Moss" wrote:
Can you provide a copy of the GIF in question?
To be clear, this only happens to the GIF when when you SAVE it out from .17 or .18? If so, do you see any warnings on the console when you save from these versions?
--Adam
gimp 1.3.18 - Pink backgrounds on GIF's
On 11 Aug 2003, at 4:26, Steven P. Ulrick wrote:
I've had this problem for the last two development versions of the Gimp: 1.3.17 and 1.3.18
Hopefully, to maximize the clarity of the information that I have to give you, and minimize the size of this e-mail, I will proceed with a series of links to screen shots and brief, appropriate comments.1. For the sake of accuracy, I first include a screen-shot of GIF that has this problem, as viewed in a non-Gimp application: Gqview 1.3.2 http://www.faith4miracle.org/01-GimpSS-GQVIEW.jpg You will notice that the background is transparent, as represented by the grey/light gray checks. No problem here.
[...]
5. Gimp 1.3.17:
http://www.faith4miracle.org/05-GimpSS-gimp-1.3.17.jpg As you can clearly see, the background is now pink.
Starting 1.3.17, the GIF plug-in has been changed in the following way (from plug-ins/common/gif.c, spacing edited to accommodate wrapping):
" * REVISION HISTORY
*
* 2003-06-16
* 4.01.00 - Attempt to use the palette colour closest to
* that of the GIMP's current brush background
* colour for the GIF file's background index
* hint for non-transparency-aware image
* viewers. NOTE that this is merely a hint
* and may be ignored by this plugin for
* various (rare) reasons that would usually
* entail writing a somewhat larger image
* file."
This may be related.
gimp 1.3.18 - Pink backgrounds on GIF's
On Mon, 11 Aug 2003 12:30:10 +0100 "Adam D. Moss" wrote:
Steven P. Ulrick wrote:
...
the image always displays properly before I open it in Gimp 1.3.17 or 1.3.18. Whenever I have saved one of the images that was given a pink background instead of a transparent one, there has been absolutely no error messages whatsoever.
At what point is an image 'given' a pink background?
Hello, Adam :)
The image is first given a pink background in the preview before it is
even opened. Here is an experiment I just tried:
1. Open up Gimp 1.2.3 and Gimp 1.3.18 (Examples of Gimp versions that
deal with this issure correctly and incorrectly)
2. In Gimp 1.2.3, click "File | Open" and choose the desired image.
3. In the preview box, before the image is even opened, the image
displays correctly, with a transparent background. Remember, this is in
the Preview, before it's even opened.
4. At this point, we have seen that the image itself has a transparent
background. So let's move on to the next step.
5. In Gimp 1.3.18, click "File | Open" and choose the desired image,
6. In the preview box, before the image is opened, the background is
already pink.
7. Just for fun, without resaving the image we just opened twice, reopen
the image that you just saw with a pink background with Gimp 1.2.3. You
will notice that the background is still transparent.
Okay, now open up the orginal image:
http://www.faith4miracle.org/FaithLogo-circle.gif
in Gimp 1.3.18 and save it under a different name. (You could save it under the same name if you wanted, but of course if you wanted to investigate this further, you'd need to get a new copy :)) Now, since you saved the formerly background-less image in the Gimp version that attatches a pink background to transparent GIF's, the image has a pink background in every version of the Gimp. It has become a permanent part of the image.
How do I reproduce the problem -- would I be right in thinking that if I load the GIF above, then re-save it again and re-load the result then the resulting GIF will have a pink background?
I answered this question in my response above, but to reiterate, the answer is "yes", if you resave the image in Gimp 1.3.18 and reload it in any version of the Gimp, GQview, ImageMagick, whatever, it now has a pink background.
As an experiment, in a few hours, I'm going to take the original logo I cut the Circle image out of, and use the same program in Windows that I cropped the circle part out to begin with, and then save it as a transparent GIF and run the same tests with that. This is just in case something funny has happened to the image itself. Which of course only changes the problem slightly.... But at least it may eliminate some possibilities :)
Steven P. Ulrick
gimp 1.3.18 - Pink backgrounds on GIF's
Steven P. Ulrick wrote:
How do I reproduce the problem -- would I be right in thinking that if I load the GIF above, then re-save it again and re-load the result then the resulting GIF will have a pink background?
I answered this question in my response above, but to reiterate, the answer is "yes", if you resave the image in Gimp 1.3.18 and reload it in any version of the Gimp, GQview, ImageMagick, whatever, it now has a pink background.
Okay, in that case I think I must have made a mistake in the forward-port of the 1.2.x fix to 1.3.x, because I can't reproduce this in my 1.2.x tree with the equivilent GIF plugin 4.01.00 fix in it.
I'll try to spot what the forward-port does differently.
--Adam
gimp 1.3.18 - Pink backgrounds on GIF's
Adam D. Moss wrote:
Okay, in that case I think I must have made a mistake in the forward-port of the 1.2.x fix to 1.3.x, because I can't reproduce this in my 1.2.x tree with the equivilent GIF plugin 4.01.00 fix in it.
I'll try to spot what the forward-port does differently.
I can't see anything wrong with the forward-port, and still can't reproduce this with the same mod on the 1.2.x branch. Now I can't afford any more time to look into this in the near future.
Maybe someone who can reproduce this in 1.3.18 can come up with some ideas.
Here's the unpublished 1.2.x gif-save plugin with the same fix that went into 1.3.17 (which I'm ASSUMING is the fix that is at the root of this problem), for comparison: http://icculus.org/~aspirin/gif.c
--Adam
gimp 1.3.18 - Pink backgrounds on GIF's
On Mon, 2003-08-11 at 07:33, Adam D. Moss wrote:
Adam D. Moss wrote:
Okay, in that case I think I must have made a mistake in the forward-port of the 1.2.x fix to 1.3.x, because I can't reproduce this in my 1.2.x tree with the equivilent GIF plugin 4.01.00 fix in it.
I'll try to spot what the forward-port does differently.
I can't see anything wrong with the forward-port, and still can't reproduce this with the same mod on the 1.2.x branch. Now I can't afford any more time to look into this in the near future.
Maybe someone who can reproduce this in 1.3.18 can come up with some ideas.
Here's the unpublished 1.2.x gif-save plugin with the same fix that went into 1.3.17 (which I'm ASSUMING is the fix that is at the root of this problem), for comparison: http://icculus.org/~aspirin/gif.c
--Adam
Without getting fancy, I just tried this image in gimp-1.3.18 (Linux, RedHat 9). It opened with the pink background, but I could repair the transparency by (a) adding an alpha channel in the Layers and Channels Dialog and (b) select by color/clear selection.
Is the problem as simple as losing the alpha channel from the GIF in the later versions?
gimp 1.3.18 - Pink backgrounds on GIF's
Hi.
Jeff Trefftzs wrote:
Without getting fancy, I just tried this image in gimp-1.3.18 (Linux, RedHat 9). It opened with the pink background
Wait, it OPENED with the pink background? You didn't have to save it out again first?
gimp 1.3.18 - Pink backgrounds on GIF's
On Mon, 2003-08-11 at 08:49, Adam D. Moss wrote:
Hi.
Jeff Trefftzs wrote:
Without getting fancy, I just tried this image in gimp-1.3.18 (Linux, RedHat 9). It opened with the pink background
Wait, it OPENED with the pink background? You didn't have to save it out again first?
Yes indeedy!
I downloaded the GIF from the URL you provided. When I opened it in gimp-1.3.17 (yes, 17, not 18, my bad) it showed the pink bg. Both in preview and when I opened it. This duplicates the reported behavior, btw.
gimp 1.3.18 - Pink backgrounds on GIF's
It is probably this checkin:
http://cvs.gnome.org/bonsai/cvsview2.cgi?diff_mode=context&whitespace_mode=show&file=gifload.c&branch=&root=/cvs/gnome&subdir=/gimp/plug-ins/common&command=DIFF_FRAMESET&rev1=1.30&rev2=1.31
The guchar -> gchar change without correcting the code using the buf isn't probably good idea?
Tom
gimp 1.3.18 - Pink backgrounds on GIF's
Jeff Trefftzs wrote:
On Mon, 2003-08-11 at 08:49, Adam D. Moss wrote:
Hi.
Jeff Trefftzs wrote:
Without getting fancy, I just tried this image in gimp-1.3.18 (Linux, RedHat 9). It opened with the pink background
Wait, it OPENED with the pink background? You didn't have to save it out again first?
Yes indeedy!
I downloaded the GIF from the URL you provided.
(n.b. I didn't provide a URL, I didn't report the bug)
> When I opened it in
gimp-1.3.17 (yes, 17, not 18, my bad) it showed the pink bg. Both in preview and when I opened it. This duplicates the reported behavior, btw.
Okay, that's a pretty vital difference (and the reason I asked for clarification from the original reporter about whether it requires a save-then-reload, which he said it did in contradiction to what you've just reported, hence my general confusion). This means it's a gifload.c bug, not a gif.c bug (my last change to gifload.c was strictly a LZW bugfix so I can't see a potential problem there, but I'll try to look into it :( ).
Thanks,
--Adam
gimp 1.3.18 - Pink backgrounds on GIF's
Tom Mraz wrote:
It is probably this checkin:
http://cvs.gnome.org/bonsai/cvsview2.cgi?diff_mode=context&whitespace_mode=show&file=gifload.c&branch=&root=/cvs/gnome&subdir=/gimp/plug-ins/common&command=DIFF_FRAMESET&rev1=1.30&rev2=1.31The guchar -> gchar change without correcting the code using the buf isn't probably good idea?
I think you're right. That bogus change totally sneaked under my radar... (heads will roll! :D :D :D )
If someone who sees the problem can test this fix: http://icculus.org/~aspirin/gifload.c that'd be good.
Thanks, --Adam
gimp 1.3.18 - Pink backgrounds on GIF's
Adam D. Moss wrote:
Tom Mraz wrote:
The guchar -> gchar change without correcting the code using the buf isn't probably good idea?
I think you're right. That bogus change totally sneaked under my radar... (heads will roll! :D :D :D )
If someone who sees the problem can test this fix: http://icculus.org/~aspirin/gifload.c that'd be good.
I've tested it and it fixes the bug.
Tom Mraz
gimp 1.3.18 - Pink backgrounds on GIF's
Tom Mraz wrote:
If someone who sees the problem can test this fix: http://icculus.org/~aspirin/gifload.c that'd be good.
I've tested it and it fixes the bug.
Thanks all, the fix is in.
--Adam
