Under Windows I am running into a problem where the GIMP's pixel buffer seems to hit a 2GB file size limit when my gray scale TIFF image files excede roughly 400KB in size. I'm guessing the buffer requires 5 bytes per pixel (RGB, transparency, ?), even though all of that isn't really needed for my images.

I need to work with these images absolutely ASAP. Because all of the machines involved are running Windoze, I was hoping to stick with that. However, it's starting to look like that is a hopeless cause given my poor porting skills and the apparant lack of interest of most gimp developers in addressing this problem under Windoze (at least in the near term).

So, I'm starting to consider using Linux instead, and have two related questions:

1. Can anyone out there positively confirm that running the GIMP under a fairly recent version of Linux would avoid any inherent 2GB pixel buffer size limit? I can provide some images for testing if anyone would like to volunteer...

2. Would anyone out there care to suggest a readily available commercial Linux distribution that is extremely easy to install, learn, and use for unsophisticated users with primarily Windblows experience?

Thanks in advance for any help.

s/KAM

Hmmm,

Ok, here is what seems to be happening: When the size of the vertical axis (I didn't test horizontal) exceeds somwhere around 2250 inches, the gimp dies or locks up. It doesn't seem to matter what the size of the file is, and it doesn't matter how many pixels there are.

Using File -> New, both 1024 x 162000 pixels at 72 dpi and 1024 x 450000 pixels at 200 dpi work fine, while both 1024 x 163000 pixels at 72 dpi and 1024 x 453000 pixels at 200 dpi fail. I have no idea exactly what could be causing this, but obviously an overflow or overrun of some type seems likely.

Any gimp developers out there care to take a look at this? I'm running 1.2.4 under Win 2K. Fred was running under Suse Linux 8.0 I believe.

Thanks in advance, s/KAM

----- Original Message ----- From: "Kevin Myers"
To:
Cc: "gimp users" ; "gimpwin users"

Sent: Thursday, January 09, 2003 12:35 AM Subject: Re: [Gimp-user] GIMP Image Size Limits

Hi Fred -

Thanks for the info. Just encountered some rather surprising results on

my

own system, and sent you a separate note regarding that. Your results are similar to what I experienced previously on my system, but at around 400MB instead of 273MB. FWIW, I have 1.5GB of RAM on my Win 2K based system.

Now

I am even more confused! I'll do some more testing and let you know what

I

figure out...

Thanks again, s/KAM

----- Original Message ----- From: "Fred Bazolo"
To:
Sent: Thursday, January 09, 2003 12:30 AM Subject: Re: [Gimp-user] GIMP Image Size Limits

Kevin,

I may be able to save you the trouble.

While I was waiting, I went ahead and just tried to make some 400 MB tiff files. I got as high as 273MB and my system didn't like it, but it did it.

Above that, the GIMP just died and went away - literally! I set the preferences so as to allow as much free memory as possible but that's the best I'm able to do. So I wonder, is there some sort of ~300 MB limit with tiff files, or is it just my system, or the way I had things set up. Don't know.

I was using color tiffs if that is useful.

On Thursday 09 January 2003 00:26, Kevin Myers wrote:

Hi Fred -

Fortunately, it isn't actually necessary to use a 400+MB file to test

for

the problem. I am uploading a 500M pixel file to an ftp site that I

will

point you to shortly. This file is 1 bit per pixel and using group 4 compression is only about 6MB in size. Hopefully that will download a

lot

faster, and it will still trigger the 2GB pixel cache limit if it exists (500M pixels * 5 bytes per pixel = 2.5GB).

Thanks for your help!

s/KAM

----- Original Message ----- From: "Fred Bazolo"
To: "gimp users"
Sent: Wednesday, January 08, 2003 11:22 PM Subject: Re: [Gimp-user] GIMP Image Size Limits

Whew! That would be a test of my system!

Like I mentioned earlier, the largest files I ever tried to work with

were

about 100 MB, and although it worked it was too annoying to bother with.

But it would be fun to try a 400 mb file. I could just set the

preferences

parameters really high, close down everything else and see what happens.

It will take a few minutes just to download a 400 mb file!

On Thursday 09 January 2003 00:11, Kevin Myers wrote:

Sorry Fred and all, my apologies, 400KB was a serious typo. That

should

have read 400MB!

s/KAM

----- Original Message ----- From: "Fred Bazolo"
To: "gimp users"
Sent: Wednesday, January 08, 2003 11:12 PM Subject: Re: [Gimp-user] GIMP Image Size Limits

I am curious about your file sizes though: 400 KB doesn't sound all

that

big;
actually, that sounds pretty small. Also, I'm not very technical so

bear

with
me, but isn't 5 times 400 KB about 2.0 MB? What am I missing here?

On Wednesday 08 January 2003 23:31, Kevin Myers wrote:

Under Windows I am running into a problem where the GIMP's pixel

buffer

seems to hit a 2GB file size limit when my gray scale TIFF image

files

excede roughly 400KB in size. I'm guessing the buffer requires 5

bytes

per

pixel (RGB, transparency, ?), even though all of that isn't really

needed

for my images.

I need to work with these images absolutely ASAP. Because all of

the

machines involved are running Windoze, I was hoping to stick with

that.

However, it's starting to look like that is a hopeless cause given

my

poor porting skills and the apparant lack of interest of most gimp developers

in

addressing this problem under Windoze (at least in the near term).

So, I'm starting to consider using Linux instead, and have two

related

questions:

1. Can anyone out there positively confirm that running the GIMP

under

a fairly recent version of Linux would avoid any inherent 2GB pixel buffer size limit? I can provide some images for testing if anyone would like to volunteer...

2. Would anyone out there care to suggest a readily available commercial Linux distribution that is extremely easy to install,

learn,

and use for unsophisticated users with primarily Windblows

experience?

Thanks in advance for any help.

s/KAM

Hi Sven,

Thanks for your reply. My tile cache size is set to 1GB (I have 1.5GB of RAM), which should theoretically help based on your comments. Also, upon further testing I have found that the problem I am encountering seems to be related to the physical dimensions of the image, rather than the file size or pixel count. For example, the GIMP is failing when the height of the image exceeds about 187.5 feet, regardless of whether using 72 dpi or 200 dpi.

I would be very willing to try the 1.3x source track. Unfortunately, I am limited to running under Windows at the moment, and my understanding is that 1.3x has not yet been ported to Windows, and that porting would be far too difficult for my amateur level porting skills.

Thanks again for your comments.

Regards, s/KAM

----- Original Message ----- From: "Sven Neumann"
To: "Kevin Myers"
Cc: "gimp users" ; "gimp developers" ; "gimpwin developers"

Sent: Thursday, January 09, 2003 5:22 AM Subject: Re: [Gimp-developer] GIMP Image Size Limits

Hi,

"Kevin Myers" writes:

Under Windows I am running into a problem where the GIMP's pixel buffer seems to hit a 2GB file size limit when my gray scale TIFF image files excede roughly 400KB in size. I'm guessing the buffer requires 5 bytes per pixel (RGB, transparency, ?), even though all of that isn't really needed for my images.

did you increase the tile cache size? Otherwise you are not using much of your RAM and almost all the tile data ends up in the swap file which is indeed limited to 2GB (see below).

1. Can anyone out there positively confirm that running the GIMP under a fairly recent version of Linux would avoid any inherent 2GB pixel buffer size limit? I can provide some images for testing if anyone would like to volunteer...

I can definitely tell you that GIMP-1.2 as well as GIMP-1.3 up to version 1.3.11 have the same problem on whatever platform you use them. See http://bugzilla.gnome.org/show_bug.cgi?id=74478

I have finally fixed this in CVS last weekend and successfully tested with the swap files growing to almost 5 GB. The fix will in the 1.3.12 release. If you need it now, you will have to use GIMP from CVS. You should however note that this is an unstable development tree and there certainly are bugs in GIMP-1.3.

Salut, Sven

Nope, the limit in preferences that you refer to applies to file size rather than physical image dimensions (which is where my problem is cropping up). Exceeding the file size limit only produces a warning, not an error. Thanks anyway. :-)

I'll probably enter the apparant dimension limit as a gimp bug as soon as I get half a chance.

s/KAM

----- Original Message ----- From: CHARLES MCCHESNEY
To: gimpwin-users@yahoogroups.com
Sent: Thursday, January 09, 2003 3:44 PM Subject: Re: [gimpwin-users] Re: [Gimp-user] GIMP Image Size Limits

u know under preferences there is a place where the maximum size of a picture can be set. maybe ur going over what's set in your preferences. Charles McChesney

Kevin Myers wrote:

Hmmm,

Ok, here is what seems to be happening: When the size of the vertical axis
(I didn't test horizontal) exceeds somwhere around 2250 inches, the gimp dies or locks up. It doesn't seem to matter what the size of the file is,
and it doesn't matter how many pixels there are.

Using File -> New, both 1024 x 162000 pixels at 72 dpi and 1024 x 450000 pixels at 200 dpi work fine, while both 1024 x 163000 pixels at 72 dpi and
1024 x 453000 pixels at 200 dpi fail. I have no idea exactly what could be
causing this, but obviously an overflow or overrun of some type seems likely.

Any gimp developers out there care to take a look at this? I'm running 1.2.4 under Win 2K. Fred was running under Suse Linux 8.0 I believe.

Thanks in advance, s/KAM

----- Original Message ----- From: "Kevin Myers" <! ;KevinMyers@austin.rr.com> To:
Cc: "gimp users" ; "gimpwin users"
Sent: Thursday, January 09, 2003 12:35 AM Subject: Re: [Gimp-user] GIMP Image Size Limits

> Hi Fred - >
> Thanks for the info. Just encountered some rather surprising results on
my
> own system, and sent you a separate note regarding that. Your results are
> similar to what I experienced previously on my system, but at around 400MB
> instead of 273MB. FWIW, I have 1.5GB of RAM on my Win 2K based system.
Now
> I am even more confused! I'll do some more testing and let you know what
I
> figure out...
>
> Thanks again,
> s/KAM
>
>
> ----- Original Message -----
> From: "Fred Bazolo"
> To: > Sent: Thursday, January 09, 2003 12:30 AM
> Subject: Re: [Gimp-user] GIMP Image Size Limits >
>
>
> Kevin,
>
> I may be able to save you the trouble. >
> While I was waiting, I went ahead and just tried to make some 400 MB tiff
> files. I got as high as 273MB and my system didn't like it, but it did it.
>
> Above that, the GIMP just died and went away - literally! I set the > preferences so as to allow as much free memory as possible but that's the
> best I'm able to do. So I wonder, is there some sort of ~300 MB limit with
> tiff files, or is it just my system, or the way I had things set up. Don't
> know.
>
> I was using color tiffs if that is useful. >
> On Thursday 09 January 2003 00:26, Kevin Myers wrote: > > Hi Fred -
> >
> > Fortunately, it isn't actually necessary to use a 400+MB file to test
for
> > th! e problem. I am uploading a 500M pixel file to an ftp site that I
will
> > point you to shortly. This file is 1 bit per pixel and using group 4
> > compression is only about 6MB in size. Hopefully that will download a
lot
> > faster, and it will still trigger the 2GB pixel cache limit if it exists
> > (500M pixels * 5 bytes per pixel = 2.5GB). > >
> > Thanks for your help!
> >
> > s/KAM
> >
> >
> > ----- Original Message ----- > > From: "Fred Bazolo"
> > To: "gimp users"
> > Sent: Wednesday, January 08, 2003 11:22 PM > > Subject: Re: [Gimp-user] GIMP Image Size Limits > >
> >
> > Whew! That would be a test of my system! > >
> > Like I mentioned earlier, the largest files I ever tried to work with
were> > about 100 MB, and although it worked it was too annoying to bother with.
> >
> > But it would be fun to try a 400 mb file. I could just set the preferences
> > parameters really high, close down everything else and see what happens.
> >
> > It will take a few minutes just to download a 400 mb file! > >
> > On Thursday 09 January 2003 00:11, Kevin Myers wrote: > > > Sorry Fred and all, my apologies, 400KB was a serious typo. That should
> > > have read 400MB!
> > >
> > > s/KAM
> > >
> > >
> > > ----- Original Message ----- > > > From: "Fred Bazolo"
> > > To: "gimp users"
> > > Sent: Wednesday, January 08, 2003 11:12 PM > > > Subject: Re: [Gimp-user] GIMP Image Size Limits > > >
&! gt; > >
> > > I am curious about your file sizes though: 400 KB doesn't sound all
that
> > > big;
> > > actually, that sounds pretty small. Also, I'm not very technical so
bear
> > > with
> > > me, but isn't 5 times 400 KB about 2.0 MB? What am I missing here? > > >
> > > On Wednesday 08 January 2003 23:31, Kevin Myers wrote: > > > > Under Windows I am running into a problem where the GIMP's pixel > buffer
> > > > seems to hit a 2GB file size limit when my gray scale TIFF image files
> > > > excede roughly 400KB in size. I'm guessing the buffer requires 5
> bytes
> > >
> > > per
> > >
> > > > pixel (RGB, transparency, ?), even though all of that isn't really
> >
> > needed
> >
> > > > for my images.
> > > >> > > > I need to work with these images absolutely ASAP. Because all of
the
> > > > machines involved are running Windoze, I was hoping to stick with
> that.
> > > > However, it's starting to look like that is a hopeless cause given
my
> > > > poor porting skills and the apparant lack of interest of most gimp
> > > > developers
> > >
> > > in
> > >
> > > > addressing this problem under Windoze (at least in the near term).
> > > >
> > > > So, I'm starting to consider using Linux instead, and have two related
> > > > questions:
> > > >
> > > > 1. Can anyone out there positively confirm that running the GIMP under
> > > > a fairly recent version of Linux would avoid any inherent 2GB pixel
> > > > buffer size limit? I can p! rovide some images for testing if anyone
> > > > would like to volunteer... > > > >
> > > > 2. Would anyone out there care to suggest a readily available > > > > commercial Linux distribution that is extremely easy to install, > learn,
> > > > and use for unsophisticated users with primarily Windblows experience?
> > > >
> > > > Thanks in advance for any help. > > > >
> > > > s/KAM
> > > >
> > > >
> > > >

Hi Sven -

My images are extremely long and relatively narrow, not anywhere near square. A typical image size would be approximately 200K pixels in length (height), by only 2K pixels in length, for a total image size of about 400M pixels. I have some images over 600M pixels, while others are somewhat smaller.

Yes, some of these images exceed 200ft in length. You may be wondering what they could be: images of well logs for oil and gas wells. These are essentially strip chart (graphical) recordings of various physical properties taken over the length of the borehole. They are rather drastically scaled down already (typically 1 inch represents somewhere between 20 to 100 feet) in the vertical dimension, and detail is important, so further scale reduction is NOT practical. It is also impractical for other reasons that are too complex to get into here to split the images up into smaller sections.

Bottom line: Again, I must state that the problem I am encountering is NOT related to the pixel count or file size! It occurs when the number of pixels on ONE axis multiplied by the resolution exceeds approximately 187.5 feet in length.

Thanks for your comments re GIMP 1.3.x. Your positive impressions are somewhat surprising to me, since comments from Tor Lilqvist (the primary porter of GIMP 1.2.x to Windows), led me to believe that porting 1.3.x to Windows was going to be very difficult. Something to do with library interdependencies and lack of related tools under Windows if I remember correctly. Since Tor's porting skills are far beyond my own, and he's been involved with porting the GIMP for quite a while now, I tend to respect his opinions. However, anyone can occasionally miss something, especially if they are too busy with other things. Do you know anywhere I could find some instructions for installing GIMP 1.3.x under Windows?

s/KAM

----- Original Message ----- From: "Sven Neumann"
To: "Kevin Myers"
Cc: "gimp users" ; "gimp developers"

Sent: Friday, January 10, 2003 4:46 AM Subject: Re: [Gimp-developer] GIMP Image Size Limits

Hi,

"Kevin Myers" writes:

Thanks for your reply. My tile cache size is set to 1GB (I have 1.5GB of RAM), which should theoretically help based on your comments. Also, upon further testing I have found that the problem I am encountering seems to be related to the physical dimensions of the image, rather than the file size or pixel count. For example, the GIMP is failing when the height of the image exceeds about 187.5 feet, regardless of whether using 72 dpi or 200 dpi.

are you saying 188 _feet_ ? That would make about 162000 pixels of image height. How wide are these images? If I'd assume the same width, a single RGB layer would have more than 75GB of image data. Your operating system is not even able to address the amount of virtual memory you'd need to work with such a beast.

I would be very willing to try the 1.3x source track. Unfortunately, I am limited to running under Windows at the moment, and my understanding is that 1.3x has not yet been ported to Windows, and that porting would be far too difficult for my amateur level porting skills.

this is not true; actually the situation is the other way around. While GIMP-1.2 needed real porting work, all the libraries required by GIMP-1.3 now officially support the Win32 platform and it shouldn't be too difficult to get the GIMP-1.3 source compiled on Windows.

Salut, Sven

As it turns out, ImageMagick runs into problems with these images before the GIMP does. ImageMagick ALWAYS reserves 5 bytes per pixel when working with a Q8 image (even if grayscale), and runs into the 2GB file size limit with 400MB images as a result. The GIMP does not have this problem when dealing with grayscale images, because it doesn't reserve 5 bytes per pixel like ImageMagick does. Unfortunately, the GIMP still runs into some other kind of problem when the physical length of any one dimension of the image exceeds about 187.5 feet, but this is NOT a file size or pixel count limit. I can trick the GIMP into working with an image that it would otherwise have problems with by merely increasing the dpi in the metadata for the file, thereby fooling the GIMP into thinking that the physical dimensions of the image are smaller than they really are.

Another reason for using the GIMP is that I must also be able to DISPLAY these images and work with them to some degree interactively. ImageMagick can't handle these requirements.

It should be noted that there ARE other programs available that can work with images of this size with no difficulty at all, even on systems with relatively little RAM. They do this by NOT attempting to load the whole image into memory at once, but instead only working with smaller chunks at once. However, all of the programs that I am aware of in this category have one of two problems where my use is concerned: 1) they are either prohibitively expensive, or 2) they don't have the capabilities that I need. Right now, the GIMP, despite it's imperfections, is the closest thing that I have found to meeting my needs, so far...

If I could just get this one bug fixed, then the GIMP could do most everything that I need. In the meantime, I've developed a separate tool to help me work around the problem by changing the dpi values without resampling or changing the total pixel count.

s/KAM

----- Original Message ----- From: "Steinar H. Gunderson"
To: "gimp developers"
Sent: Friday, January 10, 2003 5:17 AM Subject: Re: [Gimp-developer] GIMP Image Size Limits

On Fri, Jan 10, 2003 at 05:13:31AM -0600, Kevin Myers wrote:

Yes, some of these images exceed 200ft in length. You may be wondering

what

they could be: images of well logs for oil and gas wells. These are essentially strip chart (graphical) recordings of various physical properties taken over the length of the borehole.

Are you sure you want to use GIMP to work with this sort of things anyhow? What really do you want to do to them -- are you sure ImageMagick wouldn't

be

a better choice for most operations?

/* Steinar */ --
Homepage: http://www.sesse.net/

----- Original Message -----
From: "Sven Neumann"
To: "Kevin Myers"
Cc: "gimp users" ; "gimp developers"

Sent: Friday, January 10, 2003 5:31 AM Subject: Re: [Gimp-developer] GIMP Image Size Limits

please file a bug-report with all the information that might be useful.

Will do, as soon as I can get a few fires put out and find a few spare minutes in the day!

Regards,
Kevin M.