Re: [Gimp-user] Color Management Woes

2010-01-17 Thread Frank Gore
So I moved upstream and asked about this on the LittleCMS mailing
list. From what the users and devs there were able to figure out,
there is no ICC profile embedded in my camera's JPG and TIF files. In
fact, DSLR cameras do not embed an ICC profile at all. The Digital
Camera File system (DCF) specification explicitly states that color
profile information should be specified as part of the EXIF metadata.
There's a whole series of tags in a digital camera's file which
defines which colorspace should be used to interpret it. It's not just
ColorSpace, but others as well all taken together.

So again, this goes back to the application level, and not the color
management library. If the application (in this case Gimp) was
properly DCF-aware, then it would detect the proper color profile
that's specified in the image file.

So... is this the right mailing list for this discussion, or do I need
to subscribe to the Dev mailing list?

Here are the relevant emails from the LittleCMS mailing list.

On Sun, Jan 17, 2010 at 7:32 AM, Larry Reeve la...@polybytes.com wrote:
 The first image is in DCF Colorspace. This can be seen from the following
 entries in the EXIF:

 Color Space:Uncalibrated
 WhitePoint X:   0.31
 WhitePoint Y:   0.33
 Chromaticity Red(X):0.64
 Chromaticity Red(Y):0.33
 Chromaticity Green(X):  0.21
 Chromaticity Green(Y):  0.71
 Chromaticity Blue(X):   0.15
 Chromaticity Blue(Y):   0.06
 YCbCrCoefficient 1: 0.30
 YCbCrCoefficient 2: 0.59
 YCbCrCoefficient 3: 0.11

 A DCF aware application sees this information and processes the image
 accordingly (which means use an Adobe RGB profile).

On Sun, Jan 17, 2010 at 5:03 PM, Larry Reeve la...@polybytes.com wrote:
 LCMS does not have anything to do with the color space defined in the EXIF
 block of a JPEG file. There is no embedded profile. It is up to the
 application using LCMS to evaluate the color space definitions in the EXIF
 and take the action to load and use an Adobe RGB profile if it is needed.
 The DCF Optional Color Space (see paragraph 6.2 of of JEITA CP-3461 Design
 rule for Camera File system DCF Version 2.0) defines the values that should
 alert an application to take this action:

 Color Space:Uncalibrated
 WhitePoint X:   0.31
 WhitePoint Y:   0.33
 Chromaticity Red(X):0.64
 Chromaticity Red(Y):0.33
 Chromaticity Green(X):  0.21
 Chromaticity Green(Y):  0.71
 Chromaticity Blue(X):   0.15
 Chromaticity Blue(Y):   0.06
 YCbCrCoefficient 1: 0.30
 YCbCrCoefficient 2: 0.59
 YCbCrCoefficient 3: 0.11

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Project Manager
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Re: [Gimp-user] Color Management Woes

2010-01-17 Thread Frank Gore
HAH! All of this has been a long-standing bug:

https://bugzilla.gnome.org/show_bug.cgi?id=492048

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Re: [Gimp-user] Color Management Woes

2010-01-16 Thread Milan Knížek
Frank Gore píše v Pá 15. 01. 2010 v 17:12 -0500:
 But this begs the question, what does Gimp use to determine the
 embedded color profile? The EXIF data, or something else? Because even
 if I change that tag from Uncalibrated to Adobe RGB, it still
 doesn't change how Gimp treats it.
 
Again, you are mixing two different things:

embedded profile means that there is an actual binary data inside of
JPEG. This can be extracted to a profile.icc if needed.

Color Space tag (either standard exif or some proprietary maker note)
just says that the image data is in some standard colour space (sRGB,
AdobeRGB), but the profile itself is not embedded and the program must
supply it on its own.

Use of tags instead of embedding profile is an advantage: the image file
is a bit smaller.

I would assume that GIMP does not care about tags, just looks for any
embedded profile. But the developers would have to confirm it.

regards,

Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)

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Re: [Gimp-user] Color Management Woes

2010-01-16 Thread Frank Gore
On Sat, Jan 16, 2010 at 3:32 AM, Milan Knížek knizek.co...@volny.cz wrote:
 I would assume that GIMP does not care about tags, just looks for any
 embedded profile. But the developers would have to confirm it.

Upon further research, I just noticed there are two major versions of
the ICC specification, 2.x and 4.x. Does Gimp support both? Does it
support the latest? (4.2)

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Re: [Gimp-user] Color Management Woes

2010-01-16 Thread Alexandre Prokoudine
On 1/16/10, Frank Gore wrote:

 Upon further research, I just noticed there are two major versions of
 the ICC specification, 2.x and 4.x. Does Gimp support both? Does it
 support the latest? (4.2)

Upon even further research you would find out that GIMP doesn't care
about that, because this is what GIMP uses LittleCMS library for :)
Which coincidentally supports both 2.x and 4.x. Not 4.2, perhaps, but
chances that anyone has v4.2 profiles around are floating around 0.

Alexandre
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Re: [Gimp-user] Color Management Woes

2010-01-15 Thread Milan Knížek
Frank Gore píše v Čt 14. 01. 2010 v 21:35 -0500:

 Sorry, those were links to the version of the pictures as displayed by
 Picasa, which has the metadata stripped. The direct download links are
 as follows:
 
I thought your camera would be very unusual to provide JPEGs w/o
metadata...
 Adobe RGB:
 http://lh6.ggpht.com/_HAZjMzZWrtc/S05qkb7KkYI/BCw/oPJ80XXYH-Y/d/_GOR3359.JPG
 
$ exiftool -a -G -H _GOR3359.JPG | grep Color
[File]   - Color Components: 3
[EXIF]  0xa001 Color Space : Uncalibrated
[MakerNotes]0x0037 Color Space : Adobe RGB

$ exiv2 -pa _GOR3359.JPG | grep Color
Exif.Pentax.ColorSpace   Short   1  Adobe RGB
Exif.Pentax.ColorTemperature Short   1  0
Exif.Pentax.ColorInfoUndefined  18  32 131 31
100 31 125 32 156 33 72 32 246 31 51 31 10 0 0 
Exif.Photo.ColorSpaceShort   1  Uncalibrated

 As I stated in my original post, the sRGB image has the EXIF tag
 Color space set as sRGB. The Adobe RGB picture has that same EXIF
 tag set as Uncalibrated. That's how it comes right out of the
 camera. Changing it to Adobe RGB does not change anything. Gimp
 still doesn't detect the color space properly and still assumes it's
 sRGB.
Here you talk about Exif.ColourSpace. The info above is included in the
blob of nonstandard metadata of Pentax... They do in on purpose, since
the standard for Exif does not allow AdobeRGB:

While the EXIF header in your images does have a field called color
space, use of this data is very limited because the only two values
allowed in the EXIF color space field are (1) sRGB and (2) unspecified.

Anyway, it would be good if graphics programs try to identify also the
known maker notes to find out the colour space.

Regards,

Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)

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Re: [Gimp-user] Color Management Woes

2010-01-15 Thread Milan Knížek
Frank Gore píše v St 13. 01. 2010 v 18:20 -0500:
 
 In any case, like I mentioned in my original post, I specifically have
 it set to Ask what to do in the Preferences, and it doesn't ask.
 
I agree with you, it is definitely a bug. GIMP should not assume that
JPEG is in sRGB colour space when exif header says Uncalibrated.

regards,

Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)

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Re: [Gimp-user] Color Management Woes

2010-01-14 Thread David Gowers
On Thu, Jan 14, 2010 at 4:18 PM, Frank Gore g...@projectpontiac.com wrote:
 On Wed, Jan 13, 2010 at 11:43 PM, David Gowers 00a...@gmail.com wrote:
 We don't know if their formats are crazy.
 But they certainly appear to be undocumented. Until they are
 documented, or someone reverse-engineers them, we are unlikely to gain
 support for them in open-source software.

 (OTOH, it could just be attached in the metadata. EXIF / IPTC support
 is not complete yet.)

 ok... but why is Gimp assuming sRGB? Even if the color profile is
 attached in some bizarre non-standard manner, Gimp should detect NO
 color profile and ask me about it when I open the file. Isn't that how
 it's supposed to work? That's what other applications do, for example
 Digikam/showFoto.

Don't you think that would be very tiresome?
Most images have no ICC profile attached; in this case, sRGB is indeed
implied. Producing images that are not sRGB but have no ICC profile
attached is wrong (more precisely, it's a miscommunication, saying
that the image is sRGB when it's not. ).
I appreciate your situation of needing to correct the profile here,
OTOH, have you considered using tools like imagemagick and jpegicc to
detect the camera it came from and then attach an appropriate profile.
this would allow you to assign profiles automatically in large
batches. IMO this is much less painful all around.

BTW, I just checked the exif information on those JPEGs and both have
no EXIF information. So it does look indeed like the profile data is
stored in some custom format; there may even be no profile per se
stored, just a reference to or description of one.
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Re: [Gimp-user] Color Management Woes

2010-01-14 Thread Milan Knížek
David Gowers píše v Čt 14. 01. 2010 v 18:56 +1030:
 On Thu, Jan 14, 2010 at 4:18 PM, Frank Gore g...@projectpontiac.com wrote:
  color profile and ask me about it when I open the file. Isn't that how
  it's supposed to work? That's what other applications do, for example
  Digikam/showFoto.
 
In digiKam, the user can pre-set what to do in case of a missing
profile. Majority would probably use assign sRGB instead of asking
each time.
 BTW, I just checked the exif information on those JPEGs and both have
 no EXIF information. So it does look indeed like the profile data is
 stored in some custom format; there may even be no profile per se
 stored, just a reference to or description of one.
How about the filenames? AdobeRGB image starts with _ (underscore).

As far as I can tell, ImageMagick, exiv2 and exiftool do not report any
metadata, even not the maker's non-readable ones.

Regards,

Milan Knizek
knizek (dot) confy (at) volny (dot) cz
http://www.milan-knizek.net - About linux and photography (Czech
language only)

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[Gimp-user] Color Management Woes

2010-01-14 Thread Frank Gore
On Thu, Jan 14, 2010 at 3:26 AM, David Gowers 00a...@gmail.com wrote:
 Don't you think that would be very tiresome?
 Most images have no ICC profile attached; in this case, sRGB is indeed
 implied. Producing images that are not sRGB but have no ICC profile
 attached is wrong (more precisely, it's a miscommunication, saying
 that the image is sRGB when it's not. ).

Nope, I wouldn't find that tiresome at all. Many other applications
have an option to allow just that. When I edit a file in Digikam, I
have it set so that if there's no color profile detected, it asks me
what the source color profile should be and whether or not to convert
it to my default working space. This is neither tiresome nor annoying.
If I did find it tiresome, I could just turn that off and have it use
a default profile (like sRGB) for the source file when none is
detected. As far as I'm concerned, this is just part of having proper
color management in my workflow.

 I appreciate your situation of needing to correct the profile here,
 OTOH, have you considered using tools like imagemagick and jpegicc to
 detect the camera it came from and then attach an appropriate profile.
 this would allow you to assign profiles automatically in large
 batches. IMO this is much less painful all around.

That would add a bunch more steps to my workflow, and it would only
work on this computer. I frequently have to work on other people's
computers with files straight from the camera (and other people's
cameras), and Gimp is the only cross-platform tool I have that does
what I need.

 BTW, I just checked the exif information on those JPEGs and both have
 no EXIF information. So it does look indeed like the profile data is
 stored in some custom format; there may even be no profile per se
 stored, just a reference to or description of one.

Sorry, those were links to the version of the pictures as displayed by
Picasa, which has the metadata stripped. The direct download links are
as follows:

Adobe RGB:
http://lh6.ggpht.com/_HAZjMzZWrtc/S05qkb7KkYI/BCw/oPJ80XXYH-Y/d/_GOR3359.JPG

sRGB:
http://lh3.ggpht.com/_HAZjMzZWrtc/S05qk1yxBOI/BC0/5kXGfiIIF7s/d/GORE3360.JPG

There's a LOT of metadata, Pentax fills in more metadata than I thought existed.

On Thu, Jan 14, 2010 at 2:56 PM, Milan Knížek knizek.co...@volny.cz wrote:
 How about the filenames? AdobeRGB image starts with _ (underscore).

Yes, the link to the Adobe RGB file I posted is named _GOR3359.JPG and
the sRGB one is named GORE3360.JPG

As I stated in my original post, the sRGB image has the EXIF tag
Color space set as sRGB. The Adobe RGB picture has that same EXIF
tag set as Uncalibrated. That's how it comes right out of the
camera. Changing it to Adobe RGB does not change anything. Gimp
still doesn't detect the color space properly and still assumes it's
sRGB.
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Re: [Gimp-user] Color Management Woes

2010-01-14 Thread Tom Williams
Frank Gore wrote:
 Sorry, those were links to the version of the pictures as displayed by
 Picasa, which has the metadata stripped. The direct download links are
 as follows:

 Adobe RGB:
 http://lh6.ggpht.com/_HAZjMzZWrtc/S05qkb7KkYI/BCw/oPJ80XXYH-Y/d/_GOR3359.JPG

 sRGB:
 http://lh3.ggpht.com/_HAZjMzZWrtc/S05qk1yxBOI/BC0/5kXGfiIIF7s/d/GORE3360.JPG

 There's a LOT of metadata, Pentax fills in more metadata than I thought 
 existed.
   
When I open the Adobe RGB image in GIMP 2.6.7 on Ubuntu 9.10 Linux
(64-bit), the EXIF browser shows the ColorSpace as:

Internal error (unknown value 65535)


Peace...

Tom
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[Gimp-user] Color Management Woes

2010-01-13 Thread Frank Gore
I've been pulling my hair out trying to figure out color management in Gimp.

In the preferences, I clearly have File Open Behaviour set to Ask
what to do. My working profile is sRGB, and so is my Monitor profile.
I have Display rendering intent set to Relative colorimetric. Yet,
everytime I open an image, Gimp never asks me what to do about the
color profile. It always assumes sRGB, even if the embedded color
profile is Adobe RGB or ProPhoto or whatever else. I always have to
manually assign the right color profile after the file has been
opened.

Further, when I go to assign a color profile, I have to know in
advance what the profile of that image was. Gimp doesn't tell me. It
lets me change to whatever profile I want, but it won't let me know
which one is embedded in the image. Sometimes, the color profile is
not listed in the EXIF data at all, which makes it harder to guess.
For example, when my camera is set to Adobe RGB, it leaves the EXIF
Color space field set to Unassigned.

Is this normal Gimp behavior? It's making color management a real
nightmare and giving me all kinds of headaches. I sometimes receive
images in many different color spaces and I don't always know which
ones. Some people love working in ProPhoto because it makes them feel
all 1337 and superior. Others send me stuff in Adobe RGB because
that's what their printing company requires. I try to stick to sRGB
whenever possible, but it's not always ideal.

I hope someone can help me with this issue.

I have Gimp 2.6.8 on openSUSE 11.2 x86_64. It's a backport from the
Gnome OBS repository.

-- 
Frank Gore
Project Manager
www.projectpontiac.com
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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread Michael J. Hammel
On Wed, 2010-01-13 at 17:46 -0500, Frank Gore wrote:
 In the preferences, I clearly have File Open Behaviour set to Ask
 what to do. My working profile is sRGB, and so is my Monitor profile.

I'm no expert about this so my wild-ass guess is that it doesn't ask
because there is nothing to do.  Consider that the working profile is
what a file *HAS* to be converted to or else you can't open it.  If the
file has an Adobe RGB profile but there is no such working profile the
file couldn't be edited unless it was automatically converted, right?

So the conversion would be to your Monitor profile.  If you had a
monitor profile different than the working profile then the Adobe RGB
would have to converted to the monitor profile first and then to the
working profile to be edited.  Since the monitor profile and working
profile are the same then there is nothing to ask - you simply get an
automatic conversion to sRGB.

But again, that's just a wild guess.  I've never dug into that part of
the code to know what's really going on.  Hopefully Sven or one of the
developers will correct me here.
-- 
Michael J. HammelPrincipal Software Engineer
mjham...@graphics-muse.org   http://graphics-muse.org
--
Stupidity:  Quitters never win.  Winners never quit.  But those who never
win and never quit are idiots.

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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread David Gowers
On Thu, Jan 14, 2010 at 9:16 AM, Frank Gore g...@projectpontiac.com wrote:
 I've been pulling my hair out trying to figure out color management in Gimp.

 In the preferences, I clearly have File Open Behaviour set to Ask
 what to do. My working profile is sRGB, and so is my Monitor profile.
 I have Display rendering intent set to Relative colorimetric. Yet,
 everytime I open an image, Gimp never asks me what to do about the
 color profile. It always assumes sRGB, even if the embedded color
 profile is Adobe RGB or ProPhoto or whatever else. I always have to
 manually assign the right color profile after the file has been
 opened.

 Further, when I go to assign a color profile, I have to know in
 advance what the profile of that image was. Gimp doesn't tell me. It
 lets me change to whatever profile I want, but it won't let me know
 which one is embedded in the image.
Also.. does that mean that you go to the 'Color profile' section of
Image Properties and it says nothing / is blank?
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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread Frank Gore
On Wed, Jan 13, 2010 at 6:21 PM, David Gowers 00a...@gmail.com wrote:
 That sounds very much like it is attached in a non-standard way.

Actually, you're entirely right. If I assign an Adobe RGB profile to
the picture, then save it, and re-open it, THEN it asks me what to do
with the color profile, just like I expected it to. Apparently the
original file has the profile embedded in some different manner.
However, [big-brand commercial application] has no trouble determining
what the color space should be, even with the original files.

On Wed, Jan 13, 2010 at 6:23 PM, David Gowers 00a...@gmail.com wrote:
 Also.. does that mean that you go to the 'Color profile' section of
 Image Properties and it says nothing / is blank?

Nope, it says it's sRGB. Regardless of what it SHOULD be, it always
says sRGB (until I assign a different color space manually). This is
wrong.

The files I'm working with right now are from my Pentax K-7 DSLR. The
JPG and TIF files it produces apparently have the color profile
embedded in a weird way, thereby keeping Gimp from seeing it. Now I
don't know how weird it is, since every commercial application I've
used has had no problems with it so far. It's only Gimp and Digikam
that are giving me trouble.

-- 
Frank Gore
Project Manager
www.projectpontiac.com
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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread Michael J. Hammel
On Wed, 2010-01-13 at 18:20 -0500, Frank Gore wrote:
 But the problem is that it doesn't convert when I open the file. It
 just assumes the picture is in sRGB and interprets the color space
 that way. Have you ever seen the colors of a file in Adobe RGB that's
 incorrectly interpreted as sRGB? They're flat and dull, bland,
 lifeless. I lose a bunch of contrast and saturation.

Possibly, but then you don't provide a display color profile so maybe
it's your display that's washed out, not the image.  What may happen is
that the Adobe RGB-sRGB happens just fine but what you *SEE* is the
sRGB, not what the image should be when mapped to the color profile of
the monitor.

Again, I'm mostly talking out my be-hind here.  I've done some articles
on the color management stuff so I've played with it and I have both
monitor and print profiles set up.  But I'm not completely sure where
the conversions happen on the file open and display pipeline.

 Oh I can assign the right color profile and it fixes it right away, no
 conversion necessary. But how do I know which color profile to assign?
 What if the original was SUPPOSED to look bland and lifeless? What if
 I'm messing up the colors by assigning an Adobe RGB profile where I
 was supposed to leave it as sRGB? That tends to mess up the colors the
 other way, adding contrast and saturation where there should be less.

Again, this seems to me to point to an incorrect monitor color
profile.  

 In any case, like I mentioned in my original post, I specifically have
 it set to Ask what to do in the Preferences, and it doesn't ask.

Like I said, this could be because there is nothing to ask about.  The
file is opened by converting from its original color space to the
working space and then displayed that way.  The asking may only happen
when you want to convert from the original color space to your display
color space (which could be your monitor profile or a print profile, for
example) before conversion to sRGB for working.

Again, this just a guess.  I'm talking enough to convince myself but we
really need someone with more color management experience explaining it.
-- 
Michael J. HammelPrincipal Software Engineer
mjham...@graphics-muse.org   http://graphics-muse.org
--
Don't let a little dispute injure a great friendship.
  --  Credited to the Dalai Lama.

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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread Michael J. Hammel
On Wed, 2010-01-13 at 18:34 -0500, Frank Gore wrote:
 On Wed, Jan 13, 2010 at 6:21 PM, David Gowers 00a...@gmail.com wrote:
  That sounds very much like it is attached in a non-standard way.
 
 Actually, you're entirely right. If I assign an Adobe RGB profile to
 the picture, then save it, and re-open it, THEN it asks me what to do
 with the color profile, just like I expected it to. Apparently the
 original file has the profile embedded in some different manner.
 However, [big-brand commercial application] has no trouble determining
 what the color space should be, even with the original files.

Ah.  See?  I told you we needed someone who understood it better.  :-)
-- 
Michael J. HammelPrincipal Software Engineer
mjham...@graphics-muse.org   http://graphics-muse.org
--
Don't let a little dispute injure a great friendship.
  --  Credited to the Dalai Lama.

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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread Frank Gore
On Wed, Jan 13, 2010 at 7:36 PM, Frank Gore g...@projectpontiac.com wrote:
 As I mentioned, all the commercial applications I've tried had no
 problems determining the appropriate color space for these files. It's
 only open source tools that are unable to, including Gimp.

 So is this a bug? Or is Pentax really that crazy with their file
 formats? They can't be that crazy if commercial applications have no
 trouble with the files.

Someone mentioned I should perhaps post examples of these files, and
that's a fine idea. Wish I'd thought of it sooner. These were taken at
seriously-reduced megapixels in the interest of file size. I figured
the file format was more important than the quality of the picture.

Here's one straight from my K-7, in Adobe RGB:
http://picasaweb.google.ca/lh/photo/Wc8Lq42A20qRxDoTj1dNRQ?feat=directlink

And here's another one in sRGB, taken immediately after the above:
http://picasaweb.google.ca/lh/photo/c7_78WNLRXvEgHnmb6QM4g?feat=directlink

Both can be downloaded in full by using the Download link

-- 
Frank Gore
Project Manager
www.projectpontiac.com
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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread David Gowers
On Thu, Jan 14, 2010 at 11:25 AM, Frank Gore g...@projectpontiac.com wrote:
 On Wed, Jan 13, 2010 at 7:36 PM, Frank Gore g...@projectpontiac.com wrote:
 As I mentioned, all the commercial applications I've tried had no
 problems determining the appropriate color space for these files. It's
 only open source tools that are unable to, including Gimp.

 So is this a bug? Or is Pentax really that crazy with their file
 formats? They can't be that crazy if commercial applications have no
 trouble with the files.
That's a fallacy, I'm afraid.

We don't know if their formats are crazy.
But they certainly appear to be undocumented. Until they are
documented, or someone reverse-engineers them, we are unlikely to gain
support for them in open-source software.

(OTOH, it could just be attached in the metadata. EXIF / IPTC support
is not complete yet.)


 Someone mentioned I should perhaps post examples of these files, and
 that's a fine idea. Wish I'd thought of it sooner. These were taken at
 seriously-reduced megapixels in the interest of file size. I figured
 the file format was more important than the quality of the picture.


 Here's one straight from my K-7, in Adobe RGB:
 http://picasaweb.google.ca/lh/photo/Wc8Lq42A20qRxDoTj1dNRQ?feat=directlink

 And here's another one in sRGB, taken immediately after the above:
 http://picasaweb.google.ca/lh/photo/c7_78WNLRXvEgHnmb6QM4g?feat=directlink

These could be quite helpful if someone is inclined to reverse
engineer it to spot the difference
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Re: [Gimp-user] Color Management Woes

2010-01-13 Thread Frank Gore
On Wed, Jan 13, 2010 at 11:43 PM, David Gowers 00a...@gmail.com wrote:
 We don't know if their formats are crazy.
 But they certainly appear to be undocumented. Until they are
 documented, or someone reverse-engineers them, we are unlikely to gain
 support for them in open-source software.

 (OTOH, it could just be attached in the metadata. EXIF / IPTC support
 is not complete yet.)

ok... but why is Gimp assuming sRGB? Even if the color profile is
attached in some bizarre non-standard manner, Gimp should detect NO
color profile and ask me about it when I open the file. Isn't that how
it's supposed to work? That's what other applications do, for example
Digikam/showFoto.

-- 
Frank Gore
Project Manager
www.projectpontiac.com
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