Bugs v1.91.1: JPG Gamma?

[cooper2007]

Hi there,

just noticed that the colors of JPG's displayed in XnView are different from other programs. Black is too dark, red too red, yellow to strong. Camera was a Canon EOS-1Ds Mark II, so I believe the JPG should have better colors.... which are shown by MS Paint (XP), MS Office Picture Manager and Picture&Fax-Display (don't know the english name).
Since the status line states obviously the gamma value 0.69 next to size (can't think of anything else, 1063x1540x24, 0.69), why is XnView displaying not displaying image's natural colors? Or is XnView displaying it's natural colors, and M$'s programs are not?
EXIF data shows that the JPG was saved with Adobe Photshop 7.0, but only modified in size.
I love XnView for a long time, but this issue is kind of annoying.

[xnview]

Hi there,

just noticed that the colors of JPG's displayed in XnView are different from other programs. Black is too dark, red too red, yellow to strong. Camera was a Canon EOS-1Ds Mark II, so I believe the JPG should have better colors.... which are shown by MS Paint (XP), MS Office Picture Manager and Picture&Fax-Display (don't know the english name).
Since the status line states obviously the gamma value 0.69 next to size (can't think of anything else, 1063x1540x24, 0.69), why is XnView displaying not displaying image's natural colors? Or is XnView displaying it's natural colors, and M$'s programs are not?
EXIF data shows that the JPG was saved with Adobe Photshop 7.0, but only modified in size.
I love XnView for a long time, but this issue is kind of annoying.

Could you post a sample?

[cooper2007]

Hi there,

just noticed that the colors of JPG's displayed in XnView are different from other programs. Black is too dark, red too red, yellow to strong. Camera was a Canon EOS-1Ds Mark II, so I believe the JPG should have better colors.... which are shown by MS Paint (XP), MS Office Picture Manager and Picture&Fax-Display (don't know the english name).
Since the status line states obviously the gamma value 0.69 next to size (can't think of anything else, 1063x1540x24, 0.69), why is XnView displaying not displaying image's natural colors? Or is XnView displaying it's natural colors, and M$'s programs are not?
EXIF data shows that the JPG was saved with Adobe Photshop 7.0, but only modified in size.
I love XnView for a long time, but this issue is kind of annoying.

Could you post a sample?

http://files.to/get/469704/12004/xnv-v1911.bmp

[Drahken]

Pierre- Is that 0.69 thing in the status bar the gamma? If so, where is such info stored in a JPG? I have some that say 0.65 and 0.66 in the status bar, but there's nothing in the EXIF not ITPC data that corresponds.


Cooper- Are all images darker in xnview, or only JPGs, or only photos taken with that camera, or....? If it's all images, then you probably have the gamma setting in xnview's options set low.


Edit: Cooper- I think pierre wanted one of the actual JPGs as a sample, so he could test it himself and try to find the problem.

[Guest]

Pierre- Is that 0.69 thing in the status bar the gamma? If so, where is such info stored in a JPG? I have some that say 0.65 and 0.66 in the status bar, but there's nothing in the EXIF not ITPC data that corresponds.


Cooper- Are all images darker in xnview, or only JPGs, or only photos taken with that camera, or....? If it's all images, then you probably have the gamma setting in xnview's options set low.


Edit: Cooper- I think pierre wanted one of the actual JPGs as a sample, so he could test it himself and try to find the problem.

The darkness seems to depend on value in status bar. As I can't post the original image, here is another one:
http://files.to/get/469744/23342/D043.JPG[img]
Gamma (?) is 1.33, another camera. Orange looks brighter in XnView, darker in MS Paint.
I only can modify gamma in preview... and it's off.

It seems similar in PNG's! A PNG with Gamma 1.28 looks darker in MS Paint as well!

Thanks,
Cooper2007[/img]

[xnview]

Pierre- Is that 0.69 thing in the status bar the gamma? If so, where is such info stored in a JPG? I have some that say 0.65 and 0.66 in the status bar, but there's nothing in the EXIF not ITPC data that corresponds.
.

No this value is the ratio

[Drahken]

Gamma (?) is 1.33, another camera. Orange looks brighter in XnView, darker in MS Paint.
I only can modify gamma in preview... and it's off.

It seems similar in PNG's! A PNG with Gamma 1.28 looks darker in MS Paint as well!

Well there's your problem right there![/overused quote]
Xnview is showing the images correctly, according to the gamma data. Gamma=1.00 means no adjustment, gamma=0.99 or less means make the image darker, gamma=1.01 or more means make the image lighter. Any prog that shows the 1.33 and 1.28 gamma images lighter than other progs is displaying them correctly, and any prog that shows the 0.69 image darker than other progs is showing it correctly. The other progs are ignoring the gamma adjustment.

[xnview]

I have no problem with your picture, the same view with IE, firefox, XnView, ACDsee, and other software...

[Drahken]

No noticeable difference here either.

[XnTriq]

just noticed that the colors of JPG's displayed in XnView are different from other programs. Black is too dark, red too red, yellow to strong. Camera was a Canon EOS-1Ds Mark II, so I believe the JPG should have better colors.... which are shown by MS Paint (XP), MS Office Picture Manager and Picture&Fax-Display (don't know the english name).

It's gotta be a color management issue.

I've made a few screenshots on my system (Windows 2000, from left to right):

1. XnView 1.91 (Use ICC Embedded Profile activated)
2. Paint Shop Pro 9.01 (not color-managed)
3. Photoshop 6.0.1 (Color Management Off)

• 
  [ Zoom ]

• Digital Photography Review: Canon EOS-1Ds
  • Features » Color Matrix
  • Software » Output samples
  • Conclusion » Cons
    “JPEG files are not tagged with color profile when Adobe RGB color matrix is selected”
• Canon ICC Profiles Guide
  • James Stephens: Download – Canon ICC Profiles Guide
  • Photography-on-the.net » Canon Digital Photography Forums: Canon ICC Profile Guide – Something New for Canon Printers
  • EOS Digital Photographer's Resource News: Color managment techniques, tips and tricks
• Adam Tow: EOS-1D Firmware and JPEG's – An investigation into the JPEG format of EOS-1D images
  “The Canon EOS-1D firmware creates non-standard JPEG/JFIF files.”

[Cooper2007]

just noticed that the colors of JPG's displayed in XnView are different from other programs. Black is too dark, red too red, yellow to strong. Camera was a Canon EOS-1Ds Mark II, so I believe the JPG should have better colors.... which are shown by MS Paint (XP), MS Office Picture Manager and Picture&Fax-Display (don't know the english name).

It's gotta be a color management issue.

I've made a few screenshots on my system (Windows 2000, from left to right):

1. XnView 1.91 (Use ICC Embedded Profile activated)
2. Paint Shop Pro 9.01 (not color-managed)
3. Photoshop 6.0.1 (Color Management Off)

Thanks XnTriq for the comparison. The firmware of the 1D should be fine...
So, what's the conclusion? 0.69 is not the gamma, but the ratio. Thanks, Pierre.
Colormanagment is still tricky. But on which prog can I rely on? ICC profile was off and does not show a difference. So, there is no switch in XnView to disable this colormanagement, which could make JPG's and PNG's look the same (i.e. more neutral colors). But even with colormagement off PSP and PS look different (XnTriqs image)!
I still feel that the colors of XnView are too different, at least here on my XP. I do not think that the Canon 1D makes these artificial colors.
Why is no one else having this issue? Where is the truth?
Slightly going mad...

[XnTriq]

Errata regarding my last post:

1. I hadn't noticed Cooper2007's remark that the sample photo wasn't taken with a Canon EOS-1Ds but with “another camera” (Konica Minolta DiMAGE A200). Therefore, any speculation that we're dealing with a problem which could be specific to one particular camera model is futile.
2. I had forgotten that Paint Shop Pro's monitor gamma had been set to 1.25. That explains why one of the screenshots came out brighter.

Today I've made a new series of screenshots. In order to get an objective assessment I cropped all of them to the same area, saved them to BMP format and compared the resulting files with Bindiff.

Some progams display D043.JPG identically, ...

• XnView 1.91.1
• Corel Photo-Paint 11 SP2
• Macromedia Fireworks 2.0.2
• I****View 4.00
• Microsoft Internet Explorer 6 SP1
• Mozilla Firefox 2.0.0.4

... while others don't.

• Adobe Photoshop 6.0.1
• iGrafx Image 1.0.1 (Micrografx Picture Publisher 9)
• Jasc Paint Shop Pro 9.01
• Cerious ThumbsPlus 7.0 SP1

The differences are very subtle. In fact, on my uncalibrated (and ailing) CRT monitor I can't spot any.

So we're back to square one.

@ Cooper2007:

1. Did you compare the screen output of Microsoft's graphics programs (Paint, Picture & Fax Viewer, Office Picture Manager) to that of non-MS software (other than XnView)?
2. Is Microsoft's Color Control Panel Applet for Windows XP installed on your system?

[Cooper2007]

Errata regarding my last post:

1. I hadn't noticed Cooper2007's remark that the sample photo wasn't taken with a Canon EOS-1Ds but with “another camera” (Konica Minolta DiMAGE A200). Therefore, any speculation that we're dealing with a problem which could be specific to one particular camera model is futile.
2. I had forgotten that Paint Shop Pro's monitor gamma had been set to 1.25. That explains why one of the screenshots came out brighter.

Today I've made a new series of screenshots. In order to get an objective assessment I cropped all of them to the same area, saved them to BMP format and compared the resulting files with Bindiff.

Some progams display D043.JPG identically, ...

• XnView 1.91.1
• Corel Photo-Paint 11 SP2
• Macromedia Fireworks 2.0.2
• I****View 4.00
• Microsoft Internet Explorer 6 SP1
• Mozilla Firefox 2.0.0.4

... while others don't.

• Adobe Photoshop 6.0.1
• iGrafx Image 1.0.1 (Micrografx Picture Publisher 9)
• Jasc Paint Shop Pro 9.01
• Cerious ThumbsPlus 7.0 SP1

The differences are very subtle. In fact, on my uncalibrated (and ailing) CRT monitor I can't spot any.

So we're back to square one.

@ Cooper2007:

1. Did you compare the screen output of Microsoft's graphics programs (Paint, Picture & Fax Viewer, Office Picture Manager) to that of non-MS software (other than XnView)?
2. Is Microsoft's Color Control Panel Applet for Windows XP installed on your system?

Thanks for your investigations, XnTriq!
BTW, while thinking about which of my programs could display JPG, I found that FF 2.0.0.4 could not display the first photo (FF states is contains errors!) So, that's very interesting, since it was saved with PhotoShop 7.0...
CorelDraw 11 (awful prog) is displaying it also different (not as XnView, not as M$ progs).
It's a pity that I can't post that first photo.

ad 1. No, I could boot Linux, but did not yet try.
ad 2. No.

[XnTriq]

BTW, while thinking about which of my programs could display JPG, I found that FF 2.0.0.4 could not display the first photo (FF states is contains errors!) So, that's very interesting, since it was saved with PhotoShop 7.0...

This could be an indicator that the file was saved in CMYK color space (instead of RGB).

CorelDraw 11 (awful prog) is displaying it also different (not as XnView, not as M$ progs).

What are your settings in CorelDraw & Photo-Paint (Tools » Color Management » Style)?

• CorelDRAW Community Forums: .jpg changes .cpt colors - How to fix this?

It's a pity that I can't post that first photo.

I assume that's due to privacy reasons. But maybe you could post the technical specs of the file as provided by the following utilities:

• JPEGsnoop – JPEG File Decoding Utility
  
  [ Zoom ]
• jpegdump – Dump JPEG marker information
  
  [ Zoom ]

[Cooper2007]

Link for JPEGsnoop output: http://files.to/get/472574/51633/06.06.07--001.jpg.txt
It was saved in CMYK, as XnView tells correctly. JPEGsnoop states lots of errors.
When I switch off CM inCorel Draw 11, it looks very much like XnView displayed it first (before update to 1.91.1?)...
No, I'm not very much into details of CM concerns, but I thought JPG is JPG and CM is kind of transparent. So I think this is not an issue of XnView and therefore not a bug.

TNX XnTriq, TNX Pierre!
PS: Sorry, no full quotes, got spam classification.