ICC color management issue

[SJ9000]

Hi all,

(PhotoLine 18.90b5 - Windows)

Sometimes when I open an image PL doesn't see the embedded ICC profile ( even though it's in the EXIF data) . . .

test.jpg

and uses the default ( set in Options ) for that color space. Occasionally this is wrong. For example if I set my defualt RGB space to AdobeRGB and open an sRGB image where PL doesn't see the embedded profile it will interpret it as AdobeRGB with all the colors getting over saturated.

1) Why is PL not seeing the embedded ICC profile? Is this a bug?

2) If color management is active and you open an image that PL doesn't find an embedded ICC maybe PL could open the assign profile dialog to let the user select how to handle color for this image.

3) In a color managed workflow shouldn't every layer have an associated profile? Either explicit (from the embedded profile) or implicit (as PL is interpreting it if there's no embedded profile). So technically the ICC-Profile tag in the Document Panel should never be "None" since PL interprets everything relative to some color space. Maybe if PL is doing implicit interpretation the ICC-Profile tag could put the profile name in parenthesis, like this: ICC-Profile: (sRGB)

Any others seen this happen? If so how do you deal with it?

Thanks - Steve

[bkh]

1) Why is PL not seeing the embedded ICC profile? Is this a bug?

The EXIF ColorSpace tag isn't the same as a colour profile – there are only two standardised values, "sRGB" and "uncalibrated" (the latter often meaning Adobe RGB). PL will honour an embedded ICC profile. I'm not entirely sure why it doesn't use the ColorSpace tag, maybe because it is set in a wrong way far too often (e.g., raw files from my camera use this flag to indicate the camera JPEG setting, and fortunately PL does not interpret this as a camera profile). But maybe it would make sense to use the ColorSpace tag for camera JPEGs which don't have a real colour profile.

2) If color management is active and you open an image that PL doesn't find an embedded ICC maybe PL could open the assign profile dialog to let the user select how to handle color for this image.

Currently, PL silently uses the applicable profile set under Preferences -> Colour Management -> Standard (which should normally be sRGB). Not sure if I really want a dialogue whenever I open an image without a colour profile.

3) In a color managed workflow shouldn't every layer have an associated profile? Either explicit (from the embedded profile) or implicit (as PL is interpreting it if there's no embedded profile). So technically the ICC-Profile tag in the Document Panel should never be "None" since PL interprets everything relative to some color space. Maybe if PL is doing implicit interpretation the ICC-Profile tag could put the profile name in parenthesis, like this: ICC-Profile: (sRGB)

I don't really see the problem here. A layer without an explicit colour profile uses the profile of an enclosing group or parent layer, the document profile, or one of the standard profiles (in that order). Having a profile in parentheses probably doesn't make it clear enough that the layer/document doesn't have a proper profile, so if the general opinion is that the chosen profile should be shown, I'd prefer "None (<profile>)", or maybe just "using <profile>" in a tooltip.

Cheers

Burkhard.

[SJ9000]

Hi Burkhard,

Thanks for you responses.

Most images on the internet don't embed profiles but rely on EXIF tags for color management. I think PL should use any information it can to display the image properly. Every other ICC-aware app I've opened the above image in properly interprets it as sRGB. Only PL indicates there's no profile.

1) Why is PL not seeing the embedded ICC profile? Is this a bug?

The EXIF ColorSpace tag isn't the same as a colour profile

I know . . .

– there are only two standardised values, "sRGB" and "uncalibrated" (the latter often meaning Adobe RGB).

What does this mean, "often meaning Adobe RGB". A standard doesn't mean "often", it means always. And since there is *no* dispute about the sRGB tag shouldn't it be honored?

PL will honour an embedded ICC profile.

I know . . .

I'm not entirely sure why it doesn't use the ColorSpace tag, maybe because it is set in a wrong way far too often (e.g., raw files from my camera use this flag to indicate the camera JPEG setting, and fortunately PL does not interpret this as a camera profile). But maybe it would make sense to use the ColorSpace tag for camera JPEGs which don't have a real colour profile.

PL shouldn't ignore the tags just because they might be wrong. I'd rather see the tagged version of the image than PL's default color space version.

2) If color management is active and you open an image that PL doesn't find an embedded ICC maybe PL could open the assign profile dialog to let the user select how to handle color for this image.

Currently, PL silently uses the applicable profile set under Preferences -> Colour Management -> Standard (which should normally be sRGB).

I know . . .

Not sure if I really want a dialogue whenever I open an image without a colour profile.

In a properly color-managed workflow all elements need an associated color space.

3) In a color managed workflow shouldn't every layer have an associated profile? Either explicit (from the embedded profile) or implicit (as PL is interpreting it if there's no embedded profile). So technically the ICC-Profile tag in the Document Panel should never be "None" since PL interprets everything relative to some color space. Maybe if PL is doing implicit interpretation the ICC-Profile tag could put the profile name in parenthesis, like this: ICC-Profile: (sRGB)

I don't really see the problem here. A layer without an explicit colour profile uses the profile of an enclosing group or parent layer, the document profile, or one of the standard profiles (in that order).

Wow, that's clear as three layers of mud!

Having a profile in parentheses probably doesn't make it clear enough that the layer/document doesn't have a proper profile, so if the general opinion is that the chosen profile should be shown, I'd prefer "None (<profile>)", or maybe just "using <profile>" in a tooltip.

I disgree, it's an easy program addition, and doesn't clutter the tag with unnecessary words.

Cheers

Burkhard.

Take care

Steve

[bkh]

– there are only two standardised values, "sRGB" and "uncalibrated" (the latter often meaning Adobe RGB).

What does this mean, "often meaning Adobe RGB". A standard doesn't mean "often", it means always. And since there is *no* dispute about the sRGB tag shouldn't it be honored?

Actually, there are at least four (partially conflicting) standards to (partially) describe an image's colour space: ColorSpace tag, matrix profile in EXIF data, ICC profile, filename (first char underscore means Adobe RGB, all else is sRGB). There is no clean way of resolving this, especially since most programs only support a few of these, and not all standards cater for all needs.

Now you can effectively make PL honour the sRGB tag – just set your standard RGB profile to sRGB (which is a good choice anyway). I don't see your problem there, really.

Not sure if I really want a dialogue whenever I open an image without a colour profile.

In a properly color-managed workflow all elements need an associated color space.

Sure. The question is whether I want to set the default answer once and for all, or if I want to answer the question for each image.

Btw., you should probably try to convince the camera manufacturers to embed colour profiles. (My personal conclusion is that the only way to avoid trouble is to embed the right profile into my images right when they get imported on my computer.)

A layer without an explicit colour profile uses the profile of an enclosing group or parent layer, the document profile, or one of the standard profiles (in that order).

Wow, that's clear as three layers of mud!

Just the normal cascading of properties, as elsewhere in PL (e.g., layer intensities, scaling, …). Don't use group profiles if you find this too complicated –

I disgree, it's an easy program addition, and doesn't clutter the tag with unnecessary words.

Parentheses do not make enough of a visual difference, imo. This carries the risk that the user overlooks the important fact that the layer/document has/doesn't have a colour profile.

Cheers

Burkhard.