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Fail to open a RGBI picture (red-green-blue-infrared) as RGB pic

Forum|Forum|7 years ago
February 19, 2018
3 commentaire
2549 vue

Hi I have a Picture with RGB and infra-red Channels. But if I open this document, Photoshop recognizes a grayscale picture.

How can I open this document to see the true RGB-Colors? The infrared is not important to me.

The origin picture is from a german-government aerial photography and can be downloaded with this link:

https://www.bezreg-koeln.nrw.de/brk_internet/geobasis/luftbilderzeugnisse/digitale_orthophotos/testdaten_dop_farbe_jpeg.…

The aerial office says this is a "24 BIT - RGBI - True Color" document.

It is 15 MB big

Has anybody experience with this topic?

Ce sujet a été fermé aux réponses.

Meilleure réponse par Jeff Arola

Looks like you could do Image>Mode>Multichannel, then Image>Mode>RGB Color

D Fosse

Community Expert

nicolai - look at the Channels panel more carefully. RGB + IR is four channels, and they have solved this with a grayscale plus three alpha channels. All the information is there, but not in a standard RGB format because that only has three channels.

As Jeff says, you can go via Multichannel to RGB. This converts the three first channels into RGB, and leaves the last alpha channel as is. If this is the IR information, you can just ignore that alpha channel, or leave it for future use. You also need to check that the channel assignments are correct - that the red information is indeed in the R channel and not G or B - but if the colors look normal it is.

Incidentally, this has nothing to do with jpeg2000 as was suggested above. It's about 3 vs 4 channels.

P

PBArtattack

Inspiring

The file isn't a JPEG, it's a JPEG2000, so you're supposed to use the Open As... function. If you simply open it the usual way, it opens as an 8-bit grayscale image instead of a 16-bit color image.

Here's what's interesting, though. Apparently this file isn't compatible with Photoshop because the JP2 plugins haven't been updated in a long time while JP2 itself has continued to undergo development. Here's the message I got:

But it opens just fine in Affinity:

Unfortunately, that's the only "solution" I've got to offer you. How 'bout them apples, Adobe?

Jeff Arola

Community Expert

PBArtattack,

Is your photoshop cc 2017 updated with the latest patch?

You can see the version by going to Help>System Info and the top line is the photoshop version.

The reason i ask is here on a windows 10 machine, neither photoshop cs6 or photoshop cc 2018.1.1 generates an error, but opens the file fine.

P

PBArtattack

Inspiring

I've got CC, CC2014, CC2015, CC2015.5 and CC2017 and they're all up to date. I've also got two different plugins for JP2 (JPEG2000.8bi and j2k.8bi). No matter which version I try, if I do a plain vanilla Open, the file opens in grayscale, sometimes with a message, sometimes not. If I open it using Open As..., I get the message in my screenshot and then nothing. The mode change business does the trick, although it seems a little convoluted and definitely not intuitive.

It's funny, though, that Affinity Photo simply opens it up without any fuss — and no, I'm not pimping for Affinity. The only reason I even thought of opening it in Affinity is because of what I noticed in my file manager:

I don't know what that's about. Affinity hasn't stolen any other file associations.

A

Anonymous

Hi

Go to Image > Mode and change it from Greyscale to RGB Color

N

nicolaih85558503Auteur

Participant

Thanks for your answer! But only changing the color mode does not solve my problem? The picture is still black and white in my photoshop. But i want to bring the colors out of this document, because the download website says this is a RGB-Colored picture - like a google earth picture.

Jeff Arola

Réponse

Community Expert

Looks like you could do Image>Mode>Multichannel, then Image>Mode>RGB Color

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