Mysterious color differences in .jpg images

Hi there :)

its about this thread, or more specifically the pictures posted in it:
http://ball-pythons.net/forums/showt...s-the-big-deal

the story: someone posted some pictures of orange dream combos, and i looked up orange dream combos at worldofballpythons.net . i found one if the pictures he posted, but the two versions of the same .jpg have different colors. So i posted the two pictures side by side, and others could not see the difference. but i could see a clear difference.

these are the two images in question:
http://www.worldofballpythons.com/fi...eption/001.jpg
https://sphotos-b.xx.fbcdn.net/hphot...48913769_n.jpg

do these pictures look the same to you or can you see a difference? I can certainly see it.

according to the poster of the second image, it has been produced by first sharing the picture from WOBP on facebook, and then linking directly to the shared facebook image. what REALLY confused me is that apparently some people see the difference and others dont.

so i made a screenshot about how the thread with the two pictures looked like to me:

http://img832.imageshack.us/img832/9186/awkwardreal.jpg

and now everyone could see the difference.



its a real mystery to me, could it be that facebook did something to the color balance of the image? also i know nothing about .jpg image metadata and stuff like that, can someone tell from the image when and how it has last been edited maybe? or has the file been corrupted as it got copied from server to server?

i noticed that the filesize went down from 97KB to 35.6KB. But how can compressing it mess up the color so much? Maybe a bug on facebook/instagram? And on my end, i use a fresh installation of windows 7 with updated firefox, and made and saved the screenshot with programs included in Windows 7.

i think its some kind of weird technical glitch and dont think that someone intentionally did this, but thats based on what i think about people and not based on any knowledge of the technology involved. i think it may be a bug worth reporting, the bug could be in facebook, or in instagram-technology used by facebook, or in windows 7, or in firefox.

Any ideas? The bug caused a lot of confusion in the other thread, and with the softwares involved it could be a bug affecting millions of systems and/or millions of pictures shared on facebook. But i lack the knowledge to figure it out.

I saw this first hand recently when someone posted an ivory that looked like a pastel ivory.
The yellow stripe down the back was screaming bright neon yellow, which isn't normal for an ivory.
He said the snake looked just like the picture, but I know better, no way the snake was that bright.

Interesting ...

The first two pics look the same to me but one your screen shot I see a difference for sure that's weird.

The first 2 pictures look the same to me.

But I can see the difference in your screenshot.

I have issues posting pictures sometimes. My original file looks brighter than what is uploaded to photobucket or facebook.

Sent from my DROID RAZR using Tapatalk 2

There are a huge amount of changes possible assuming no one played with either in photoshop and both are the same file. It is the colour profile the file was tagged with on upload. ICC profiles can make a huge change to colour, especially if the file is just tagged and not converted. Just tagging a incorrect profile can alter the contrast hue saturation and tonal range drastically. It looks to me however like it was helped in photoshop.

Welcome to the frustrating world of digital colour.

at least intentional photoshopping seems to be ruled out then. if it would be done intentionally, then i guess all people would see the color difference and not just me.


i guess its either some bug somewhere in my system, or facebook did it while making the file smaller.

The two links you posted fo not look the same, there is a huge difference in the color and brightness. The WOBP pic is very bright and colorful while the other looks dull and washed out. Exactly how your screen shot looks.

Looking through tapatalk they are the same. Your ss shows two different colors on the snakes.

Sent from my PG86100 using Tapatalk 2

This is a sample of incorrect ICC tagging can do,
Correct icc (sRGB-iso)
http://images61.fotki.com/v431/photo.../orion1-vi.jpgHosted on Fotki

Exact same file incorrect icc (Kodak-cine)
http://images52.fotki.com/v639/photo...ion2383-vi.jpgHosted on Fotki

To add to the issues the uploader I use force converts everything to sRGB-iso (the typical one used for images online and display as well as inkjet printed) so again a shift in colour if it mis-matches. It is most likely this is what the issue is.

Quote:

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Originally Posted by Kurtilein

at least intentional photoshopping seems to be ruled out then. if it would be done intentionally, then i guess all people would see the color difference and not just me.


i guess its either some bug somewhere in my system, or facebook did it while making the file smaller.

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I saw the colour differences on the thread yet, when checking the original hosting of the images both appear identical and oddly enough they seem to both be the one I would expect to the the shopped version with higher saturation.