Christopher,

that depends on the profiles and settings. In most real world scenarios, they 
are not. Usually, especially when using 8bit per channel (in contrast to for 
example unbound floating point) it's not reversible without a certain loss of 
information due to integer math and gamut clipping. If you convert an image 
from one profile to the other, one of the profiles will likely have a smaller 
gamut, so you lose either "color range" or "color accuracy", otherwise the 
profiles would be identical or don't make much sense in color management (for 
example, exchanging channels or reversing).

Back to you example - you might likely end up with something like:
"Original image" (= RGB value in input color space) -> 224,122,50
"Transformed Image" (= 'closest match' RGB value in destination color space) -> 
255, 110,80
transformed back to original color space: (= 'closest match' RGB value to that 
in input color space) -> 212, 123, 48
Also, it rarely makes sense to transform images force and back.

Excuse me for being so direct, I hope you don't take this as offence, but your 
questions seem to be "extremely basic" and not so much related to the 
implementation or usage of littleCMS, but touching very basics of color 
management in general, don't you think a basic training in color management 
might be a good idea before trying to use a library to implement a color 
managed application?

Best regards,
Marco

From: Christopher Polewczuk [mailto:cpolewc...@globalvisioninc.com]
Sent: Freitag, 2. September 2016 16:59
To: lcms-user@lists.sourceforge.net
Subject: Re: [Lcms-user] Using an embedded profile

More specifically I guess I am wondering if it is possible to reverse a 
transform with a profile.

Original Image 224,122,50
Transformed Image 224,122,18
Then convert from the transformed image back to 224,122,50

Thanks

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