Glossary
ICC profile
An ICC profile is a colour description embedded in an image so that viewers reproduce its colours consistently.
Updated
Pixel values are meaningless without a definition of what colour each number represents. An ICC profile supplies that definition, so an image looks the same across different screens and print processes.
Remove it and software falls back on a guess, usually sRGB. For an image in a wider gamut the result is visibly flat and desaturated — the file is technically smaller and looks worse.
It carries nothing identifying. Profiles are drawn from a small set of industry standards shared by enormous numbers of files, so keeping one reveals nothing about you.
JPEG has a related trap in the APP14 segment, which declares the colour transform. Removing it turns CMYK and YCCK JPEGs into colour-inverted messes, which is why tools that blindly drop every marker segment get those files wrong.
Related terms
- Orientation tag — The orientation tag is the EXIF field telling a viewer which way up an image should be displayed.
- APP marker segment — An APP marker segment is a labelled block in a JPEG file where applications store metadata, ahead of the compressed image data.
- Lossless — Lossless means the image data comes out bit-for-bit identical to what went in.