Color Profiles¶
Standard RGB¶
sRGB is the default color space used when generating thumbnails. PhotoPrism and web browsers assume this color space for all pictures that do not have an embedded ICC color profile.
ICC Profiles¶
An ICC color profile for wide-gamut displays can optionally be embedded in image and video files. PhotoPrism renders all thumbnails with libvips (via govips), which preserves ICC profiles beyond sRGB and Display P3 by default:
| Environment | CLI Flag | Default | Description |
|---|---|---|---|
| PHOTOPRISM_THUMB_COLOR | --thumb-color | auto | Standard color PROFILE for thumbnails (auto, preserve, srgb, none) |
PHOTOPRISM_THUMB_LIBRARY is retained for backwards compatibility but has no effect — libvips is the only supported image-processing library since the April 2026 release.
Image colors may otherwise not be displayed correctly, which is particularly noticeable with ProPhoto RGB and Adobe RGB, as these cover a wide range of colors:
Color Detection¶
Color detection is performed while indexing using a 3x3 thumbnail that covers the top, bottom, and center of an image e.g. https://demo.photoprism.app/library/browse?color=green.