# woltapp/blurhash

A very compact representation of a placeholder for an image.

Repository: https://github.com/woltapp/blurhash
Canonical: https://ross.abutalabs.com/products/blurhash
Homepage: https://blurha.sh
Language: C
License: MIT
License Family: permissive
Last push: 2024-07-08T22:23:42+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 2625, "days_push": 786, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 17069, forks 379 (observed 2026-08-28T04:11:17.654303+00:00)

## What it is
BlurHash is a compact algorithm and multi-language library that encodes an image into a short 20-30 character string representing a blurred placeholder. The string can be stored alongside image URLs and decoded on clients to show a placeholder while the real image loads.

## Use cases
- show blurred image placeholders while images load
- encode images to compact placeholder strings on the backend
- avoid storing thumbnail images in the database
- decode blurhash strings into placeholder images on mobile apps
- add image placeholders as a field in JSON responses
- improve perceived loading performance in image-heavy UIs

## When to choose
- you need tiny image placeholders that fit in JSON or a database column
- you want a well-known, MIT-licensed algorithm with implementations in many languages
- you want smooth image loading experiences on web or mobile clients

## When to avoid
- you need actual thumbnails with recognizable detail rather than blurred color gradients
- you need animated or high-fidelity previews
- your platform has no available BlurHash implementation and porting is impractical

## Facets
- artifact type: library
- maturity: stable
- function: image-processing, serialization
- domain: image-processing, web-development, frontend, mobile-development
- platform: cross-platform, c, jvm, python
- tags: blurhash, image-placeholder, lazy-loading, encoder, decoder, swift, typescript

## Member repositories
- woltapp/blurhash (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:17.654303+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:03:30.687955+00:00, confidence not recorded.
  - readme: https://github.com/woltapp/blurhash (fetched 2026-08-28T04:11:17.654303+00:00, sha 7551f2fd1207)
  - homepage: https://blurha.sh (fetched 2026-08-29T08:01:32.293580+00:00, sha 41128ac7e903)
- Data as of 2026-08-30T08:39:29.467469+00:00.