# wvanbergen/chunky_png

Read/write access to PNG images in pure Ruby.

Repository: https://github.com/wvanbergen/chunky_png
Canonical: https://ross.abutalabs.com/products/chunky_png
Homepage: https://chunkypng.com
Language: Ruby
License: MIT
License Family: permissive
Topics: png, png-encoder, png-decoder, chunkypng, rdoc
Last push: 2024-06-03T10:22:43+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 6085, "days_push": 821, "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 1075, forks 104 (observed 2026-08-28T04:03:29.261258+00:00)

## What it is
A pure Ruby library for reading and writing PNG images with full support for all color modes, bit depths, transparency, and interlacing. It provides pixel-level and metadata access without requiring native image libraries like RMagick.

## Use cases
- read and write png files in ruby
- manipulate png pixels programmatically
- compose images with alpha blending
- read png metadata chunks
- generate png images from scratch without imagemagick

## When to choose
- you need PNG support in Ruby without native C dependencies
- portability across Ruby versions and platforms matters
- you need fine-grained pixel or chunk-level access

## When to avoid
- you need high performance image processing (consider OilyPNG or RMagick)
- you need formats other than PNG
- processing untrusted images - it is vulnerable to decompression bomb DoS attacks

## Facets
- artifact type: library
- maturity: maintenance
- function: image-processing, parser, serialization
- domain: image-processing, files, web-development
- platform: ruby, cross-platform
- tags: png, pure-ruby, pixel-manipulation, no-native-dependencies

## Member repositories
- wvanbergen/chunky_png (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:29.261258+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 2026-08-30T06:53:28.909349+00:00, confidence not recorded.
  - readme: https://github.com/wvanbergen/chunky_png (fetched 2026-08-28T04:03:29.261258+00:00, sha 8eb9ff214529)
- Data as of 2026-08-30T08:39:29.467469+00:00.