# antimatter15/whammy

A real time javascript webm encoder based on a canvas hack

Repository: https://github.com/antimatter15/whammy
Canonical: https://ross.abutalabs.com/products/whammy
Homepage: http://antimatter15.github.com/whammy/clock.html
Language: JavaScript
License: MIT
License Family: permissive
Last push: 2024-07-14T09:41:35+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": 5191, "days_push": 780, "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 1032, forks 178 (observed 2026-08-28T04:03:18.257516+00:00)

## What it is
Whammy is a small JavaScript library that encodes canvas frames into WebM video files entirely in the browser by reusing WebP-encoded VP8 image data. It works only in browsers with WebP encoding support (essentially Chrome) and produces intraframe-only video without interframe compression.

## Use cases
- record canvas animations to a webm video in the browser
- convert webp image sequences into a webm video client-side
- capture real-time canvas drawings as downloadable video
- encode frames to video without a server
- avoid storing frames as data urls or slow gif encoding

## When to choose
- you need fast, fully client-side video encoding from canvas content
- your target is Chrome and WebM output is acceptable
- file size matters less than encoding speed

## When to avoid
- you need interframe compression or small file sizes
- you must support browsers without WebP encoding like Firefox or Safari
- you need production-grade video encoding with audio

## Facets
- artifact type: library
- maturity: maintenance
- function: video-processing, image-processing
- domain: media, web-development, browser-extensions
- platform: browser
- tags: webm, vp8, canvas, client-side-encoding, webp

## Member repositories
- antimatter15/whammy (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:18.257516+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 2026-08-30T07:06:44.003405+00:00, confidence not recorded.
  - readme: https://github.com/antimatter15/whammy (fetched 2026-08-28T04:03:18.257516+00:00, sha 37d24c546c56)
  - registry_npm: https://registry.npmjs.org/whammy (fetched 2026-08-29T13:06:26.234545+00:00, sha 3302e69059d3)
- Data as of 2026-08-30T08:39:29.467469+00:00.