Getting Started

Fast image processing library written in C. Decodes JPEG / PNG / WebP / AVIF / GIF / HEIC and encodes to WebP / AVIF / PNG via Lanczos-3 resize. Works with Node.js, Bun, and Deno.

• npm: https://www.npmjs.com/package/zenpix
• GitHub: https://github.com/tsukasa-art/zenpix

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Install

Node.js / Bun

npm install zenpix

ESM-only package. Requires "type": "module" in package.json. CommonJS (require) is not supported.

Deno

deno add npm:zenpix

Or use the npm: specifier directly:

import { decode, encodeAvif } from "npm:zenpix/deno";

Requires the --allow-ffi flag at runtime.

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Quick Start

import { decode, resize, encodeAvif } from "zenpix";
import { readFileSync, writeFileSync } from "fs";

const image   = decode(readFileSync("photo.jpg"));
const resized = resize(image, { width: 1920, height: 1080, fit: "cover" });
const avif    = encodeAvif(resized, { quality: 60, threads: 4 });
if (avif) writeFileSync("output.avif", avif);

Use convert() as a one-liner pipeline:

import { convert } from "zenpix";
import { readFileSync, writeFileSync } from "fs";

const result = convert(readFileSync("photo.jpg"), {
  resize: { width: 1920, height: 1080, fit: "cover" },
  encode: { format: "avif", quality: 60 },
});
if (result) writeFileSync("output.avif", result);

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Features

Feature	Description
Decode	JPEG / PNG / WebP / AVIF / GIF (first frame)
Resize	Lanczos-3, SIMD optimized (NEON/SSE2), fit modes: stretch / contain / cover
Encode	WebP / AVIF (configurable threads) / PNG
CLI	npx zenpix (batch & stdin/stdout support)
RGBA	Background removal, rounded corners, white background compositing
Pipeline	convert(): decode → crop → resize → encode in one call

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CPU Efficiency vs Sharp

zenpix excels in CPU efficiency on low-core VPS environments (3840×2160 → 1920×1080 AVIF, quality=60):

Tool	wall-clock	CPU user
Sharp (libvips auto-thread)	0.422s	2.630s
zenpix speed=6 (threads=14)	0.610s	1.060s

CPU user is ~40% of Sharp — roughly 2.5× more requests for the same CPU budget. See Benchmarks for details.