rastermill

library0.3.1jsnpmunverified

Rastermill is a fast, portable image processing library for Node.js agents, currently at version 0.3.1. It uses Photon for in-process image operations and can fall back to native tools (sips, ImageMagick, GraphicsMagick, ffmpeg) for formats like HEIC/AVIF. Key differentiators: configurable pixel limits for safety, automatic format detection and metadata stripping, and support for auto-orientation. Types are shipped. Requires Node >= 22. Release cadence is not specified.

testing

npm install rastermill

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · RASTERMILL

rastermill

testingjavascriptv0.3.1

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

createRastermill

✓ import { createRastermill } from 'rastermill'

✗ const createRastermill = require('rastermill')

ESM only since v0.1.0; CJS require will fail.

probe

✓ import { probe } from 'rastermill'

Same ESM restriction. Available as named export.

encode

✓ import { encode } from 'rastermill'

Standalone function backed by default lazy instance.

transparency

✓ import { transparency } from 'rastermill'

Reports separate hasAlphaChannel and hasTransparentPixels.

Create a Rastermill instance, probe an image, and encode it as JPEG with resize and quality.

import { createRastermill } from 'rastermill'; import { readFile } from 'node:fs/promises'; const rastermill = createRastermill({ execution: 'auto', limits: { inputPixels: 25000000, outputPixels: 25000000 }, }); const imageBuffer = await readFile('input.heic'); const info = await rastermill.probe(imageBuffer); console.log(info.format, info.width, info.height); const jpeg = await rastermill.encode(imageBuffer, { format: 'jpeg', resize: { maxSide: 1600 }, quality: 85, }); console.log(jpeg.mimeType, jpeg.bytes);

Debug

Known issues

breakingEngine requirement: Node >= 22. Older versions will not work.

fix

Upgrade to Node 22 or later.

affects: <0.1.0

deprecatedPhoton does not expose EXIF/GPS/ICC/XMP APIs; metadata preservation is limited.

fix

Use metadata: 'preserve' only when no transform is applied; otherwise metadata is stripped.

affects: >=0.1.0

gotchaWebP quality control requires an external backend (e.g., cwebp) because Photon's WebP encoder does not accept quality setting.

fix

Set execution: 'auto' or 'external' to use native tools for WebP.

affects: >=0.1.0

breakingESM only; CJS require() will throw Module not found.

fix

Use import syntax or dynamic import.

affects: >=0.1.0

gotchaencode() may succeed but return an empty buffer if input pixel limit is exceeded; error handling needed.

fix

Check response.bytes > 0 or catch probe/encode errors.

affects: >=0.1.0

Errors

Common errors & fixes

SyntaxError: The requested module 'rastermill' does not provide an export named 'createRastermill'

Using CommonJS require instead of ESM import.

fix

Change require('rastermill') to import { createRastermill } from 'rastermill', or use dynamic import.

Error: Unsupported format

Input image format not recognized or not supported by any backend.

fix

Check the input buffer or file; supported formats: HEIC, JPEG, PNG, WebP, AVIF, etc. Ensure external tools are installed if needed.

Upgrade

Version history

0.3.1latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

7 hits · last 30 days

node

Amazon

Resources

githubhttps://github.com/openclaw/rastermill ↗

packagerastermill ↗

homepagehttps://rastermill.com/ ↗