GENTHUMB

Generate fast WebP thumbnails from images, PDFs, Office files, spreadsheets, and text.

Installation

npm install genthumb

Supported Inputs

• Image: jpg, jpeg, png, gif, bmp, webp, tiff
• Document: pdf, docx, doc
• Presentation: pptx, ppt
• Spreadsheet: csv, tsv, xlsx, xls, xlsm, xlsb, ods
• Text: txt, text, md, markdown, log

Notes:

• csv and tsv are treated as spreadsheet inputs.
• For unknown formats, genthumb returns an error.

API

generateThumbnail(input, width, height, mimeType?) => Buffer

• input: string | Buffer
• width: number
• height: number
• mimeType (optional): string

Returns a WebP-encoded Buffer.

Usage

Path input:

import { writeFileSync } from 'node:fs';
import { generateThumbnail } from 'genthumb';

const thumb = generateThumbnail('./tests/documents/test-image.jpeg', 320, 240);
writeFileSync('./thumb.webp', thumb);

Buffer input:

import { readFileSync, writeFileSync } from 'node:fs';
import { generateThumbnail } from 'genthumb';

const source = readFileSync('./tests/documents/test-pdf.pdf');
const thumb = generateThumbnail(source, 320, 240, 'application/pdf');
writeFileSync('./thumb.webp', thumb);

Buffer input with MIME auto-detection:

import { readFileSync } from 'node:fs';
import { generateThumbnail } from 'genthumb';

const source = readFileSync('./tests/documents/test-image.jpeg');
const thumb = generateThumbnail(source, 320, 240);