compressBatch

Compress multiple images with bounded concurrency.

Signature

function compressBatch(
  files: (File | Blob)[],
  options?: BatchCompressionOptions
): Promise<CompressionResult[]>

Parameters

files

Type	(File | Blob)[]
Required	Yes

Ordered list of images. Results keep the same order.

options

Type	BatchCompressionOptions

Extends CompressionOptions with:

Option	Type	Default	Description
concurrency	number	3	Max parallel compressions
onItemComplete	(result, index) => void	—	Fired when one file succeeds
onItemError	(error, index) => void	—	Fired when one file fails

All single-file options (quality, format, watermark, …) apply to every item.

Returns

Promise<CompressionResult[]> — one result per input, same index order.

When onItemError is provided, failed items may be omitted from the array (or handled only via the callback, depending on failure path). Prefer checking onItemError for robust UIs.

Error handling

• Without onItemError: the first failure rejects the whole promise.
• With onItemError: failures are reported per item; successful items still resolve.

Examples

Gallery upload

import { compressBatch } from '@pantanal/pixu'

const files = Array.from(input.files ?? [])

const results = await compressBatch(files, {
  quality: 0.8,
  maxWidth: 1920,
  format: 'auto',
  concurrency: 4,
  onItemComplete: (result, index) => {
    console.log(`#${index}`, result.compressedSize)
  },
  onItemError: (error, index) => {
    console.error(`#${index}`, error.message)
  },
})

PIXU batch

const results = await compressBatch(files, {
  format: 'image/pixu',
  enableSmartQuality: true,
  stripMetadata: true,
  concurrency: 2,
})

Related

• AdvancedBatchProcessor — retries, priority, pause/cancel
• compressStream — one-at-a-time async iteration
• compress — single file