validateImage

Validate an image before compression — format, dimensions, and basic integrity.

Signature

function validateImage(file: File | Blob): Promise<ImageValidationResult>

function isValidImage(file: File | Blob): Promise<boolean>

Parameters

file

File | Blob — candidate image.

Returns

ImageValidationResult

interface ImageValidationResult {
  isValid: boolean
  errors: string[]
  warnings: string[]
  actualFormat?: string
  declaredFormat?: string
  dimensions?: { width: number; height: number }
  fileSize?: number
}

Field	Description
isValid	true when there are no hard errors
errors	Blocking issues (corrupt, not an image, …)
warnings	Soft issues (MIME mismatch, huge dimensions, …)
actualFormat	Detected MIME / codec
declaredFormat	file.type when available
dimensions	Natural width/height when decodable
fileSize	Byte length

isValidImage(file) is equivalent to (await validateImage(file)).isValid.

Examples

Gate compression

import { validateImage, compress } from '@pantanal/pixu'

const validation = await validateImage(file)

if (!validation.isValid) {
  throw new Error(validation.errors.join('; '))
}

for (const warning of validation.warnings) {
  console.warn(warning)
}

const result = await compress(file, { quality: 0.8 })

Shorthand

import { isValidImage, compress } from '@pantanal/pixu'

if (await isValidImage(file)) {
  await compress(file)
}

Via compress options

await compress(file, {
  validateImage: true,
  quality: 0.8,
})

Related

• analyzeImage — content recommendations
• compress