probe-image-size

Get image size without full download. Supported image types: JPG, GIF, PNG, WebP, BMP, TIFF, SVG, PSD, ICO, AVIF, HEIC, HEIF.

Key features:

• small size, no heavy dependencies
• works with remote and local data
• effective with big images (speed/memory), download minimal data from remotes
• extracts orientation value when available
• easy to browserify (splitted to components)

Install

npm install probe-image-size

Example

const probe = require('probe-image-size');

// Get by URL
let result = await probe('http://example.com/image.jpg');
console.log(result); // =>
/*
  {
    width: xx,
    height: yy,
    type: 'jpg',
    mime: 'image/jpeg',
    wUnits: 'px',
    hUnits: 'px',
    url: 'http://example.com/image.jpg'
  }
*/


// By URL with options
let result = await probe('http://example.com/image.jpg', { rejectUnauthorized: false });
console.log(result);


// From the stream
let result = await probe(require('fs').createReadStream('image.jpg'));
console.log(result);


// From a Buffer (sync)
let data = require('fs').readFileSync('image.jpg');
console.log(probe.sync(data));

Security notes

Network requests. The library uses GET requests to extract image metadata. The default HTTP wrapper supports requests to localhost and private networks. Such requests are not a security issue on their own.

If HTTP(S) GET requests to internal services are a concern, block access to local and private networks at the interface or network level. A separate VM lets you configure these restrictions independently.

Image dimensions. For untrusted images, treat the returned width and height as untrusted too. Check that they are within ranges acceptable for your application.

API

Note:

• You can access/browserify stream.js / http.js / sync.js directly.
• If you don't like http.js dependencies, you can create your own wrapper for stream.js.

probe(src [, options|keepOpen]) -> Promise

See Security notes when working with untrusted input.

• src can be of this types:
  • String - URL to fetch
  • Stream - readable stream
• options - HTTP only. See needle documentation, and customized defaults.
• keepOpen (Boolean) - stream only. Keep stream open after parser finishes (input stream will be closed by default)

result (Promise) contains:

{
  width: XX,
  height: YY,
  length: ZZ,   // byte length of the file (if available, HTTP only)
  type: ...,    // image 'type' (usual file name extention)
  mime: ...,    // mime type
  wUnits: 'px', // width units type ('px' by default, can be different for SVG)
  hUnits: 'px', // height units type ('px' by default, can be different for SVG)
  url: ...,     // HTTP only, last url for the image in chain of redirects
                // (if no redirects, same as src)

  // optional, image orientation (from Exif), number from 1 to 8;
  // you may wish to swap width and height if orientation is >= 5
  orientation: X,

  // optional, full list of sizes for ICO (always) and AVIF (if multiple images)
  variants: [ { width, height }, ... ] | undefined
}

Width and height in the output object represent image size before any transformations (orientation, cropping) are applied. Orientation is returned separately, which you may wish to apply afterwards depending on browser support (browsers only support JPEG orientation for now). See known issues for details.

Returned errors can be extended with 2 fields:

• code - equals to ECONTENT if the library failed to parse the file;
• status - equals to a HTTP status code if it receives a non-200 response.

probe.sync(src) -> result|null

Sync version can eat arrays, typed arrays and buffers. On success it returns the same result as async version. On fail it returns null.

[!NOTE]

Formats like JPEG & TIFF can store size anywhere (far from the head). That usually does not happens, but if you need guarantees - always provide full file content to sync methods. We strongly recommend to use async version as memory-friendly.

Similar projects

• image-size

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