30eef7d036 | ||
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.. | ||
lib | ||
CHANGELOG.md | ||
LICENSE | ||
README.md | ||
http.js | ||
index.js | ||
package.json | ||
stream.js | ||
sync.js |
README.md
probe-image-size
Get image size without full download. Supported image types: JPG, GIF, PNG, WebP, BMP, TIFF, SVG, PSD.
Key features:
- small size, no heavy dependencies
- works with remote and local data
- effective with big images (speed/memory), download minimal data from remotes
- easy to browserify (splitted to components)
Install
npm install probe-image-size --save
Example
var probe = require('probe-image-size');
// Get by URL
//
probe('http://example.com/image.jpg').then(result => {
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
//
probe('http://example.com/image.jpg', { timeout: 5000 }).then(function (result) {
console.log(result);
});
// With callback
//
probe('http://example.com/image.jpg', function (err, result) {
console.log(result);
});
// From the stream
//
var input = require('fs').createReadStream('image.jpg');
probe(input).then(result => {
console.log(result);
// terminate input, depends on stream type,
// this example is for fs streams only.
input.destroy();
});
// From a Buffer
//
var data = require('fs').readFileSync('image.jpg');
console.log(probe.sync(data));
API
probe(src [, options, callback]) -> Promise
src
can be of this types:
- String - URL to fetch
- Stream - readable stream
options
- HTTP only. See got
documentation.
Defaults changed to { retries: 1, timeout: 30000 }
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: ..., // last url for the image in chain of redirects (if no redirects, same as src) (HTTP only)
}
Returned errors can be extended with 2 fields:
code
- equals toECONTENT
if the library failed to parse the file;status
- equals to a HTTP status code if it receives a non-200 response.
If callback (legacy node style) provided, Promise
will not be returned.
Note 1. If you use Stream
as source, it's your responsibility to close that
stream in callback. In other case you can get memory leak, because stream will
be left in paused state. With http requests that's not a problem - everything
is released automatically, as soon as possible.
Note 2. We still support legacy v2.x signature for http probe (src
is
Object as described in request). But it
will be deprecated in next versions.
sync.probe(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.