56 lines
949 B
Markdown
56 lines
949 B
Markdown
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# is-png [](https://travis-ci.org/sindresorhus/is-png)
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> Check if a Buffer/Uint8Array is a [PNG](http://en.wikipedia.org/wiki/Portable_Network_Graphics) image
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Used by [image-type](https://github.com/sindresorhus/image-type).
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## Install
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```sh
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$ npm install --save is-png
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```
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## Usage
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##### Node.js
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```js
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var readChunk = require('read-chunk'); // npm install read-chunk
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var isPng = require('is-png');
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var buffer = readChunk.sync('unicorn.png', 0, 8);
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isPng(buffer);
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//=> true
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```
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##### Browser
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```js
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var xhr = new XMLHttpRequest();
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xhr.open('GET', 'unicorn.png');
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xhr.responseType = 'arraybuffer';
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xhr.onload = function () {
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isPng(new Uint8Array(this.response));
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//=> true
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};
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xhr.send();
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```
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## API
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### isPng(buffer)
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Accepts a Buffer (Node.js) or Uint8Array.
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It only needs the first 8 bytes.
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## License
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MIT © [Sindre Sorhus](http://sindresorhus.com)
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