decode-tiff
Version:
Lightweight tiff decoder
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Markdown
# decode-tiff
[](https://badge.fury.io/js/decode-tiff)
[](https://opensource.org/licenses/MIT)
:zap: A lightweight pure JavaScript TIFF decoder. :art:
## How to use it
### With Node.js
```sh
npm i tiff-decode
```
The following example reads .tiff and converts to .png file using [pngjs](https://www.npmjs.com/package/pngjs).
```js
const { decode } = require("decode-tiff");
const { PNG } = require("pngjs");
const fs = require("fs");
const { width, height, data } = decode(fs.readFileSync(__dirname + "/lena_color.tiff"));
const png = new PNG({ width, height });
png.data = data;
fs.writeFileSync(__dirname + "/lena.png", PNG.sync.write(png));
```
### With Browser
Download script file from [dist/decode-tiff.min.js](https://raw.githubusercontent.com/Quramy/decode-tiff/master/dist/decode-tiff.min.js). Alternatively you can use Module Bundler, such as webpack, Browserify, and Rollup.
This example shows metadata of the dropped file. [Working demonstration is here.](https://quramy.github.io/decode-tiff/)
```html
<html>
<head></head>
<body>
<div id="drop">
<p>Drop TIFF file here!</p>
</div>
<script src="decode-tiff.min.js"></script>
<script>
const { decode } = window.decodeTiff;
const elm = document.getElementById("drop");
elm.addEventListener("dragenter", e => e.preventDefault());
elm.addEventListener("dragover", e => e.preventDefault());
elm.addEventListener("drop", e => {
e.preventDefault();
const file = e.dataTransfer.files[0];
const reader = new FileReader();
reader.addEventListener("load", e => {
const arrayBuffer = e.target.result;
const { width, height, ifdEntries } = decode(arrayBuffer);
const metadata = JSON.stringify({ width, height, ifdEntries }, null, 2);
elm.innerHTML = `<pre>${metadata}</pre>`;
});
reader.readAsArrayBuffer(file);
});
</script>
</body>
</html>
```
## API
### `decode(buffer: ArrayBuffer | Buffer, options?: { singlePage?: boolean }): TiffImage | TiffImage[]`
- params
- `buffer` - *Required* - Buffer of the target TIFF image. Node.js Buffer and ECMA Script's ArrayBuffer are acceptable.
- `options.singlePage` - *Optional (default: `true`)* - If true, this function returns a single TiffImage object. If the input has 2 or more pages, return value will be the first page.
- returns
- `TiffImage` - An object.
- `TiffImage.width` - *number* - Width of the input image.
- `TiffImage.height` - *number* - Height of the input image.
- `TiffImage.data` - *Uint8Array* - Image pixel data. Every pixel consists 4 bytes: R, G, B, A (opacity)
- `TiffImage.ifdEntries` - *{[key: string]: Array}* - Each IFD entries of the input image.
## Compatibility
- Byte Order
- [x] Little endian
- [x] Big endian
- Color resolusion
- [x] 32bit Full Colors
- [x] 24bit Full Colors
- [x] 8bit Gray scale
- [x] 4bit Gray scale
- [ ] Palette-Color
- [ ] Bilevel(white)
- [ ] Bilevel(black)
- Compression
- [x] No Compression
- [ ] CCITT Group 3
- [ ] LZW Compression
- [ ] ZIP
- [ ] Packbits
- Masking
- [ ] Transparency Mask
## License
MIT. See LICENSE.txt.