https://github.com/image-js/fast-bmp
Library to encode BMP images
https://github.com/image-js/fast-bmp
bmp image
Last synced: 6 months ago
JSON representation
Library to encode BMP images
- Host: GitHub
- URL: https://github.com/image-js/fast-bmp
- Owner: image-js
- Created: 2016-12-12T10:16:27.000Z (almost 9 years ago)
- Default Branch: main
- Last Pushed: 2025-04-11T14:44:50.000Z (6 months ago)
- Last Synced: 2025-04-11T15:47:42.707Z (6 months ago)
- Topics: bmp, image
- Language: TypeScript
- Homepage:
- Size: 1.15 MB
- Stars: 4
- Watchers: 7
- Forks: 1
- Open Issues: 4
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
Awesome Lists containing this project
README
# fast-bmp
Maintained by Zakodium
[![NPM version][npm-image]][npm-url]
[![Test coverage][codecov-image]][codecov-url]
[![npm download][download-image]][download-url]
A library for encoding and decoding bmp image file format.
References:
- [Wikipedia BMP format page](https://en.wikipedia.org/wiki/BMP_file_format)
- [Microsoft BMPV5 format page](https://learn.microsoft.com/en-us/windows/win32/api/wingdi/ns-wingdi-bitmapv5header)
# Supported features
This library only supports V5 headers.
- binary (1-bit per pixel)
- greyscale (8-bits per pixel)
- RGB (24-bits per pixel)
- RGBA (32-bits per pixel)
# Usage
## Encoding
```js
import { encode } from 'fast-bmp';
// 0 0 0 0 0
// 0 1 1 1 0
// 0 1 0 1 0
// 0 1 1 1 0
// 0 0 0 0 0
const data = new Uint8Array([
0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0,
]);
const imageData = {
width: 5,
height: 5,
data,
bitsPerPixel: 1,
components: 1,
channels: 1,
};
// Encode returns a Uint8Array.
const encoded = encode(imageData);
fs.writeFileSync('image.bmp', encoded);
```
## Decoding
```ts
import { decode } from 'fast-bmp';
// 0 0 0 0 0
// 0 1 1 1 0
// 0 1 0 1 0
// 0 1 1 1 0
// 0 0 0 0 0
const buffer = fs.writeFileSync('image.bmp');
const imageData = decode(buffer);
/* Returns object:
{
width: 5,
height: 5,
data: new Uint8Array([
0, 0, 0, 0, 0,
0, 1, 1, 1, 0,
0, 1, 0, 1, 0,
0, 1, 1, 1, 0,
0, 0, 0, 0, 0,
]),
bitsPerPixel: 1,
components: 1,
channels: 1,
colorMasks: [0x00ff0000, 0x0000ff00, 0x000000ff],
compression: 0,
xPixelsPerMeter: 2835,
yPixelsPerMeter: 2835,
}
*/
```
[npm-image]: https://img.shields.io/npm/v/fast-bmp.svg?style=flat-square
[npm-url]: https://www.npmjs.com/package/fast-bmp
[codecov-image]: https://img.shields.io/codecov/c/github/image-js/fast-bmp.svg?style=flat-square
[codecov-url]: https://codecov.io/gh/image-js/fast-bmp
[download-image]: https://img.shields.io/npm/dm/fast-bmp.svg?style=flat-square
[download-url]: https://www.npmjs.com/package/fast-bmp