Image Quantization Library in **TypeScript** *(MIT Licensed)*
npm install image-qComplete Image Quantization Library in TypeScript _(MIT License)_





- API Documentation and Usage
- Introduction
- Features
- Todo
- Breaking changes
- Changelog
- Credits
- References
- License
Image Color Number Reduction with alpha support using RGBQuant/NeuQuant/Xiaolin Wu's algorithms and Euclidean/Manhattan/CIEDE2000 color distance formulas in TypeScript
1. Platforms supported
- Browser (Chrome 7.0+, FireFox 4.0+, IE 10+, Opera 11.6+, Safari 5.1+)
- Node.js 6.0+
2. API
- Basic API: sync and promise-based async
- Advanced API: sync and generator-based
3. Builds
- dist/cjs/image-q.js - CommonJS
- dist/esm/image-q.js - ESM (ESNext)
- dist/cjs/image-q.js - UMD
4. Import
- HTMLImageElement
- HTMLCanvasElement
- NodeCanvas
- ImageData
- Array
- CanvasPixelArray
- Uint8Array
- Uint32Array
5. Color Distance
- Euclidean - 1/1/1/1 coefficients (originally used in Xiaolin Wu's Quantizer WuQuant)
- EuclideanBT709NoAlpha - BT.709 sRGB coefficients (originally used in RGBQuant)
- EuclideanBT709 BT.709 sRGB coefficients + alpha support
- Manhattan - 1/1/1/1 coefficients (originally used in NeuQuant)
- ManhattanBT709 - BT.709 sRGB coefficients
- ManhattanNommyde - see https://github.com/igor-bezkrovny/image-quantization/issues/4#issuecomment-234527620
- CIEDE2000 - CIEDE2000 (very slow)
- CIE94Textiles - CIE94 implementation for textiles
- CIE94GraphicArts - CIE94 implementation for graphic arts
- CMetric - see http://www.compuphase.com/cmetric.htm
- PNGQuant - used in pngQuant tool
6. Palette Quantizers
- NeuQuant (original code ported, integer calculations)
- NeuQuantFloat (floating-point calculations)
- RGBQuant
- WuQuant
7. Image Quantizers
- NearestColor
- ErrorDiffusionArray - two modes of error propagation are supported: xnview and gimp
1. FloydSteinberg
2. FalseFloydSteinberg
3. Stucki
4. Atkinson
5. Jarvis
6. Burkes
7. Sierra
8. TwoSierra
9. SierraLite
- ErrorDiffusionRiemersma - Hilbert space-filling curve is used
8. Output
- Uint32Array
- Uint8Array
image-q library into your project##### ES6 module
``javascript`
// will import ESM (ESNext) or UMD version depending on your bundler/node
import * as iq from 'image-q';
##### CommonJS
`javascript`
var iq = require('image-q');
##### As a global variable (Browser)
`html`
src="
type="text/javascript"
charset="utf-8"
>
Please refer to API Documentation and Usage
#### 2.1.1
+ PaletteQuantizer#quantize => PaletteQuantizer#quantizeSync
+ ImageQuantizer#quantize => ImageQuantizer#quantizeSync
#### 2.0.1 - 2.0.4 (2018-02-22)
+ EuclideanRgbQuantWOAlpha => EuclideanBT709NoAlpha
+ EuclideanRgbQuantWithAlpha => EuclideanBT709
+ ManhattanSRGB => ManhattanBT709
+ IImageDitherer => AbstractImageQuantizer
+ IPaletteQuantizer => AbstractPaletteQuantizer
+ PointContainer.fromNodeCanvas => PointContainer.fromHTMLCanvasElement
+ PointContainer.fromArray => PointContainer.fromUint8Array
+ PointContainer.fromBuffer (Node.js, new)
+ CMETRIC => CMetric
+ PNGQUANT => PNGQuant
+ SSIM Class => ssim function
1. ~~notification about progress~~
2. ~~riemersma dithering~~
3. ordered dithering <-- is there anyone who needs it?
4. readme update, more examples
5. demo update (latest image-q npm version should be used in demo)
##### 4.0.0
+ Test cases for different types of imports and requres added
##### 4.0.0-alpha
+ Try to solve exported bundle types problem. 'umd' bundle removed.
##### 3.0.8
+ Test case for issue #95 added
##### 3.0.7
+ Fixes #96: Fix minimumColorDistanceToDither (PR #97 by @pixelplanetdev)
##### 3.0.6
+ Fixes #95: "Always empty result in certain webpack / babel configs" (PR #98)
##### 3.0.4
+ Fixes issue "Module not found: Can't resolve 'core-js/fn/set-immediate' in ..."
##### 3.0.0
+ pnpm monorepo, esbuild for faster builds, typescript upgraded
##### 2.1.1
+ Basic (Simple) API implemented
+ see breaking changes
##### 2.0.5 (2018-02-23)
+ @types/node moved to 'dependencies'
##### 2.0.4 (2018-02-23)
+ documentation added
+ some refactorings/renames, see breaking changes
##### 2.0.3 (2018-02-22)
+ circular dependency removed
##### 2.0.2 (2018-02-22)
+ readme updated
##### 2.0.1 (2018-02-22)
+ progress tracking api (using es6 generators) added
+ strinct lint rules (+code cleanup/renames)
+ rollup (3 different versions - umd, cjs, esm + source maps + d.ts)
+ latest TypeScript
+ jest
+ snapshot tests
+ coverage (+coveralls)
+ greenkeeper
##### 1.1.1 (2016-08-28)
+ CIEDE2000 - incorrect calculation fixed
+ CIEDE2000 - alpha channel now has only 25% impact on color distance instead of 66%
+ CIE94 - added 2 types (textiles and graphics art) according to spec
+ CIE94 - alpha support added
+ rgb2xyz, lab2xyz, xyz2rgb, xyz2lab - gamma correction
+ lab2xyz, xyz2lab - refY should be 100 (1.00000) instead of 10 (0.10000)
+ manhattan with new (Nommyde) coefficients added
+ mocha tests added
+ webpack integration
+ image-q is now UMD module
+ travis-ci integration
+ typescript 2.0
+ indentation with 4 spaces
##### 0.1.4 (2015-06-24)
+ Refactoring
+ Riemersma dithering added (Hilbert Curve)
+ Readme.md updated
+ build.cmd updated
##### 0.1.3 (2015-06-16)
+ NeuQuant is fixed (again) according to original Anthony Dekker source code (all values should be integer)
+ Error Diffusion Dithering is now calculates error like XNVIEW
+ Refactoring
##### 0.1.2 (2015-06-16)
+ Documentation generation fixed
+ File name case problem fixed
##### 0.1.1 (2015-06-16)
+ Auto-generated documentation added
+ Refactoring
##### 0.1.0 (2015-06-16)
+ Code cleanup, removed unnecessary files
##### 0.0.5 (2015-06-16)
+ PNGQuant color distance added, need to check its quality
+ CIEDE2000 and CIE94 fixed for use in NeuQuant
+ NeuQuant is fixed according to original Anthony Dekker source code (all values should be integer)
+ Code refactoring and cleanup
* We have some slowdown because of red/green/blue/alpha normalization according to white point per each calculateRaw/calculateNormalized call
##### 0.0.4 (2015-06-15)
+ CIEDE2000 color distance equation optimized (original CIEDE2000 equation is available as class CIEDE2000_Original)
##### 0.0.3b (2015-06-11)
+ CMetric color distance fixed
##### 0.0.3a (2015-06-11)
+ Cleanup
+ Draft of CMetric color distance added
##### 0.0.2 (2015-06-10)
+ rgb2xyz & xyz2lab fixed. CIEDE2000 works much better now.
+ CIE94 distance formula added. More investigation is needed.
##### 0.0.1
+ Initial
Thanks to Leon Sorokin for information share and his original RGBQuant!
- Palette Quantization Algorithms
1. RGBQuant (Leon Sorokin) JavaScriptTypeScript
2. NeuQuant (Johan Nordberg) JavaScript
3. NeuQuant (Tim Oxley) JavaScript
4. NeuQuant (Devon Govett) C
5. NeuQuant32 (Stuart Coyle) C
6. Xiaolin Wu (Xiaolin Wu) C#
7. Xiaolin Wu (Smart-K8) C#
8. Xiaolin Wu w/ Alpha (Matt Wrock) How to add Alpha, Source Code GPLv3
9. MedianCut (mwcz)
- Image Quantization Algorithms
1. All (ImageMagik doc)
2. Error Diffusion dithering (Tanner Helland)
3. Riemersma dithering TODO: Check License
4. Ordered dithering (Joel Yliluoma)
- Color Distance Formulas
1. Euclidean Distance
2. Manhattan Distance
3. CIE94 Distance
- Source Code (Iulius Curt)
4. CIEDE2000
- Math and Test Data Table (PDF)
- Info
- Source Code (Greg Fiumara) CC#
- Source Code (THEjoezack) DRAFT!
- Online Calculator
5. Euclidean Distance w/o Alpha (RGBQuant)
6. Euclidean Distance w/o sRGB coefficients (Xiaolin Wu Quant)
7. Manhattan Distance w/o sRGB coefficients (NeuQuant)
8. CMetric
- Color conversion formulas
1. Pseudo-code
> Be sure to fix rgb2xyz/xyz2lab. Issue is with strange part of code: r = r > 0.04045 ? .... Check http://en.wikipedia.org/wiki/Lab_color_space
- Image Quality Assessment
1. SSIM info
2. SSIM (Rhys-e) Java License: MIT`
3. PSNR ? TBD
4. MSE ? TBD
- Other
1. HUSL (Boronine) - info
2. HUSL (Boronine) - code
3. Color Image Quantization for Frame Buffer Display
4. K-Means
5. Efficient Color Quantization by Hierarchical Clustering Algorithms
6. http://www.codeproject.com/Articles/66341/A-Simple-Yet-Quite-Powerful-Palette-Quantizer-in-C