nanoimg v1.1.0

nanoimg

The art of making image files incredibly small. Can be used to compress images drastically without losing too much quality. Can lead to reduction of sometimes over 90% compared to the original file size.

Installation

npm install nanoimg

Usage

import { nano } from 'nanoimg';

// Default settings
nano({
    inputFile: "in.png",
    outputFile: "out.png",
});

// or
const outputBuffer = await nano({
    inputBuffer: buffer,
});

// Custom settings
const options = {
  enableColorQuantization: true,
  colorTolerance: 10,
  enableAlphaStripping: false,
  enableAdaptiveFiltering: true,
  floidSteinbergDitheringLevel: 0,
  enableColorLimit: false,
  colorLimit: 256,
  enableQualityReduction: true,
  quality: 90,
};
nano({
    inputFile: "in.png",
    outputFile: "out.png",
    options: options,
});

Used techniques

• Color Quantization
• To do Color Averaging
• Image compression
• Adaptive row filtering
• Color palette limitation
• Removal of error diffusion

Results

Default settings

Average reduction of 50-70% compared to the original file size. Usually no visible loss of quality.

Very high

Average reduction of 90-95% compared to the original file size. Noticeable but not too bad loss of quality.

Extreme

Average reduction of 95-99% compared to the original file size. Visible loss of quality.

This is an example of what extreme compression can do to an image (97% reduction):

To do

• Color averaging
• Better tests
• More documentation
• Support for more output formats
• Support for outputting to buffer
• Support for inputting from buffer

License

This project is licensed under the MIT License - see the LICENSE file for details