@blazediff/core

@blazediff/core

High-performance pixel-by-pixel image comparison with block-based optimization. 20% faster than pixelmatch with zero memory allocation.

Installation

npm install @blazediff/core

API

blazediff(image1, image2, output, width, height, options)

Compare two images and return the number of different pixels.

Parameter	Type	Description
image1	Uint8Array | Uint8ClampedArray	First image data
image2	Uint8Array | Uint8ClampedArray	Second image data
output	Uint8Array | Uint8ClampedArray	Optional output buffer for diff visualization
width	number	Image width in pixels
height	number	Image height in pixels
options	object	Comparison options (optional)

Returns: Number of different pixels

Option	Type	Default	Description	Hint
threshold	number	0.1	Color difference threshold (0-1)	Lower values = more sensitive. 0.05 for strict comparison, 0.2+ for loose comparison
alpha	number	0.1	Background image opacity	Controls how faded unchanged pixels appear in diff output
aaColor	[number, number, number]	[255,255,0]	Anti-aliasing pixel color	Yellow by default. Set to red [255,0,0] to highlight anti-aliasing
diffColor	[number, number, number]	[255,0,0]	Different pixel color	Red by default. Use contrasting colors for better visibility
diffColorAlt	[number, number, number]	-	Alternative color for dark differences	Helps distinguish light vs dark pixel changes
includeAA	boolean	false	Include anti-aliasing in diff count	Set true to count anti-aliasing pixels as actual differences
diffMask	boolean	false	Output only differences (transparent background)	Useful for creating overlay masks or highlighting changes only
fastBufferCheck	boolean	true	Use fast buffer check using Buffer.compare	Set to false if images are processed differently, but look similiar

Usage

import blazediff from '@blazediff/core';

const diffCount = blazediff(
  image1.data,
  image2.data,
  outputData,
  width,
  height,
  {
    threshold: 0.1,
    alpha: 0.1,
    aaColor: [255, 255, 0],
    diffColor: [255, 0, 0],
    includeAA: false,
    diffMask: false,
    fastBufferCheck: true,
  }
);