detect-image-grayscale-percentage

This library provides one API.Used to detect grayscale percentage for picture.You can use it judgment white and black image.

Usage

Install

pnpm add detect-image-grayscale-percentage
yarn add detect-image-grayscale-percentage
npm add detect-image-grayscale-percentage

Usage

import  detectImageGrayscalePercentage from detect-image-grayscale-percentage;

const image = new Image

image.onload = ()=>{
    image.src = "host/../path/image.jpg"
    const grayscalePercentage = await detectImageGrayscalePercentage(Image)
    if(grayscalePercentage===1){
        // image is white and black picture
        // do something...
    }

}

Second parameter type: GrayscaleStandardConfig

// include default value
class GrayscaleStandardConfig {
  numOfInspectionPoints = 1000; // How many points to detect
  diff = 5; // rgb value among maximum of difference 
  
  // The following values are mainly used for optimization
  
  // Mainly for random get detecting points more average,The following values will partition to 10 * 10 equal to 100 zones
  numOfZonesByX = 10;
  numOfZonesByY = 10;
  
  // "paddingRate" base on height and width,that part will not detecting
  paddingRate?: number //default:0  valable: 0-1
}

You can adjust the parameters util the appropriate your scene.

detectImageGrayscalePercentage(Image,{
    numOfInspectionPoints:10000
    diff: 50
})

When no partition spaces,might like this.

When partition spaces after,may like this.

How to work?

White-and-black picture of RGB values very close