Ocr Reciept Helper

Ocr Reciept Helper is a javascript library for extracting all the pairs of an item and a price of a reciept object from google ocr api response. Notice

• Specialized in the forms of reciepts in Korea
• Using Linear equation when detect a line of an item and a price
  • Work well with Rotated or sligtly curved reciepts
  • Poor work with curved or folded reciepts

Installation

Use npm to install ocr reciept helper.

npm install @ming822/ocr-reciept-helper

Usage

• response.json below is a response from your [google ocr api request] (https://cloud.google.com/vision/docs/ocr?)
• parameters when declare new instance
  • resJson : required. the object of google api response. It must have textAnnotations.
  • placeName : the name of the place of receipt.
  • sumKeywords
    • the words which refer sum.
    • they play a role of startline to detect lines of reciepts.
    • recommend to use common words at the bottom parts of receipt as it detects from bottom to top.
  • dateKeywords : the words which refer date.
  • skipwords : all the unnecessary words
• variables of an instance
  • whitespace
    • the minimum distance of phrase
    • an average width of all the character * 2
    • return value of calcSpace method
  • dateInfo
    • lines which contains dateKeywords.
    • also check lines of yyyy-mm-dd or yyyy-m-d through findDate in getDateInfo
  • priceTable
    • all the pairs of an item and a price of reciepts
    • pairs which are expected to be below the skipwords and above the sumKeywords are extracted through filterSkipwords

const recieptHelper = require('@ming822/ocr-reciept-helper')

const res = fs.readFileSync('response.json', {encoding:'utf-8', flag:'r'})
const resJson = JSON.parse(res)
const reciept = new recieptHelper(resJson)
console.log(reciept.priceTable)

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

License

MIT