Simple text recognition using Apple's Vision Framework (Part 3)

vision_text_recognition_example_3.swift

import UIKit
import Vision

let image = UIImage(named: "<image_name_goes_here>")

if let cgImage = image?.cgImage {
  let requestHandler = VNImageRequestHandler(cgImage: cgImage)

  let recognizeTextRequest = VNRecognizeTextRequest { (request, error) in
    // 1. Parse the results
    guard let observations = request.results as? [VNRecognizedTextObservation] else {
      return
    }
    
    // 2. Extract the data you want
    let recognizedStrings = observations.compactMap { observation in
      observation.topCandidates(1).first?.string
    }
    
    // 3. Display or update UI
    DispatchQueue.main.async {
      print(recognizedStrings)
    }
  }
  
  recognizeTextRequest.recognitionLevel = .fast
  
  DispatchQueue.global(qos: .userInitiated).async {
    do {
      try requestHandler.perform([recognizeTextRequest])
    } catch {
      print(error)
    }
  }
}