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class ExtractDataUseCase(private val textRecognizer: TextRecognizer) {

  suspend operator fun invoke(image: Image, rotationDegrees: Int): CardDetails {
    val imageInput = InputImage.fromMediaImage(image, rotationDegrees)
    val text = textRecognizer.process(imageInput).await().text
    return Extractor.extractData(text) //We are going to see this shortly
    }
}

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<meta-data
  android:name="com.google.mlkit.vision.DEPENDENCIES"
  android:value="ocr" />

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implementation 'com.google.android.gms:play-services-mlkit-text-recognition:16.1.0'

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private fun bindUseCases(cameraProvider: ProcessCameraProvider) {
  val preview = buildPreview()
  val takePicture = buildTakePicture()
  val cameraSelector = buildCameraSelector()

  cameraProvider.bindToLifecycle(this, cameraSelector, preview, takePicture)

  button.setOnClickListener {
    lifecycle.coroutineScope.launchWhenResumed {
      val imageProxy = takePicture.takePicture(executor)

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suspend fun ImageCapture.takePicture(executor: Executor): ImageProxy {
  return suspendCoroutine { continuation ->

    takePicture(executor, object : ImageCapture.OnImageCapturedCallback() {
      
      override fun onCaptureSuccess(image: ImageProxy) {
        continuation.resume(image)
        super.onCaptureSuccess(image)
      }

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private fun buildTakePicture(): ImageCapture = ImageCapture.Builder()
  .setTargetRotation(previewView.display.rotation)
  .setCaptureMode(ImageCapture.CAPTURE_MODE_MINIMIZE_LATENCY)
  .build()

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override fun onCreate(savedInstanceState: Bundle?) {
  super.onCreate(savedInstanceState)
  setContentView(R.layout.activity_main)
  lifecycle.coroutineScope.launchWhenResumed {
    bindUseCases(getCameraProvider())
  }
}

private fun bindUseCases(cameraProvider: ProcessCameraProvider) {
  val preview = buildPreview()

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private fun buildCameraSelector(): CameraSelector = CameraSelector.Builder()
  .requireLensFacing(CameraSelector.LENS_FACING_BACK)
  .build()

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suspend fun Context.getCameraProvider(): ProcessCameraProvider =
    suspendCoroutine { continuation ->
        ProcessCameraProvider.getInstance(this).apply {
            addListener(Runnable {
                continuation.resume(get())
            }, executor)
        }
    }

val Context.executor: Executor

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private fun buildPreview(): Preview = Preview.Builder()
  .build()
  .apply {
    setSurfaceProvider(previewView.createSurfaceProvider())
}