I have two classes: QrActivity, where camera is turned on to scan qr codes, and BarcodeAnalyzer, where image analyze process is going. I am doing it with cameraX and ML Kit.
That's my QrActivity:
package ge.softservice.nfcwithactivties
import android.Manifest
import android.content.pm.PackageManager
import android.os.Bundle
import android.util.Log
import android.widget.Toast
import androidx.appcompat.app.AppCompatActivity
import androidx.camera.core.*
import androidx.camera.lifecycle.ProcessCameraProvider
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import kotlinx.android.synthetic.main.activity_qr.*
import java.io.File
import java.util.concurrent.ExecutorService
import java.util.concurrent.Executors
class QrActivity : AppCompatActivity() {
private var preview: Preview? = null
private var imageAnalyzer: ImageAnalysis? = null
private var camera: Camera? = null
private lateinit var outputDirectory: File
private lateinit var cameraExecutor: ExecutorService
override fun onRequestPermissionsResult(
requestCode: Int, permissions: Array<String>, grantResults:
IntArray
) {
if (requestCode == REQUEST_CODE_PERMISSIONS) {
if (allPermissionsGranted()) {
startCamera()
} else {
Toast.makeText(
this,
"Permissions not granted by the user.",
Toast.LENGTH_SHORT
).show()
finish()
}
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_qr)
// Request camera permissions
if (allPermissionsGranted()) {
startCamera()
} else {
ActivityCompat.requestPermissions(
this, REQUIRED_PERMISSIONS, REQUEST_CODE_PERMISSIONS
)
}
// outputDirectory = getOutputDirectory()
cameraExecutor = Executors.newSingleThreadExecutor()
}
private fun startCamera() {
val cameraProviderFuture = ProcessCameraProvider.getInstance(this)
cameraProviderFuture.addListener(Runnable {
// Used to bind the lifecycle of cameras to the lifecycle owner
val cameraProvider: ProcessCameraProvider = cameraProviderFuture.get()
// Preview
preview = Preview.Builder()
.build()
// Select back camera
val cameraSelector =
CameraSelector.Builder().requireLensFacing(CameraSelector.LENS_FACING_BACK).build()
try {
// Unbind use cases before rebinding
cameraProvider.unbindAll()
// Bind use cases to camera
camera = cameraProvider.bindToLifecycle(
this, cameraSelector, preview
)
preview?.setSurfaceProvider(viewFinder.createSurfaceProvider(/*camera?.cameraInfo*/))
} catch (exc: Exception) {
Log.e(TAG, "Use case binding failed", exc)
}
}, ContextCompat.getMainExecutor(this))
}
private fun takePhoto() {
// TODO
}
private fun allPermissionsGranted() = REQUIRED_PERMISSIONS.all {
ContextCompat.checkSelfPermission(
baseContext, it
) == PackageManager.PERMISSION_GRANTED
}
/* fun getOutputDirectory(): File {
val mediaDir = externalMediaDirs.firstOrNull()?.let {
File(it, resources.getString(R.string.app_name)).apply { mkdirs() } }
return if (mediaDir != null && mediaDir.exists())
mediaDir else filesDir
}*/
companion object {
private const val TAG = "CameraXBasic"
private const val FILENAME_FORMAT = "yyyy-MM-dd-HH-mm-ss-SSS"
private const val REQUEST_CODE_PERMISSIONS = 10
private val REQUIRED_PERMISSIONS = arrayOf(Manifest.permission.CAMERA)
}
}
Thats' my Barcode analyzer:
package ge.softservice.nfcwithactivties
import android.annotation.SuppressLint
import android.content.Context
import android.widget.Toast
import androidx.camera.core.ImageAnalysis
import androidx.camera.core.ImageProxy
import com.google.firebase.ml.vision.FirebaseVision
import com.google.firebase.ml.vision.barcode.FirebaseVisionBarcode
import com.google.firebase.ml.vision.barcode.FirebaseVisionBarcodeDetectorOptions
import com.google.firebase.ml.vision.common.FirebaseVisionImage
import com.google.firebase.ml.vision.common.FirebaseVisionImageMetadata
class BarcodeAnalyzer : ImageAnalysis.Analyzer {
lateinit var context: Context;
private fun degreesToFirebaseRotation(degrees: Int): Int = when(degrees) {
0 -> FirebaseVisionImageMetadata.ROTATION_0
90 -> FirebaseVisionImageMetadata.ROTATION_90
180 -> FirebaseVisionImageMetadata.ROTATION_180
270 -> FirebaseVisionImageMetadata.ROTATION_270
else -> throw Exception("Rotation must be 0, 90, 180, or 270.")
}
@SuppressLint("UnsafeExperimentalUsageError")
override fun analyze(imageProxy: ImageProxy) {
// val degrees by Delegates.notNull<Int>()
val mediaImage = imageProxy.image
val imageRotation = degreesToFirebaseRotation(imageProxy.imageInfo.rotationDegrees)
if (mediaImage != null) {
val image = FirebaseVisionImage.fromMediaImage(mediaImage, imageRotation)
// Pass image to an ML Kit Vision API
val options = FirebaseVisionBarcodeDetectorOptions.Builder()
.setBarcodeFormats(
FirebaseVisionBarcode.FORMAT_QR_CODE
)
.build()
val detector = FirebaseVision.getInstance().getVisionBarcodeDetector(options)
val result = detector.detectInImage(image)
.addOnSuccessListener { barcodes ->
// Task completed successfully
Toast.makeText(context, "it works", Toast.LENGTH_SHORT).show()
}
.addOnFailureListener {
// Task failed with an exception
Toast.makeText(context, "something went wrong", Toast.LENGTH_SHORT).show()
}
}
}
}
I also tried to put this code instead of BarcodeAnalyzer into QrActivity class, but then image value is not recognized.
val options = FirebaseVisionBarcodeDetectorOptions.Builder()
.setBarcodeFormats(
FirebaseVisionBarcode.FORMAT_QR_CODE
)
.build()
val detector = FirebaseVision.getInstance().getVisionBarcodeDetector(options)
val result = detector.detectInImage(image)
.addOnSuccessListener { barcodes ->
// Task completed successfully
Toast.makeText(context, "it works", Toast.LENGTH_SHORT).show()
}
.addOnFailureListener {
// Task failed with an exception
Toast.makeText(context, "something went wrong", Toast.LENGTH_SHORT).show()
}
if I put it in BarcodeAnalyzer, where it is now, there is no error but result value is gray color and not used.
I found this project and tried to do similar but in my project it shows me errors: https://github.com/Lavanyagaur22/Visitor-Card
I also tried this and other tutorials but lots of things are unclear for me: https://www.bignerdranch.com/blog/using-firebasemlkit-with-camerax/
I tried to do instance in QrActivty class of BarcodeAnalyzer but is shows me errors.
I am following google's firebase ML Kit tutorial but still doesn't work for me: https://firebase.google.com/docs/ml-kit/android/read-barcodes#kotlin+ktx_1
So, how can I connect BarcodeAnalyzer class to QrActivity class or how to make an instance to recognize qr code?
