Improve QRS scan

app/src/play/java/io/nekohasekai/sfa/vendor/MLKitQRCodeAnalyzer.kt

@@ -8,12 +8,15 @@ import com.google.mlkit.vision.barcode.BarcodeScannerOptions
 import com.google.mlkit.vision.barcode.BarcodeScanning
 import com.google.mlkit.vision.barcode.common.Barcode
 import com.google.mlkit.vision.common.InputImage
+import io.nekohasekai.sfa.ui.profile.QRCodeCropArea
+import io.nekohasekai.sfa.ui.profile.QRCodeSmartCrop
 
 // kanged from: https://github.com/G00fY2/quickie/blob/main/quickie/src/main/kotlin/io/github/g00fy2/quickie/QRCodeAnalyzer.kt
 
 class MLKitQRCodeAnalyzer(
     private val onSuccess: ((String) -> Unit),
     private val onFailure: ((Exception) -> Unit),
+    private val onCropArea: ((QRCodeCropArea?) -> Unit)? = null,
 ) : ImageAnalysis.Analyzer {
     private val barcodeScanner =
         BarcodeScanning.getClient(
@@ -26,6 +29,7 @@ class MLKitQRCodeAnalyzer(
     private var failureOccurred = false
     private var failureTimestamp = 0L
 
+    private var yDataBuffer: ByteArray? = null
     private var pixelBuffer: IntArray? = null
 
     @ExperimentalGetImage
@@ -38,6 +42,7 @@ class MLKitQRCodeAnalyzer(
         val nowMills = System.currentTimeMillis()
         if (failureOccurred && nowMills - failureTimestamp < 5000L) {
             failureTimestamp = nowMills
+            onCropArea?.invoke(null)
             image.close()
             return
         }
@@ -47,33 +52,75 @@ class MLKitQRCodeAnalyzer(
             .addOnSuccessListener { codes ->
                 val rawValue = codes.firstOrNull()?.rawValue
                 if (rawValue != null) {
+                    onCropArea?.invoke(null)
                     onSuccess(rawValue)
                     image.close()
                 } else {
-                    tryInvertedScan(image)
+                    val yData = image.toYData().copyOf()
+                    val rotation = image.imageInfo.rotationDegrees
+                    val cropArea = QRCodeSmartCrop.findCropArea(yData, image.width, image.height, rotation)
+                    onCropArea?.invoke(cropArea)
+                    if (cropArea == null) {
+                        tryInvertedScan(yData, image.width, image.height, rotation) { image.close() }
+                    } else {
+                        val cropWidth = cropArea.right - cropArea.left
+                        val cropHeight = cropArea.bottom - cropArea.top
+                        val bitmap = toLumaBitmap(
+                            yData,
+                            image.width,
+                            cropArea.left,
+                            cropArea.top,
+                            cropWidth,
+                            cropHeight,
+                            invert = false,
+                        )
+                        barcodeScanner.process(InputImage.fromBitmap(bitmap, rotation))
+                            .addOnSuccessListener { cropCodes ->
+                                val cropValue = cropCodes.firstOrNull()?.rawValue
+                                if (cropValue != null) {
+                                    onSuccess(cropValue)
+                                    image.close()
+                                } else {
+                                    tryInvertedScan(yData, image.width, image.height, rotation) { image.close() }
+                                }
+                            }
+                            .addOnFailureListener {
+                                tryInvertedScan(yData, image.width, image.height, rotation) { image.close() }
+                            }
+                            .addOnCompleteListener {
+                                bitmap.recycle()
+                            }
+                    }
                 }
             }
             .addOnFailureListener {
                 failureOccurred = true
                 failureTimestamp = System.currentTimeMillis()
+                onCropArea?.invoke(null)
                 onFailure(it)
                 image.close()
             }
     }
 
-    private fun tryInvertedScan(image: ImageProxy) {
-        val inverted = image.toInvertedBitmap()
-        barcodeScanner.process(InputImage.fromBitmap(inverted, image.imageInfo.rotationDegrees))
+    private fun tryInvertedScan(
+        yData: ByteArray,
+        width: Int,
+        height: Int,
+        rotationDegrees: Int,
+        onComplete: () -> Unit,
+    ) {
+        val inverted = toLumaBitmap(yData, width, 0, 0, width, height, invert = true)
+        barcodeScanner.process(InputImage.fromBitmap(inverted, rotationDegrees))
             .addOnSuccessListener { codes ->
                 codes.firstOrNull()?.rawValue?.let { onSuccess(it) }
             }
             .addOnCompleteListener {
                 inverted.recycle()
-                image.close()
+                onComplete()
             }
     }
 
-    private fun ImageProxy.toInvertedBitmap(): Bitmap {
+    private fun ImageProxy.toYData(): ByteArray {
         val yPlane = planes[0]
         val yBuffer = yPlane.buffer.duplicate()
         val rowStride = yPlane.rowStride
@@ -81,16 +128,41 @@ class MLKitQRCodeAnalyzer(
         val height = height
         val size = width * height
 
-        val bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888)
-        val pixels = pixelBuffer?.takeIf { it.size >= size } ?: IntArray(size).also { pixelBuffer = it }
-
-        for (row in 0 until height) {
-            yBuffer.position(row * rowStride)
-            for (col in 0 until width) {
-                val y = 255 - (yBuffer.get().toInt() and 0xFF)
-                pixels[row * width + col] = (0xFF shl 24) or (y shl 16) or (y shl 8) or y
+        val yData = yDataBuffer?.takeIf { it.size >= size } ?: ByteArray(size).also { yDataBuffer = it }
+        if (rowStride == width) {
+            yBuffer.get(yData, 0, size)
+        } else {
+            for (row in 0 until height) {
+                yBuffer.position(row * rowStride)
+                yBuffer.get(yData, row * width, width)
             }
         }
+        return yData
+    }
+
+    private fun toLumaBitmap(
+        yData: ByteArray,
+        srcWidth: Int,
+        left: Int,
+        top: Int,
+        width: Int,
+        height: Int,
+        invert: Boolean,
+    ): Bitmap {
+        val size = width * height
+        val pixels = pixelBuffer?.takeIf { it.size >= size } ?: IntArray(size).also { pixelBuffer = it }
+
+        var index = 0
+        for (row in 0 until height) {
+            val rowOffset = (top + row) * srcWidth + left
+            for (col in 0 until width) {
+                val y = yData[rowOffset + col].toInt() and 0xFF
+                val luma = if (invert) 255 - y else y
+                pixels[index++] = (0xFF shl 24) or (luma shl 16) or (luma shl 8) or luma
+            }
+        }
+
+        val bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888)
         bitmap.setPixels(pixels, 0, width, 0, 0, width, height)
         return bitmap
     }

app/src/play/java/io/nekohasekai/sfa/vendor/Vendor.kt

@@ -12,6 +12,7 @@ import com.google.android.play.core.install.model.InstallStatus
 import com.google.android.play.core.install.model.UpdateAvailability
 import com.google.mlkit.common.MlKitException
 import io.nekohasekai.sfa.R
+import io.nekohasekai.sfa.ui.profile.QRCodeCropArea
 import io.nekohasekai.sfa.update.UpdateInfo
 import io.nekohasekai.sfa.update.UpdateState
 
@@ -82,9 +83,10 @@ object Vendor : VendorInterface {
     override fun createQRCodeAnalyzer(
         onSuccess: (String) -> Unit,
         onFailure: (Exception) -> Unit,
+        onCropArea: ((QRCodeCropArea?) -> Unit)?,
     ): ImageAnalysis.Analyzer? {
         try {
-            return MLKitQRCodeAnalyzer(onSuccess, onFailure)
+            return MLKitQRCodeAnalyzer(onSuccess, onFailure, onCropArea)
         } catch (exception: Exception) {
             if (exception !is MlKitException || exception.errorCode != MlKitException.UNAVAILABLE) {
                 Log.e(TAG, "failed to create MLKitQRCodeAnalyzer", exception)