android implementation

casvanluijtelaar
Commit de533d51b75f833bf852d5c5fef1e1c21fb359ba de533d51 1 parent 54239631
Showing 5 changed files with 220 additions and 1 deletions
android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScanner.kt
example/lib/barcode_scanner_window.dart
example/lib/main.dart
lib/src/mobile_scanner.dart
lib/src/mobile_scanner_controller.dart
--- a/android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScanner.kt
View file @de533d5
+++ b/android/src/main/kotlin/dev/steenbakker/mobile_scanner/MobileScanner.kt
View file @de533d5
@@ -4,9 +4,11 @@ import android.Manifest
 import android.app.Activity
 import android.content.pm.PackageManager
 import android.graphics.Point
+import android.graphics.Rect
 import android.net.Uri
 import android.util.Log
 import android.util.Size
+import android.media.Image
 import android.view.Surface
 import androidx.annotation.NonNull
 import androidx.camera.core.*
@@ -18,6 +20,7 @@ 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 com.google.mlkit.vision.common.InputImage.IMAGE_FORMAT_NV21
 import io.flutter.plugin.common.EventChannel
 import io.flutter.plugin.common.MethodCall
 import io.flutter.plugin.common.MethodChannel
@@ -40,6 +43,7 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
     private var camera: Camera? = null
     private var preview: Preview? = null
     private var textureEntry: TextureRegistry.SurfaceTextureEntry? = null
+    private var scanWindow: Rect? = null;
 //    @AnalyzeMode
 //    private var analyzeMode: Int = AnalyzeMode.NONE
@@ -99,7 +103,20 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
 //        when (analyzeMode) {
 //            AnalyzeMode.BARCODE -> {
                 val mediaImage = imageProxy.image ?: return@Analyzer
-                val inputImage = InputImage.fromMediaImage(mediaImage, imageProxy.imageInfo.rotationDegrees)
+                var inputImage: InputImage?;
+
+                if(scanWindow != null) {
+                    val croppedImage = croppedNV21(mediaImage, scanWindow!!)
+                    inputImage =  InputImage.fromByteArray(
+                        croppedImage, 
+                        scanWindow!!.width(),
+                        scanWindow!!.height(),
+                        imageProxy.imageInfo.rotationDegrees,
+                        IMAGE_FORMAT_NV21,
+                        )
+                } else {
+                    inputImage = InputImage.fromMediaImage(mediaImage, imageProxy.imageInfo.rotationDegrees)
+                }
                 scanner.process(inputImage)
                         .addOnSuccessListener { barcodes ->
@@ -115,6 +132,50 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
 //        }
     }
+     private fun croppedNV21(mediaImage: Image, cropRect: Rect): ByteArray {
+        val yBuffer = mediaImage.planes[0].buffer // Y
+        val vuBuffer = mediaImage.planes[2].buffer // VU
+
+        val ySize = yBuffer.remaining()
+        val vuSize = vuBuffer.remaining()
+
+        val nv21 = ByteArray(ySize + vuSize)
+
+        yBuffer.get(nv21, 0, ySize)
+        vuBuffer.get(nv21, ySize, vuSize)
+
+        return cropByteArray(nv21, mediaImage.width, mediaImage.height, cropRect)
+    }
+
+    private fun cropByteArray(src: ByteArray, width: Int, height: Int, cropRect: Rect, ): ByteArray {
+        val x = cropRect.left * 2 / 2
+        val y = cropRect.top * 2 / 2
+        val w = cropRect.width() * 2 / 2
+        val h = cropRect.height() * 2 / 2
+        val yUnit = w * h
+        val uv = yUnit / 2
+        val nData = ByteArray(yUnit + uv)
+        val uvIndexDst = w * h - y / 2 * w
+        val uvIndexSrc = width * height + x
+        var srcPos0 = y * width
+        var destPos0 = 0
+        var uvSrcPos0 = uvIndexSrc
+        var uvDestPos0 = uvIndexDst
+        for (i in y until y + h) {
+            System.arraycopy(src, srcPos0 + x, nData, destPos0, w) //y memory block copy
+            srcPos0 += width
+            destPos0 += w
+            if (i and 1 == 0) {
+                System.arraycopy(src, uvSrcPos0, nData, uvDestPos0, w) //uv memory block copy
+                uvSrcPos0 += width
+                uvDestPos0 += w
+            }
+        }
+        return nData
+    }
+
+
+
     private var scanner = BarcodeScanning.getClient()
@@ -134,6 +195,9 @@ class MobileScanner(private val activity: Activity, private val textureRegistry:
             val torch: Boolean = call.argument<Boolean>("torch") ?: false
             val formats: List<Int>? = call.argument<List<Int>>("formats")
+            val scanWindowData: List<Int>? = call.argument("scanWindow")
+            if(scanWindowData != null) scanWindow = Rect(scanWindowData!![0], scanWindowData!![1], scanWindowData!![2], scanWindowData!![3])
+
             if (formats != null) {
                 val formatsList: MutableList<Int> = mutableListOf()
                 for (index in formats) {
--- a/example/lib/barcode_scanner_window.dart 0 → 100644
View file @de533d5
+++ b/example/lib/barcode_scanner_window.dart 0 → 100644
View file @de533d5
+import 'dart:ui';
+
+import 'package:flutter/material.dart';
+import 'package:mobile_scanner/mobile_scanner.dart';
+
+class BarcodeScannerWithScanWindow extends StatefulWidget {
+  const BarcodeScannerWithScanWindow({Key? key}) : super(key: key);
+
+  @override
+  _BarcodeScannerWithScanWindowState createState() =>
+      _BarcodeScannerWithScanWindowState();
+}
+
+class _BarcodeScannerWithScanWindowState
+    extends State<BarcodeScannerWithScanWindow>
+    with SingleTickerProviderStateMixin {
+  String? barcode;
+
+  late Rect scanWindow;
+  late MobileScannerController controller;
+
+  @override
+  void initState() {
+    super.initState();
+
+    final screenWidth =
+        window.physicalSize.shortestSide / window.devicePixelRatio;
+    final screenHeight =
+        window.physicalSize.longestSide / window.devicePixelRatio;
+
+    scanWindow = Rect.fromCenter(
+      center: Offset(screenWidth / 2, screenHeight / 2),
+      width: 200,
+      height: 200,
+    );
+
+    controller = MobileScannerController(
+      torchEnabled: true,
+      scanWindow: scanWindow,
+    );
+  }
+
+  bool isStarted = true;
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      backgroundColor: Colors.black,
+      body: Builder(
+        builder: (context) {
+          return Stack(
+            children: [
+              MobileScanner(
+                fit: BoxFit.contain,
+                controller: controller,
+                onDetect: (barcode, args) {
+                  setState(() {
+                    this.barcode = barcode.rawValue;
+                  });
+                },
+              ),
+              CustomPaint(
+                painter: ScannerOverlay(scanWindow),
+              ),
+              Align(
+                alignment: Alignment.bottomCenter,
+                child: Container(
+                  alignment: Alignment.bottomCenter,
+                  height: 100,
+                  color: Colors.black.withOpacity(0.4),
+                  child: Row(
+                    mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+                    children: [
+                      Center(
+                        child: SizedBox(
+                          width: MediaQuery.of(context).size.width - 120,
+                          height: 50,
+                          child: FittedBox(
+                            child: Text(
+                              barcode ?? 'Scan something!',
+                              overflow: TextOverflow.fade,
+                              style: Theme.of(context)
+                                  .textTheme
+                                  .headline4!
+                                  .copyWith(color: Colors.white),
+                            ),
+                          ),
+                        ),
+                      ),
+                    ],
+                  ),
+                ),
+              ),
+            ],
+          );
+        },
+      ),
+    );
+  }
+}
+
+class ScannerOverlay extends CustomPainter {
+  ScannerOverlay(this.scanWindow);
+
+  final Rect scanWindow;
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    final backgroundPath = Path()..addRect(Rect.largest);
+    final cutoutPath = Path()..addRect(scanWindow);
+
+    final backgroundPaint = Paint()
+      ..color = Colors.black.withOpacity(0.5)
+      ..style = PaintingStyle.fill
+      ..blendMode = BlendMode.dstOut;
+
+    final backgroundWithCutout = Path.combine(
+      PathOperation.difference,
+      backgroundPath,
+      cutoutPath,
+    );
+    canvas.drawPath(backgroundWithCutout, backgroundPaint);
+  }
+
+  @override
+  bool shouldRepaint(covariant CustomPainter oldDelegate) {
+    return false;
+  }
+}
--- a/example/lib/main.dart
View file @de533d5
+++ b/example/lib/main.dart
View file @de533d5
 import 'package:flutter/material.dart';
 import 'package:mobile_scanner_example/barcode_scanner_controller.dart';
+import 'package:mobile_scanner_example/barcode_scanner_window.dart';
 import 'package:mobile_scanner_example/barcode_scanner_without_controller.dart';
+
 void main() => runApp(const MaterialApp(home: MyHome()));
 class MyHome extends StatelessWidget {
@@ -27,6 +29,17 @@ class MyHome extends StatelessWidget {
               },
               child: const Text('MobileScanner with Controller'),
             ),
+
+            ElevatedButton(
+              onPressed: () {
+                Navigator.of(context).push(
+                  MaterialPageRoute(
+                    builder: (context) => const BarcodeScannerWithScanWindow(),
+                  ),
+                );
+              },
+              child: const Text('MobileScanner with ScanWindow'),
+            ),
             ElevatedButton(
               onPressed: () {
                 Navigator.of(context).push(
--- a/lib/src/mobile_scanner.dart
View file @de533d5
+++ b/lib/src/mobile_scanner.dart
View file @de533d5
@@ -27,6 +27,7 @@ class MobileScanner extends StatefulWidget {
   /// Set to false if you don't want duplicate scans.
   final bool allowDuplicates;
+
   /// Create a [MobileScanner] with a [controller], the [controller] must has been initialized.
   const MobileScanner({
     Key? key,
--- a/lib/src/mobile_scanner_controller.dart
View file @de533d5
+++ b/lib/src/mobile_scanner_controller.dart
View file @de533d5
@@ -49,6 +49,9 @@ class MobileScannerController {
   /// WARNING: On iOS, only 1 format is supported.
   final List<BarcodeFormat>? formats;
+  /// can be used to limit the scan area to a portion of the screen
+  final Rect? scanWindow;
+
   CameraFacing facing;
   bool hasTorch = false;
   late StreamController<Barcode> barcodesController;
@@ -60,6 +63,7 @@ class MobileScannerController {
     this.ratio,
     this.torchEnabled,
     this.formats,
+    this.scanWindow,
   }) {
     // In case a new instance is created before calling dispose()
     if (_controllerHashcode != null) {
@@ -156,6 +160,14 @@ class MobileScannerController {
     // Set the starting arguments for the camera
     final Map arguments = {};
     arguments['facing'] = facing.index;
+    if (scanWindow != null) {
+      arguments['scanWindow'] = [
+        scanWindow!.left,
+        scanWindow!.top,
+        scanWindow!.right,
+        scanWindow!.bottom,
+      ];
+    }
     if (ratio != null) arguments['ratio'] = ratio;
     if (torchEnabled != null) arguments['torch'] = torchEnabled;