improve example

shirne · Nov 6, 2022 · b3b934f · b3b934f
1 parent 20dcd85
commit b3b934f
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Showing 4 changed files with 56 additions and 15 deletions.
diff --git a/example/lib/models/utils.dart b/example/lib/models/utils.dart
@@ -118,13 +118,25 @@ int getColorFromByte(List<int> byte, int index, {bool isLog = false}) {
   );
 }
 
+int getLuminanceSourcePixel(List<int> byte, int index) {
+  if (byte.length <= index + 3) {
+    return 0xff;
+  }
+  final r = byte[index] & 0xff; // red
+  final g2 = (byte[index + 1] << 1) & 0x1fe; // 2 * green
+  final b = byte[index + 2]; // blue
+  // Calculate green-favouring average cheaply
+  return ((r + g2 + b) ~/ 4);
+}
+
 List<Result>? decodeImage(IsoMessage message) {
-  final pixels = List<int>.generate(
-    message.width * message.height,
-    (index) => getColorFromByte(message.byteData, index * 4),
-  );
+  final pixels = Uint8List(message.width * message.height);
+  for (int i = 0; i < pixels.length; i++) {
+    pixels[i] = getLuminanceSourcePixel(message.byteData, i * 4);
+  }
+  print(pixels);
 
-  final imageSource = RGBLuminanceSource(
+  final imageSource = RGBLuminanceSource.orig(
     message.width,
     message.height,
     pixels,

diff --git a/example/lib/scanner/camera.dart b/example/lib/scanner/camera.dart
@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:ui' as ui;
 
 import 'package:buffer_image/buffer_image.dart';
 import 'package:camera/camera.dart';
@@ -47,6 +48,8 @@ class _CameraPageState extends State<CameraPage> {
           return;
         }
 
+        _controller!.setFlashMode(_flashMode);
+
         setState(() {
           detectedCamera = true;
         });
@@ -58,25 +61,29 @@ class _CameraPageState extends State<CameraPage> {
     }
   }
 
+  BufferImage? image;
   Future<void> onCameraView() async {
-    if (isDetecting) return;
+    if (isDetecting || !mounted) return;
     setState(() {
       isDetecting = true;
     });
     XFile pic = await _controller!.takePicture();
 
     Uint8List data = await pic.readAsBytes();
-    BufferImage? image = await BufferImage.fromFile(data);
+    image = await BufferImage.fromFile(data);
+    if (!mounted) return;
     if (image != null) {
-      if (image.width > 1000) {
-        image.scaleDown(image.width / 800);
-      }
+      setState(() {});
 
-      var results =
-          await decodeImageInIsolate(image.buffer, image.width, image.height);
+      var results = await decodeImageInIsolate(
+        image!.buffer,
+        image!.width,
+        image!.height,
+      );
       if (!mounted) return;
       setState(() {
         isDetecting = false;
+        image = null;
       });
       if (results != null) {
         Navigator.of(context).pushNamed('/result', arguments: results);
@@ -88,6 +95,7 @@ class _CameraPageState extends State<CameraPage> {
       }
     } else {
       setState(() {
+        image = null;
         isDetecting = false;
       });
       print('can\'t take picture from camera');
@@ -142,6 +150,25 @@ class _CameraPageState extends State<CameraPage> {
                 _controller!,
                 child: Stack(
                   children: [
+                    if (image != null)
+                      Positioned(
+                        left: 0,
+                        top: 0,
+                        right: 0,
+                        bottom: 0,
+                        child: FutureBuilder<ui.Image>(
+                          future: image!.getImage(),
+                          builder: (context, snapshot) {
+                            if (!snapshot.hasData) {
+                              return const SizedBox.shrink();
+                            }
+                            return RawImage(
+                              image: snapshot.data!,
+                              fit: BoxFit.fill,
+                            );
+                          },
+                        ),
+                      ),
                     Align(
                       alignment: const Alignment(0, 0.7),
                       child: CupertinoIconButton(

diff --git a/example/lib/scanner/camera_stream.dart b/example/lib/scanner/camera_stream.dart
@@ -75,7 +75,7 @@ class _CameraStreamPageState extends State<CameraStreamPage> {
 
   bool _isStart = false;
   Future<void> start() async {
-    if (_isStart) return;
+    if (_isStart || !mounted) return;
     await _controller!.startImageStream(tryDecodeImage);
     _isStart = true;
   }
@@ -87,19 +87,21 @@ class _CameraStreamPageState extends State<CameraStreamPage> {
   }
 
   Future<void> tryDecodeImage(CameraImage image) async {
-    if (isDetecting) return;
+    if (isDetecting || !mounted) return;
     await stop();
     setState(() {
       isDetecting = true;
     });
 
     try {
       final results = await _isoController.setPlanes(image.planes);
+      if (!mounted) return;
       setState(() {
         isDetecting = false;
       });
       Navigator.of(context).pushNamed('/result', arguments: results);
     } catch (_) {
+      if (!mounted) return;
       setState(() {
         isDetecting = false;
       });

diff --git a/example/pubspec.lock b/example/pubspec.lock
@@ -370,7 +370,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "0.7.3"
+    version: "0.8.1"
 sdks:
   dart: ">=2.17.0 <3.0.0"
   flutter: ">=3.0.5"