From 680b9a1237c4b34ff93893c4efa951e93c5faa3f Mon Sep 17 00:00:00 2001 From: Vadim Date: Sun, 6 Aug 2023 11:52:10 +0200 Subject: [PATCH] Added histogram and separated camera view builder --- .../camera_view/widget_camera_view.dart | 10 +- .../widget_placeholder_camera_view.dart | 0 .../histogram/widget_histogram.dart | 132 ++++++++++++++++++ .../camera_preview/widget_camera_preview.dart | 56 ++++++++ .../widget_container_camera.dart | 26 ++-- 5 files changed, 203 insertions(+), 21 deletions(-) rename lib/screens/metering/components/camera_container/components/{ => camera_preview/components}/camera_view/widget_camera_view.dart (86%) rename lib/screens/metering/components/camera_container/components/{ => camera_preview/components}/camera_view_placeholder/widget_placeholder_camera_view.dart (100%) create mode 100644 lib/screens/metering/components/camera_container/components/camera_preview/components/histogram/widget_histogram.dart create mode 100644 lib/screens/metering/components/camera_container/components/camera_preview/widget_camera_preview.dart diff --git a/lib/screens/metering/components/camera_container/components/camera_view/widget_camera_view.dart b/lib/screens/metering/components/camera_container/components/camera_preview/components/camera_view/widget_camera_view.dart similarity index 86% rename from lib/screens/metering/components/camera_container/components/camera_view/widget_camera_view.dart rename to lib/screens/metering/components/camera_container/components/camera_preview/components/camera_view/widget_camera_view.dart index e443ad1..7c06062 100644 --- a/lib/screens/metering/components/camera_container/components/camera_view/widget_camera_view.dart +++ b/lib/screens/metering/components/camera_container/components/camera_preview/components/camera_view/widget_camera_view.dart @@ -14,10 +14,12 @@ class CameraView extends StatelessWidget { valueListenable: controller, builder: (_, __, ___) => AspectRatio( aspectRatio: _isLandscape(value) ? value.aspectRatio : (1 / value.aspectRatio), - child: RotatedBox( - quarterTurns: _getQuarterTurns(value), - child: controller.buildPreview(), - ), + child: value.isInitialized + ? RotatedBox( + quarterTurns: _getQuarterTurns(value), + child: controller.buildPreview(), + ) + : const SizedBox.shrink(), ), ); } diff --git a/lib/screens/metering/components/camera_container/components/camera_view_placeholder/widget_placeholder_camera_view.dart b/lib/screens/metering/components/camera_container/components/camera_preview/components/camera_view_placeholder/widget_placeholder_camera_view.dart similarity index 100% rename from lib/screens/metering/components/camera_container/components/camera_view_placeholder/widget_placeholder_camera_view.dart rename to lib/screens/metering/components/camera_container/components/camera_preview/components/camera_view_placeholder/widget_placeholder_camera_view.dart diff --git a/lib/screens/metering/components/camera_container/components/camera_preview/components/histogram/widget_histogram.dart b/lib/screens/metering/components/camera_container/components/camera_preview/components/histogram/widget_histogram.dart new file mode 100644 index 0000000..6964e77 --- /dev/null +++ b/lib/screens/metering/components/camera_container/components/camera_preview/components/histogram/widget_histogram.dart @@ -0,0 +1,132 @@ +import 'dart:math'; + +import 'package:camera/camera.dart'; +import 'package:flutter/material.dart'; +import 'package:lightmeter/res/dimens.dart'; + +class CameraHistogram extends StatefulWidget { + final CameraController controller; + + const CameraHistogram({required this.controller, super.key}); + + @override + _CameraHistogramState createState() => _CameraHistogramState(); +} + +class _CameraHistogramState extends State { + List histogramR = List.filled(256, 0); + List histogramG = List.filled(256, 0); + List histogramB = List.filled(256, 0); + + @override + void initState() { + super.initState(); + WidgetsBinding.instance.addPostFrameCallback((_) { + _startImageStream(); + }); + } + + @override + void dispose() { + widget.controller.stopImageStream(); + super.dispose(); + } + + @override + Widget build(BuildContext context) { + return Column( + crossAxisAlignment: CrossAxisAlignment.stretch, + mainAxisSize: MainAxisSize.min, + children: [ + HistogramChannel( + color: Colors.red, + values: histogramR, + ), + const SizedBox(height: Dimens.grid4), + HistogramChannel( + color: Colors.green, + values: histogramG, + ), + const SizedBox(height: Dimens.grid4), + HistogramChannel( + color: Colors.blue, + values: histogramB, + ), + ], + ); + } + + void _startImageStream() { + widget.controller.startImageStream((CameraImage image) { + histogramR = List.filled(256, 0); + histogramG = List.filled(256, 0); + histogramB = List.filled(256, 0); + + final int uvRowStride = image.planes[1].bytesPerRow; + final int uvPixelStride = image.planes[1].bytesPerPixel!; + + for (int x = 0; x < image.width; x++) { + for (int y = 0; y < image.height; y++) { + final int uvIndex = uvPixelStride * (x / 2).floor() + uvRowStride * (y / 2).floor(); + final int index = y * image.width + x; + + final yp = image.planes[0].bytes[index]; + final up = image.planes[1].bytes[uvIndex]; + final vp = image.planes[2].bytes[uvIndex]; + + final r = yp + vp * 1436 / 1024 - 179; + final g = yp - up * 46549 / 131072 + 44 - vp * 93604 / 131072 + 91; + final b = yp + up * 1814 / 1024 - 227; + + histogramR[r.round().clamp(0, 255)]++; + histogramG[g.round().clamp(0, 255)]++; + histogramB[b.round().clamp(0, 255)]++; + } + } + + if (mounted) setState(() {}); + }); + } +} + +class HistogramChannel extends StatelessWidget { + final List values; + final Color color; + + final int _maxOccurences; + + HistogramChannel({ + required this.values, + required this.color, + super.key, + }) : _maxOccurences = values.reduce((value, element) => max(value, element)); + + @override + Widget build(BuildContext context) { + return LayoutBuilder( + builder: (context, constraints) { + final pixelWidth = constraints.maxWidth / values.length; + return Column( + children: [ + SizedBox( + height: Dimens.grid16, + child: Row( + crossAxisAlignment: CrossAxisAlignment.end, + children: values + .map( + (e) => SizedBox( + height: _maxOccurences == 0 ? 0 : Dimens.grid16 * (e / _maxOccurences), + width: pixelWidth, + child: ColoredBox(color: color), + ), + ) + .toList(), + ), + ), + const Divider(), + ], + ); + }, + ); + } +} diff --git a/lib/screens/metering/components/camera_container/components/camera_preview/widget_camera_preview.dart b/lib/screens/metering/components/camera_container/components/camera_preview/widget_camera_preview.dart new file mode 100644 index 0000000..9744909 --- /dev/null +++ b/lib/screens/metering/components/camera_container/components/camera_preview/widget_camera_preview.dart @@ -0,0 +1,56 @@ +import 'package:camera/camera.dart'; +import 'package:flutter/material.dart'; +import 'package:lightmeter/platform_config.dart'; +import 'package:lightmeter/res/dimens.dart'; +import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/components/camera_view/widget_camera_view.dart'; +import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/components/camera_view_placeholder/widget_placeholder_camera_view.dart'; +import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/components/histogram/widget_histogram.dart'; +import 'package:lightmeter/screens/metering/components/camera_container/models/camera_error_type.dart'; + +class CameraPreview extends StatefulWidget { + final CameraController? controller; + final CameraErrorType? error; + + const CameraPreview({this.controller, this.error, super.key}); + + @override + State createState() => _CameraPreviewState(); +} + +class _CameraPreviewState extends State { + @override + Widget build(BuildContext context) { + return AspectRatio( + aspectRatio: PlatformConfig.cameraPreviewAspectRatio, + child: Center( + child: Stack( + children: [ + const CameraViewPlaceholder(error: null), + AnimatedSwitcher( + duration: Dimens.switchDuration, + child: widget.controller != null + ? ValueListenableBuilder( + valueListenable: widget.controller!, + builder: (_, __, ___) => Stack( + alignment: Alignment.bottomCenter, + children: [ + if (widget.controller!.value.isInitialized) + CameraView(controller: widget.controller!), + if (widget.controller!.value.isInitialized) + Positioned( + left: 0, + right: 0, + bottom: Dimens.borderRadiusM, + child: CameraHistogram(controller: widget.controller!), + ), + ], + ), + ) + : CameraViewPlaceholder(error: widget.error), + ), + ], + ), + ), + ); + } +} diff --git a/lib/screens/metering/components/camera_container/widget_container_camera.dart b/lib/screens/metering/components/camera_container/widget_container_camera.dart index 7ac43eb..a8f0a11 100644 --- a/lib/screens/metering/components/camera_container/widget_container_camera.dart +++ b/lib/screens/metering/components/camera_container/widget_container_camera.dart @@ -10,8 +10,7 @@ import 'package:lightmeter/res/dimens.dart'; import 'package:lightmeter/screens/metering/components/camera_container/bloc_container_camera.dart'; import 'package:lightmeter/screens/metering/components/camera_container/components/camera_controls/widget_camera_controls.dart'; import 'package:lightmeter/screens/metering/components/camera_container/components/camera_controls_placeholder/widget_placeholder_camera_controls.dart'; -import 'package:lightmeter/screens/metering/components/camera_container/components/camera_view/widget_camera_view.dart'; -import 'package:lightmeter/screens/metering/components/camera_container/components/camera_view_placeholder/widget_placeholder_camera_view.dart'; +import 'package:lightmeter/screens/metering/components/camera_container/components/camera_preview/widget_camera_preview.dart'; import 'package:lightmeter/screens/metering/components/camera_container/event_container_camera.dart'; import 'package:lightmeter/screens/metering/components/camera_container/models/camera_error_type.dart'; import 'package:lightmeter/screens/metering/components/camera_container/state_container_camera.dart'; @@ -107,20 +106,11 @@ class _CameraViewBuilder extends StatelessWidget { @override Widget build(BuildContext context) { - return AspectRatio( - aspectRatio: PlatformConfig.cameraPreviewAspectRatio, - child: BlocBuilder( - buildWhen: (previous, current) => current is! CameraActiveState, - builder: (context, state) => Center( - child: AnimatedSwitcher( - duration: Dimens.durationM, - child: switch (state) { - CameraInitializedState() => CameraView(controller: state.controller), - CameraErrorState() => CameraViewPlaceholder(error: state.error), - _ => const CameraViewPlaceholder(error: null), - }, - ), - ), + return BlocBuilder( + buildWhen: (previous, current) => current is! CameraActiveState, + builder: (context, state) => CameraPreview( + controller: state is CameraInitializedState ? state.controller : null, + error: state is CameraErrorState ? state.error : null, ), ); } @@ -161,7 +151,9 @@ class _CameraControlsBuilder extends StatelessWidget { }, ); } else { - child = const Column(children: [Expanded(child: SizedBox.shrink())],); + child = const Column( + children: [Expanded(child: SizedBox.shrink())], + ); } return AnimatedSwitcher(