Overview

• File: lib/views/hvc_camera_page.dart

The hvc_camera_page.dart file implements the camera functionality of the HVC XR application. It provides a comprehensive camera interface with features for video recording, image capture, torch control, camera switching, and audio output selection. The page is designed to work with RealWear devices and supports both video and image capture with proper storage management.

Class Structure

class HvcCameraPage extends StatefulWidget {
  static const String routeName = '/HvcCameraPage';
  const HvcCameraPage({Key? key}) : super(key: key);

  @override
  _HvcCameraPageState createState() => _HvcCameraPageState();
}

class _HvcCameraPageState extends State<HvcCameraPage> {
  // State variables and methods
}

Dependencies

import 'dart:async';
import 'dart:core';
import 'dart:io';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:get/get_rx/src/rx_types/rx_types.dart';
import 'package:hippo_web_rtc/hippo_web_rtc.dart';
import 'package:path_provider/path_provider.dart';
import 'package:uuid/uuid.dart';
// Additional imports for controllers and utilities

Key Components

State Variables

MediaStream? _localStream;
final _localRenderer = RTCVideoRenderer();
bool _inCalling = false;
MediaRecorder? _mediaRecorder;
bool get _isRec => _mediaRecorder != null;
List<MediaDeviceInfo>? _mediaDevicesList;
RxString timeString = ''.obs;

Controllers

final MediaController mediaController = Get.find();
final RealTimeController realTimeController = Get.find();

Camera Initialization

Renderer Setup

void initRenderers() async {
  await _localRenderer.initialize();
}

Media Stream Configuration

void _makeCall() async {
  final mediaConstraints = <String, dynamic>{
    'audio': true,
    'video': {
      'mandatory': {
        'minWidth': '640',
        'minHeight': '480',
        'minFrameRate': '30',
      },
      'facingMode': 'environment',
      'optional': [],
    }
  };

  try {
    var stream = await navigator.mediaDevices.getUserMedia(mediaConstraints);
    _mediaDevicesList = await navigator.mediaDevices.enumerateDevices();
    _localStream = stream;
    _localRenderer.srcObject = _localStream;
  } catch (e) {
    print(e.toString());
  }
}

Recording Functionality

Video Recording

void _startRecording() async {
  if (_localStream == null) throw Exception('Stream is not initialized');
  if (Platform.isIOS) {
    print('Recording is not available on iOS');
    return;
  }

  final dir = await getExternalStorageDirectory() ??
      await getApplicationDocumentsDirectory();
  _fileName = 'xr_vid_${DateTime.now().millisecondsSinceEpoch}.mp4';
  _filePath = '${dir.path}/hvc_xr/$_fileName';

  _mediaRecorder = MediaRecorder();
  setState(() {});

  final videoTrack = _localStream!
      .getVideoTracks()
      .firstWhere((track) => track.kind == 'video');
  await _mediaRecorder!.start(
    _filePath,
    videoTrack: videoTrack,
  );
  recTimer = Timer.periodic(const Duration(seconds: 1), (timer) {
    timeString.value = Duration(seconds: timer.tick).toFormattedString();
  });
}

Stop Recording

void _stopRecording() async {
  await _mediaRecorder?.stop().whenComplete(() async =>
      await mediaController.saveFileRecord(
          _sessionDate, _filePath, _fileName, null, 'video', _sessionId));
  recTimer.cancel();
  HlkDialog.showSuccessSnackBar('video recorded');
  await Future.delayed(
      const Duration(seconds: 2), () => timeString.value = '');
  setState(() {
    _mediaRecorder = null;
  });
}

Camera Controls

Torch Control

void _toggleTorch() async {
  if (_localStream == null) throw Exception('Stream is not initialized');

  final videoTrack = _localStream!
      .getVideoTracks()
      .firstWhere((track) => track.kind == 'video');
  final has = await videoTrack.hasTorch();
  if (has) {
    await videoTrack.setTorch(realTimeController.isTouchOn.value);
  }
}

Camera Switching

void _toggleCamera() async {
  if (_localStream == null) throw Exception('Stream is not initialized');

  final videoTrack = _localStream!
      .getVideoTracks()
      .firstWhere((track) => track.kind == 'video');
  await Helper.switchCamera(videoTrack);
}

Image Capture

void _captureFrame() async {
  if (_localStream == null) throw Exception('Stream is not initialized');

  final videoTrack = _localStream!
      .getVideoTracks()
      .firstWhere((track) => track.kind == 'video');

  final frame = await videoTrack.captureFrame();
  final byteArray = frame.asUint8List();
  _fileName = 'xr_img_${DateTime.now().millisecondsSinceEpoch}.jpg';

  var dir = await getExternalStorageDirectory();
  dir ??= await getApplicationDocumentsDirectory();

  File imgFile = File(path.join(dir.path, 'hvc_xr', _fileName));
  imgFile.createSync(recursive: true);

  await showDialog(
      context: context,
      builder: (context) => AlertDialog(
            content: Image.memory(byteArray, height: 720, width: 1280),
            actions: <Widget>[
              TextButton(
                onPressed: Navigator.of(context, rootNavigator: true).pop,
                child: const Text('OK'),
              )
            ],
          ));

  byteArrayToFile(byteArray, imgFile, isAsync: true);

  await mediaController.saveFileRecord(
      _sessionDate, imgFile.path, _fileName, null, 'image', _sessionId);
}

UI Implementation

Camera View

Center(
  child: Container(
    margin: const EdgeInsets.fromLTRB(0.0, 0.0, 0.0, 0.0),
    width: MediaQuery.of(context).size.width,
    height: MediaQuery.of(context).size.height,
    child: RTCVideoView(
      _localRenderer,
      mirror: true,
      objectFit: RTCVideoViewObjectFit.RTCVideoViewObjectFitCover,
    ),
  ),
)

Control Buttons

persistentFooterButtons: [
  Obx(
    () => IconButton(
      icon: Icon(
        realTimeController.isTouchOn.value
            ? Icons.flash_off
            : Icons.flash_on,
        color: Colors.white,
      ),
      onPressed: _toggleTorch,
      tooltip: realTimeController.isTouchOn.value ? 'flash off' : 'flash on',
    ),
  ),
  IconButton(
    icon: const Icon(Icons.switch_video, color: Colors.white),
    onPressed: _toggleCamera,
    tooltip: 'switch camera',
  ),
  IconButton(
    icon: const Icon(Icons.camera, color: kAppColorWhite),
    onPressed: _captureFrame,
    tooltip: 'take picture',
  ),
  IconButton(
    icon: Icon(
      _isRec ? Icons.stop : Icons.fiber_manual_record,
      color: _isRec ? kAppColorBlue : kAppColorWhite,
    ),
    onPressed: _isRec ? _stopRecording : _startRecording,
    tooltip: _isRec ? 'stop recording' : 'start recording',
  ),
  // Audio output selection menu
]

Dependencies

• hippo_web_rtc: WebRTC implementation
• get: State management
• path_provider: File system access
• uuid: Unique identifier generation
• flutter/material.dart: UI components

Styling

• Uses consistent color scheme
• Implements responsive design
• Provides clear visual feedback
• Maintains consistent button styling
• Uses appropriate icons for actions