WP8出来好一段时间了，新出的AudioVideoCaptureDevice类自定义功能比WP7的CaptureSource强大的多，但网上比较全面的中文实例还比较少，分享一个最近做的小实例给大家参考。
一、实现的功能
1、实现视频和音频的采集并保存
2、允许切换前后摄像头
3、录像过程中可以随时截图
4、录像后视频播放
二、需要的权限
1、需要访问前后摄像头的权限（ID_CAP_ISV_CAMERA）
2、需要访问麦克风的权限（ID_CAP_MICROPHONE)
三 、UI部分
1、使用一个Rectangle控件实时显示摄像头采集到的画面
2、使用一个Image控件来显示视频截图
3、使用一个MediaElement控件来播放录制好的视频
4、使用一个HyperLinkButton控件来切换摄像头
<Canvas x:Name="LayoutRoot" Background="Transparent">
<!--Camera viewfinder >-->
<Rectangle x:Name="Re_video" Width="640" Height="480">
<Rectangle.Fill>
<VideoBrush x:Name="TheVideoBrush"></VideoBrush>
</Rectangle.Fill>
</Rectangle>
<MediaElement
x:Name="VideoPlayer"
Width="480"
Height="640"
AutoPlay="True"
RenderTransformOrigin="0.5, 0.5"
VerticalAlignment="Center"
HorizontalAlignment="Center"
Stretch="Fill"
Canvas.Left="0"/>
<Image Name="imgCapture" Width="320" Height="240" Margin="20 0 0 0" />
<Grid Margin="20,10" Width="450">
<HyperlinkButton Width="50" x:Name="hyper_changes" Click="hyper_changes_Click" HorizontalAlignment="Right">
<HyperlinkButton.Template>
<ControlTemplate>
<Image Source="/Images/Camera/changes.png" />
</ControlTemplate>
</HyperlinkButton.Template>
</HyperlinkButton>
</Grid>
</Canvas>
四、代码部分
1、定义基础变量
//目录
private string m_path = "Vedio";
//视频文件名
private string m_filename = string.Empty;
//用于设置摄像头旋转的角度
RotateTransform rt1 = new RotateTransform();
//用于设置使用前置还是后置的摄像头
CameraSensorLocation sensorLocation = CameraSensorLocation.Front;
//随机访问数据流
private Windows.Storage.Streams.IRandomAccessStream m_iRandomAccessStream;
//捕获视频设备对象
private Windows.Phone.Media.Capture.AudioVideoCaptureDevice m_captureDevice;
2、初始化录像设备
/// <summary> /// 初始化捕获设备， /// </summary> private async void Init() { try { if (m_captureDevice != null) { m_captureDevice.Dispose(); m_captureDevice = null; } //获取视频捕获设备 m_captureDevice = await AudioVideoCaptureDevice.OpenAsync(sensorLocation, new Windows.Foundation.Size(640, 480)); int sensorOrientation = (Int32)this.m_captureDevice.SensorRotationInDegrees; if (sensorLocation == CameraSensorLocation.Back) { rt1.CenterX = 230; rt1.CenterY = 240; rt1.Angle = 90; Re_video.RenderTransform = rt1; } else { rt1.CenterX = 320; rt1.CenterY = 330; rt1.Angle = 270; Re_video.RenderTransform = rt1; } m_captureDevice.SetProperty(KnownCameraGeneralProperties.EncodeWithOrientation, sensorLocation == CameraSensorLocation.Back ? 90 : 270); //m_captureDevice.SetProperty(KnownCameraAudioVideoProperties.VideoFrameRate, 20); m_captureDevice.SetProperty(KnownCameraAudioVideoProperties.UnmuteAudioWhileRecording, true); m_captureDevice.VideoEncodingFormat = CameraCaptureVideoFormat.H264; TheVideoBrush.SetSource(m_captureDevice); //设置视频数据格式 } catch (Exception e) { throw e; } }
注意：
1)、KnownCameraGeneralProperties.EncodeWithOrientation 可以控制前后摄像头旋转的角度， 默认情况下WP获取的视频都是倒着显示的
2)、KnownCameraAudioVideoProperties.UnmuteAudioWhileRecording 是让视频在录制时取消静音，默认情况下是静音的
3)、CameraCaptureVideoFormat.H264; 使用H264编码方式
3、开始录制视频
//开始录制
private async void StartRecord()
{
m_filename = Guid.NewGuid().ToString() + ".mp4";
try
{
StorageFile file = null;
StorageFolder folder = ApplicationData.Current.LocalFolder;
using (IsolatedStorageFile isolatedStorageFile = IsolatedStorageFile.GetUserStoreForApplication())
{
//不存在目录，则创建
if (!isolatedStorageFile.DirectoryExists(m_path))
{
isolatedStorageFile.CreateDirectory(m_path);
}
}
folder = await folder.GetFolderAsync(m_path);
m_iRandomAccessStream = null;
//创建视频文件
file = await folder.CreateFileAsync(m_filename, CreationCollisionOption.ReplaceExisting);
m_iRandomAccessStream = await file.OpenAsync(FileAccessMode.ReadWrite);
//开始捕获视频数据并写到随机流中
await m_captureDevice.StartRecordingToStreamAsync(m_iRandomAccessStream);
}
catch (Exception ex)
{
throw ex;
}
}
4、录制过程中实现截图功能
/// <summary> /// 截取视频图像 /// </summary> private void GetPreview() { WriteableBitmap wBitmap = new WriteableBitmap(640, 480); wBitmap.Render(Re_video, new MatrixTransform());//截取视频 wBitmap.Invalidate(); imgCapture.Source = wBitmap; }
注意：这段代码的思路其实是截取Rectangle控件的UI界面
5、停止录制视频
//停止录制 private async void StopRecord() { try { await m_captureDevice.StopRecordingAsync(); m_iRandomAccessStream.Dispose(); } catch (Exception ex) { throw ex; } }
6、播放录制好的视频
/// <summary>
/// 播放录制的视频
/// </summary>
private void PlayVideo()
{
string path = m_path + "/" + m_filename;
using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
{
using (IsolatedStorageFileStream fileStream = myIsolatedStorage.OpenFile(path, FileMode.Open, FileAccess.Read))
{
VideoPlayer.SetSource(fileStream);
fileStream.Dispose();
fileStream.Close();
}
}
}
7、切换前后摄像头
/// <summary> /// 切换前后摄像头 /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void hyper_changes_Click(object sender, System.Windows.RoutedEventArgs e) { if (sensorLocation == CameraSensorLocation.Front) sensorLocation = CameraSensorLocation.Back; else sensorLocation = CameraSensorLocation.Front; Init(); }
至此，大致功能全部实现了， 当然还需要处理一些按钮事件， 这些直接看附件吧：
http://share.weiyun.com/d89188c5490e6bf95c7f7aa08c0f81bc
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