[Windows Phone 7] Mango 密記–使用 PhotoCamera 拍照簡單範例，拍照後儲存至相簿

 

最近在弄 Windows Phone 遇到有關於拍照擷取影像的問題..

參考了一些範例..

因為很多範例因為力求寫的完整，所以我整理一些我用得到的..

此篇目的在於在相機取得影像後，顯示在Rectangle 中，並且可控制對焦，且儲存至相簿中..

 

先看一下XAML Code :

<Grid x:Name="ContentPanel" Grid.Row="0" Margin="0,0,0,0">
         <Rectangle Grid.Row="1"
         x:Name="preview">
             <Rectangle.Fill>
                 <VideoBrush x:Name="previewBrush">
                     <VideoBrush.RelativeTransform>
                         <CompositeTransform x:Name="previewTransform"
                         CenterX=".5"
                         CenterY=".5" />
                     </VideoBrush.RelativeTransform>
                 </VideoBrush>
             </Rectangle.Fill>
         </Rectangle>

        


     </Grid>
     <Button Content="對焦" Grid.Row="1" Height="72" HorizontalAlignment="Left" Margin="12,16,0,0" Name="btnFocus" VerticalAlignment="Top" Width="109" Click="btnFocus_Click" />
     <Button Content="拍照儲存" Height="72" Margin="127,16,133,0" Name="btnTake" VerticalAlignment="Top" Grid.Row="1" Click="btnTake_Click" />

中間那一塊白色的就是Rectangle的部分，將會引入相機的影像..

其中一些說明我就寫在註解裡面

首先 宣告一個 PhotoCamera

private PhotoCamera _photoCamera;

記得要先

using Microsoft.Devices;

之後我們看一下初始化..

protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
{

    base.OnNavigatedFrom(e);

    //CameraType.Primary 為主鏡頭
    //CameraType.FrontFacing 為前鏡頭
    _photoCamera = new Microsoft.Devices.PhotoCamera(CameraType.Primary);

    //初始化事件
    _photoCamera.Initialized += new EventHandler<CameraOperationCompletedEventArgs>(_photoCamera_Initialized);

    //當呼叫CaptureImage 擷取影像時觸發事件
    _photoCamera.CaptureImageAvailable += new EventHandler<ContentReadyEventArgs>(_photoCamera_CaptureImageAvailable);

    previewBrush.SetSource(_photoCamera);
}

為什麼不寫在Ctor 裡面呢? 請參考此篇 [Windows Phone 7] Mango 密記–關於 OnNavigatedTo 跟 Constructor 一些不同..

初始化  _photoCamera_Initialized :

void _photoCamera_Initialized(object sender, CameraOperationCompletedEventArgs e)
{
    if (e.Succeeded)
    {
        this.Dispatcher.BeginInvoke(delegate()
        {
            MessageBox.Show("初始化成功 ");
        });
    }

    Dispatcher.BeginInvoke(() =>
    {
        previewTransform.Rotation = _photoCamera.Orientation;
    });

    _photoCamera.FlashMode = FlashMode.Auto;
}

其中 previewTransform.Rotation = _photoCamera.Orientation;

主要目的是讓您的影像，不會是向右轉90的…

擷取影像後的觸發事件

void _photoCamera_CaptureImageAvailable(object sender, ContentReadyEventArgs e)
{

    MediaLibrary library = new MediaLibrary();

    string fileName = Guid.NewGuid().ToString() + ".jpg";

    try
    {
        Deployment.Current.Dispatcher.BeginInvoke(delegate()
        {
            MessageBox.Show("進行儲存");
        });

        //儲存至 相簿
        library.SavePictureToCameraRoll(fileName, e.ImageStream);
      
    }
    catch (Exception ex)
    {
        MessageBox.Show("Error:" + ex.Message);
    }

}

MediaLibrary  要使用必須先

using Microsoft.Xna.Framework.Media;

之後就可以呼叫 CaptureImage()  進行拍照

private void btnTake_Click(object sender, RoutedEventArgs e)
{
           //拍照
           _photoCamera.CaptureImage();
}

因為相機支援對焦 所以 可以呼叫 Focus() 進行對焦..

不然都會糊糊的..

private void btnFocus_Click(object sender, RoutedEventArgs e)
{
    //對焦
    _photoCamera.Focus();
}

參考文件:

拍照:
http://msdn.microsoft.com/en-us/library/hh202956%28v=VS.92%29.aspx

Flash mode:
http://msdn.microsoft.com/zh-tw/library/hh202949(v=vs.92).aspx
CaptureImageAvailable Event:
http://msdn.microsoft.com/zh-tw/library/microsoft.devices.photocamera.captureimageavailable(v=vs.92).aspx

下面有範例就自行下載測試..