通过前置摄像头录制视频-WP8-C# [英] record video by front-camera - WP8 - C#

问题描述

我的Windows Phone应用需要记录来自前置摄像头的视频，然后通过网络服务将其发送到服务器.

My windows phone app needs to record a video from front-camera and send it to the server through a webservice.

在这里，当我尝试从front-camera录制视频时，我得到了mirror inverted video.意味着前置摄像头记录了180度旋转的视频.

Here while I'm trying to record video from front-camera, I'm getting mirror inverted video. Means front-camera records 180 degree rotated video.

我认为可能唯一的解决方案是将录制的视频流向后旋转180度.

what i think probably the only solution of it is to rotate the recorded video stream to 180 degree back.

问题:

• 还有其他解决方案可以通过前置摄像头在wp8中录制正确的视频吗?
• 如果没有，如何将视频流旋转180度?任何c# API都可以做到..?

• is there any other solution to record proper video by front-camera in wp8?
• if not, how to rotate the video stream 180 degree? any c# API to do it..?

这是我正在使用的代码:

Here is code that I'm using:

VideoBrush

XAML code for VideoBrush

    <Canvas x:Name="CanvasLayoutRoot" RenderTransformOrigin="0.5 0.5"
            Width="{Binding ActualHeight, ElementName=LayoutRoot}"
            Height="{Binding ActualWidth, ElementName=LayoutRoot}"
            Margin="-160 0 0 0">
        <!--Background="Transparent"-->

        <Canvas.Background>
            <VideoBrush x:Name="videoBrush" />
        </Canvas.Background>
        <Canvas.RenderTransform>
            <RotateTransform x:Name="rt" />
        </Canvas.RenderTransform>

    </Canvas>

初始化相机

    public async void InitializeVideoRecorder()
    {
        try
        {
            if (videoCapture == null)
            {
                // below line of code will detect if "Front Camera" is available or not
                // if availble, then open it or it will open "Back Camera"

                videoCapture = await AudioVideoCaptureDevice.OpenAsync(
                    AudioVideoCaptureDevice.AvailableSensorLocations.Contains(CameraSensorLocation.Front) ? CameraSensorLocation.Front : CameraSensorLocation.Back,
                    new Windows.Foundation.Size(640, 480));

                videoCapture.RecordingFailed += videoCapture_RecordingFailed;

                videoCapture.SetProperty(KnownCameraGeneralProperties.EncodeWithOrientation, videoCapture.SensorRotationInDegrees);

                // Initialize the camera if it exists on the phone.
                if (videoCapture != null)
                {
                    videoBrush.SetSource(videoCapture);
                    if (!AudioVideoCaptureDevice.AvailableSensorLocations.Contains(CameraSensorLocation.Front))
                    {
                        rt.Angle = videoCapture.SensorRotationInDegrees;
                    }
                    else
                    {
                        rt.Angle = -(videoCapture.SensorRotationInDegrees);
                    }
                }
                else
                {
                    MessageBox.Show("Unable to load Camera. Please try again later.", App.appName, MessageBoxButton.OK);
                    NavigationService.GoBack();
                }
            }
        }
        catch (Exception ex)
        {
            (new WebServices()).catchExceptions(ex);
            NavigationService.GoBack();
        }
    }

启动VideoCapture

    private async Task StartVideoRecording()
    {
        try
        {
            // Gets the application data folder
            StorageFolder applicationFolder = ApplicationData.Current.LocalFolder;
            StorageFolder transfersFolder = await (await applicationFolder.GetFolderAsync("Shared")).GetFolderAsync("Transfers");

            // Create the file specified in the application data folder
            videoFileName = selectedQue.response.template_id + "_" + selectedQue.response.id + "_" + selectedQue.response.invite_id +".mp4";
            StorageFile storageFile = await transfersFolder.CreateFileAsync(videoFileName, CreationCollisionOption.ReplaceExisting);

            // Open a file stream, ready to write video data
            randomAccessStream = await storageFile.OpenAsync(FileAccessMode.ReadWrite);

            // Video recording to the specified stream
            await videoCapture.StartRecordingToStreamAsync(randomAccessStream);
            isRecordingStarted = true;

            //timer = "0:00";
            tbTimer.Text = "0:00";
            dt.Start();
        }
        catch (Exception ex)
        {
            (new WebServices()).catchExceptions(ex);
        }
    }

推荐答案

最后，经过24小时的以下解决方案，我解决了我的问题.

Finally i solved my problem after 24 hours of efforts with below solution.

下面是通过旋转视频引起问题的代码行.

The line of code that causing issue by rotating video was below.

videoCapture.SetProperty(KnownCameraGeneralProperties.EncodeWithOrientation, videoCapture.SensorRotationInDegrees);

此处videoCapture是AudioVideoCaptureDevice的对象

here videoCapture is object of AudioVideoCaptureDevice

在使用前置摄像头时，我们需要反转cameraSensor的旋转.

While using front camera, we need to invert the rotation of cameraSensor.

因此，我在代码的videoCapture.SetProperty行中使用了与上面相同的代码(有问题的提及)，并对它进行了微小的修改.正确的代码行如下.

So I've used the above same code (mentioned in question) with one tiny modification in this videoCapture.SetProperty line of code. the correct line of code is as below.

videoCapture.SetProperty(KnownCameraGeneralProperties.EncodeWithOrientation, -(videoCapture.SensorRotationInDegrees));

我只是在videoCapture.SensorRotationInDegrees前面加上一个减号(-)来反转它.

I just inverted the videoCapture.SensorRotationInDegrees by adding one minus sign (-) before it.

希望这对所有人有帮助.

Hope this helps all..

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