如何使用UWP的MediaElement来显示图片？

Question

在UWP应用程序中，MediaElement用于播放视频、音频和图片。 对于视频和音频播放来说，它效果很好。但对于图片来说，就有些问题了。 代码如下。当我选择一张图片时，例如png 文件，然后您可以看到 MediaElement 上显示的错误信息

video

。

错误：不支持的视频类型或无效的文件路径

 private async void loadButton_Click(object sender, RoutedEventArgs e)
   {
       //Create a new picker
       FileOpenPicker filePicker = new FileOpenPicker();

       //Add filetype filters.  In this case wmv and mp4.
       filePicker.FileTypeFilter.Add(".wmv");
       filePicker.FileTypeFilter.Add(".mp4");
       filePicker.FileTypeFilter.Add(".mp3");
       filePicker.FileTypeFilter.Add(".png");

       //Set picker start location to the video library
       filePicker.SuggestedStartLocation = PickerLocationId.VideosLibrary;

       //Retrieve file from picker
       StorageFile file = await filePicker.PickSingleFileAsync();

       //If we got a file, load it into the media element
       if (file != null)
       {
           IRandomAccessStream stream = await file.OpenAsync(FileAccessMode.Read);
           video.SetSource(stream, file.ContentType);
       }
   }

错误信息：

源码来自 https://learn.microsoft.com/en-us/samples/microsoft/windows-universal-samples/basicmediacasting/ 我的最终目标是通过DLNA将视频、音频和图片投射到远程智能电视，但这里被阻止了。

Answer 1

MediaElement

仅支持可流式传输的格式，因此视频和音频格式可以使用，但图像不行。

要使其工作，您必须将图像转换为视频。

private async void loadButton_Click(object sender, RoutedEventArgs e)
{
    //Create a new picker
    FileOpenPicker filePicker = new FileOpenPicker();
    
    //Add filetype filters.  In this case wmv and mp4.
    filePicker.FileTypeFilter.Add(".wmv");
    filePicker.FileTypeFilter.Add(".mp4");
    filePicker.FileTypeFilter.Add(".mp3");
    filePicker.FileTypeFilter.Add(".png");
    
    //Set picker start location to the video library
    filePicker.SuggestedStartLocation = PickerLocationId.VideosLibrary;
    
    //Retrieve file from picker
    StorageFile file = await filePicker.PickSingleFileAsync();
    
    if (file == null)
    {
        //Show error message
        return;
    }

    //If we got an image, convert it to video
    if (file.ContentType.StartsWith("image/"))
    {
        //TODO: Create video from the image and save it to temp location
        //TODO: Replace current file variable with newly created video file

        if(file == null)
        {
            //Show error message
            return;
        }
    }


    IRandomAccessStream stream = await file.OpenAsync(FileAccessMode.Read);
    video.SetSource(stream, file.ContentType);
}