在UWP 将BitmapImage转换为 WriteableBitmap

您可以直接从文件将图像加载到WriteableBitmap对象。

var filePicker = new FileOpenPicker();
filePicker.FileTypeFilter.Add(".jpg");
var result = await filePicker.PickSingleFileAsync();

if (result != null)
{
    using (IRandomAccessStream stream = await result.OpenAsync(FileAccessMode.Read))
    {
        BitmapDecoder decoder = await BitmapDecoder.CreateAsync(stream);
        WriteableBitmap bmp = new WriteableBitmap((int)decoder.PixelWidth, (int)decoder.PixelHeight);
        bmp.SetSource(stream);

        // show the image in the UI if you want.
        MyImage.Source = bmp;
    }
}
这样你可以使用WriteableBitmap，你可以使用WriteableBitmapEx库。