Question

我有Windows.Graphics.Imaging ImageStream。很容易将它作为XAML图像的来源：

BitmapImage bitmapImage = new BitmapImage();
bitmapImage.SetSource(imageStream);

XAMLImage.Source = bitmapImage;

但我没想出如何将它保存到Windows 10应用程序中的图像文件（png，jpg，...）。

Thnx寻求帮助。

Answer 1

你不能将BitmapImage保存为png或jepg文件，你应该使用WriteableBitmap代替。

CODE（如何将WriteableBitmap保存为JPEG）：

    var image = new WriteableBitmap(50, 50);

    var file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets/StoreLogo.png"));

    var content = await file.OpenReadAsync();

    image.SetSource(content);

    var saveAsTarget = await KnownFolders.PicturesLibrary.CreateFileAsync("saveas.jpg");

    BitmapEncoder encoder = await BitmapEncoder.CreateAsync(
        BitmapEncoder.JpegEncoderId, 
        await saveAsTarget.OpenAsync(FileAccessMode.ReadWrite));

    Stream pixelStream = image.PixelBuffer.AsStream();

    byte[] pixels = new byte[pixelStream.Length];

    await pixelStream.ReadAsync(pixels, 0, pixels.Length);

    encoder.SetPixelData(BitmapPixelFormat.Bgra8, BitmapAlphaMode.Ignore, (uint)image.PixelWidth, (uint)image.PixelHeight, 96.0, 96.0, pixels);

    await encoder.FlushAsync();

BitmapImage或ImageStream到图像文件 - Windows 10

1 个答案: