这里我给你合并两个图像的代码。 WinRT的WriteableBitmap则不同,它的构造函数以高度和宽度作为参数。我用过可写位图Ex http://writeablebitmapex.codeplex.com/对于某些功能。
XAML
<Grid Background="{StaticResource ApplicationPageBackgroundThemeBrush}">
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<Canvas x:Name="BaseCanvas" Width="683" Height="768">
<Image Source="Assets/img1.png" />
<Image Source="Assets/img2.png" Canvas.Top="308" />
</Canvas>
<Image x:Name="imgTarget" Grid.Column="1" Stretch="None"/>
</Grid>
C#
protected async override void OnNavigatedTo(NavigationEventArgs e)
{
StorageFile destiFile = await ApplicationData.Current.TemporaryFolder.CreateFileAsync("Merged.png", CreationCollisionOption.ReplaceExisting);
WriteableBitmap wb;
wb = await Render();
using (IRandomAccessStream stream = await destiFile.OpenAsync(FileAccessMode.ReadWrite))
{
BitmapEncoder encoder = await BitmapEncoder.CreateAsync(
BitmapEncoder.PngEncoderId, stream);
Stream pixelStream = wb.PixelBuffer.AsStream();
byte[] pixels = new byte[pixelStream.Length];
await pixelStream.ReadAsync(pixels, 0, pixels.Length);
encoder.SetPixelData(BitmapPixelFormat.Bgra8, BitmapAlphaMode.Ignore,
(uint)wb.PixelWidth, (uint)wb.PixelHeight, 96.0, 96.0, pixels);
await encoder.FlushAsync();
}
var bitmp = new BitmapImage();
using (var strm = await destiFile.OpenReadAsync())
{
bitmp.SetSource(strm);
imgTarget.Source = bitmp;
}
}
private async Task<WriteableBitmap> Render()
{
var Assets = await Windows.ApplicationModel.Package.Current.InstalledLocation.GetFolderAsync("Assets");
StorageFile file1 = await Assets.GetFileAsync("img1.png");
StorageFile file2 = await Assets.GetFileAsync("img2.png");
BitmapImage i1 = new BitmapImage();
BitmapImage i2 = new BitmapImage();
using (IRandomAccessStream strm = await file1.OpenReadAsync())
{
i1.SetSource(strm);
}
using (IRandomAccessStream strm = await file2.OpenReadAsync())
{
i2.SetSource(strm);
}
WriteableBitmap img1 = new WriteableBitmap(i1.PixelWidth, i1.PixelHeight);
WriteableBitmap img2 = new WriteableBitmap(i2.PixelWidth, i2.PixelHeight);
using (IRandomAccessStream strm = await file1.OpenReadAsync())
{
img1.SetSource(strm);
}
using (IRandomAccessStream strm = await file2.OpenReadAsync())
{
img2.SetSource(strm);
}
WriteableBitmap destination = new WriteableBitmap((int)(img1.PixelWidth > img2.PixelWidth ? img1.PixelWidth : img2.PixelWidth), (int)(img1.PixelHeight + img1.PixelHeight));
destination.Clear(Colors.White);
destination.Blit(new Rect(0, 0, (int)img1.PixelWidth, (int)img1.PixelHeight),img1,new Rect(0, 0, (int)img1.PixelWidth, (int)img1.PixelHeight));
destination.Blit(new Rect(0, (int)img1.PixelHeight, (int)img2.PixelWidth, (int)img2.PixelHeight), img2, new Rect(0, 0, (int)img2.PixelWidth, (int)img2.PixelHeight));
return destination;
}
请注意,您必须添加System.Runtime.InteropServices.WindowsRuntime
命名空间。
UPDATE 1
假设如果你已经有两个BitmapImage
img1
and img2
,然后这样做
protected async override void OnNavigatedTo(NavigationEventArgs e)
{
StorageFile destiFile = await ApplicationData.Current.TemporaryFolder.CreateFileAsync("Merged.png", CreationCollisionOption.ReplaceExisting);
WriteableBitmap wb;
wb = await Render();
using (IRandomAccessStream stream = await destiFile.OpenAsync(FileAccessMode.ReadWrite))
{
BitmapEncoder encoder = await BitmapEncoder.CreateAsync(
BitmapEncoder.PngEncoderId, stream);
Stream pixelStream = wb.PixelBuffer.AsStream();
byte[] pixels = new byte[pixelStream.Length];
await pixelStream.ReadAsync(pixels, 0, pixels.Length);
encoder.SetPixelData(BitmapPixelFormat.Bgra8, BitmapAlphaMode.Ignore,
(uint)wb.PixelWidth, (uint)wb.PixelHeight, 96.0, 96.0, pixels);
await encoder.FlushAsync();
}
var bitmp = new BitmapImage();
using (var strm = await destiFile.OpenReadAsync())
{
bitmp.SetSource(strm);
imgTarget.Source = bitmp;
}
}
private async Task<WriteableBitmap> Render()
{
WriteableBitmap destination = new WriteableBitmap((int)(img1.PixelWidth > img2.PixelWidth ? img1.PixelWidth : img2.PixelWidth), (int)(img1.PixelHeight + img1.PixelHeight));
destination.Clear(Colors.White);
destination.Blit(new Rect(0, 0, (int)img1.PixelWidth, (int)img1.PixelHeight),img1,new Rect(0, 0, (int)img1.PixelWidth, (int)img1.PixelHeight));
destination.Blit(new Rect(0, (int)img1.PixelHeight, (int)img2.PixelWidth, (int)img2.PixelHeight), img2, new Rect(0, 0, (int)img2.PixelWidth, (int)img2.PixelHeight));
return destination;
}