我有两个位图图像,我想将它们合并在一起。我发现我可以用 writeablebitmap 做到这一点,但我如何首先将这些图像转换为 writeablebitmaps?
更新:我找不到直接将位图转换为可写位图的方法,所以我所做的是将我的位图写入隔离存储并在流对象中再次读取它。之后,可以使用 Xyroid 下面给出的代码来合并图像并将合并后的图像转换为位图。
最佳答案
在这里,我为您提供了合并两张图片的代码。 WinRT 的 WriteableBitmap 则不同,它的构造函数将高度和宽度作为参数。我用过WriteableBitmapEx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。
更新 1
假设你已经有两个BitmapImage
img1
和img2
,那么这样做
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;
}
关于c# - 我可以将图像/位图转换为可写位图吗?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/15729164/