使用WPF將位圖複製到其他位圖

Question

我需要使用WPF將位圖放入另一個位圖的中心。

我設法用我想要的尺寸創建一張空白圖片，但我不明白如何將其他BitmapFrame複製到它。

BitmapSource bs = BitmapSource.Create(
    width, height, 
    dpi, dpi, 
    PixelFormats.Rgb24, 
    null, 
    bits, 
    stride); 

Answer 1

此鏈接可能會有所幫助： http://msdn.microsoft.com/en-au/library/ms172505(v=VS.90).aspx 特別是「要複製一個位圖的一部分」部分

Answer 2

您應該使用WriteableBitmap的，寫像素緩衝區。使用BitmapSource.CopyPixels從BitmapSource複製到數組，然後使用WriteableBitmap.WritePixels將數組複製到WriteableBitmap。

這裏是一個註釋實現

XAML

<Image Name="sourceImage" Height="50" 
     Source="/WpfApplication1;component/Images/Gravitar.bmp" /> 
<Image Name="targetImage" Height="50"/> 

代碼

// Quick and dirty, get the BitmapSource from an existing <Image> element 
// in the XAML 
BitmapSource source = sourceImage.Source as BitmapSource; 

// Calculate stride of source 
int stride = source.PixelWidth * (source.Format.BitsPerPixel/8); 

// Create data array to hold source pixel data 
byte[] data = new byte[stride * source.PixelHeight]; 

// Copy source image pixels to the data array 
source.CopyPixels(data, stride, 0); 

// Create WriteableBitmap to copy the pixel data to.  
WriteableBitmap target = new WriteableBitmap(
    source.PixelWidth, 
    source.PixelHeight, 
    source.DpiX, source.DpiY, 
    source.Format, null); 

// Write the pixel data to the WriteableBitmap. 
target.WritePixels(
    new Int32Rect(0, 0, source.PixelWidth, source.PixelHeight), 
    data, stride, 0); 

// Set the WriteableBitmap as the source for the <Image> element 
// in XAML so you can see the result of the copy 
targetImage.Source = target;