xaml - Windows 8 商店应用程序中的模糊效果？

Question

您如何为 Windows 8 应用商店应用程序的 XAML 中的 UI 元素（如 aStackPanel或 a ）添加模糊效果？Rectangle

我正在考虑类似BlurEffectWPF 中的内容，如此处所示。任何解决方案都应该适合动画或至少每秒更新多次。

Answer 1

您可以使用此库来模糊和写入图像。

它可能看起来像这样：

// Blit a bitmap using the additive blend mode at P1(10, 10)
writeableBmp.Blit(new Point(10, 10), bitmap, sourceRect, Colors.White, WriteableBitmapExtensions.BlendMode.Additive);

或者，您可以编写自己的（或使用其他人编写的代码），类似于：

private static Bitmap Blur(Bitmap image, Rectangle rectangle, Int32 blurSize)
{
    Bitmap blurred = new Bitmap(image.Width, image.Height);

    // make an exact copy of the bitmap provided
    using(Graphics graphics = Graphics.FromImage(blurred))
        graphics.DrawImage(image, new Rectangle(0, 0, image.Width, image.Height),
            new Rectangle(0, 0, image.Width, image.Height), GraphicsUnit.Pixel);

    // look at every pixel in the blur rectangle
    for (Int32 xx = rectangle.X; xx < rectangle.X + rectangle.Width; xx++)
    {
        for (Int32 yy = rectangle.Y; yy < rectangle.Y + rectangle.Height; yy++)
        {
            Int32 avgR = 0, avgG = 0, avgB = 0;
            Int32 blurPixelCount = 0;

            // average the color of the red, green and blue for each pixel in the
            // blur size while making sure you don't go outside the image bounds
            for (Int32 x = xx; (x < xx + blurSize && x < image.Width); x++)
            {
                for (Int32 y = yy; (y < yy + blurSize && y < image.Height); y++)
                {
                    Color pixel = blurred.GetPixel(x, y);

                    avgR += pixel.R;
                    avgG += pixel.G;
                    avgB += pixel.B;

                    blurPixelCount++;
                }
            }

            avgR = avgR / blurPixelCount;
            avgG = avgG / blurPixelCount;
            avgB = avgB / blurPixelCount;

            // now that we know the average for the blur size, set each pixel to that color
            for (Int32 x = xx; x < xx + blurSize && x < image.Width && x < rectangle.Width; x++)
                for (Int32 y = yy; y < yy + blurSize && y < image.Height && y < rectangle.Height; y++)
                    blurred.SetPixel(x, y, Color.FromArgb(avgR, avgG, avgB));
        }
    }

    return blurred;
}

要获取第二种方法的单个像素，请参见此处：

BitmapImage iSrc

var array = new int[iSrc.PixelWidth * iSrc.PixelHeight]

var rect = new Int32Rect(0, 0, iSrc.PixelWidth, iSrc.PixelHeight)

iSrc.CopyPixels(rect, array, iSrc.PixelWidth * 4, 0)