程式 . 生活 . D小調

<UserControl x:Class="WritableBitmapBnW.MainPage"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:d="http://schemas.microsoft.com/expression/blend/2008"

xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

mc:Ignorable="d"

d:DesignHeight="200" d:DesignWidth="500">

<Grid x:Name="LayoutRoot" Background="White">

<Image Height="65" HorizontalAlignment="Left" Margin="69,76,0,0" Name="imgSource" Stretch="Fill" VerticalAlignment="Top" Width="137" Source="bzspark.png" />

<Button Content="轉黑白圖" Height="28" HorizontalAlignment="Left" Margin="217,113,0,0" Name="btnConvertBnW" VerticalAlignment="Top" Width="76" FontSize="14" FontFamily="微軟正黑體" Click="btnConvertBnW_Click" />

<Image Height="65" HorizontalAlignment="Left" Margin="307,76,0,0" Name="imgTarget" Stretch="Fill" VerticalAlignment="Top" Width="137" />

</Grid>

</UserControl>

private void btnConvertBnW_Click(object sender, RoutedEventArgs e)

{

//讀入欲轉換的圖片並轉成為WritableBitmap

WriteableBitmap bitmap = new WriteableBitmap(this.imgSource, null);

for (int y = 0; y < bitmap.PixelHeight; y++)

{

for (int x = 0; x < bitmap.PixelWidth; x++)

{

//取得每一個pixel

int pixelLocation = bitmap.PixelWidth * y + x;

int pixel = bitmap.Pixels[pixelLocation];

byte[] pixBytes = BitConverter.GetBytes(pixel);

//每一個都除3

byte bnwPixel = (byte)(.333 * pixBytes[2]

+ .333 * pixBytes[1]

+ .333 * pixBytes[0]);

pixBytes[0] = bnwPixel;//b

pixBytes[1] = bnwPixel;//g

pixBytes[2] = bnwPixel;//r

//位置3是alpha 

//排列真是詭異阿..>< 剛好反過來s

//將處理後的pixel置回

bitmap.Pixels[pixelLocation] = BitConverter.ToInt32(pixBytes, 0);

}

}

//顯示結果

this.imgTarget.Source = bitmap;

}