private async void MainPage_Loaded2(object sender, RoutedEventArgs e)
{
GaussianBlurFilter filter = new GaussianBlurFilter();
WriteableBitmap wb = new WriteableBitmap(600, 500);
StorageFile file = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///a.jpg"));
using (IRandomAccessStream fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read)) {
try {
await wb.SetSourceAsync(fileStream);
img.Source = wb;
MyImage mi = new MyImage(wb);// filter.process(new MyImage(wb));
int[] array = mi.colorArray;
byte[] result = new byte[array.Length * 4];
int j = 0;
for (int i = 0; i < array.Length; i++)
{
// b g r a vs argb
result[j++] = (byte)(array[i]); // b
result[j++] = (byte)(array[i] >> 8); // g
result[j++] = (byte)(array[i] >> 16); // r
result[j++] = (byte)(array[i] >> 24); // a
}
//using (MemoryStream ms = new MemoryStream(result))
//{
// BitmapImage src = new BitmapImage();
// src.SetSource(ms.AsRandomAccessStream());
// img.Source = src;
//}
// 将像素数据写入 WriteableBitmap 对象的像素缓冲区
using (Stream stream = wb.PixelBuffer.AsStream()) {
await stream.WriteAsync(result, 0, result.Length);
}
// 用像素缓冲区的数据绘制图片
wb.Invalidate();
//img.Source = mi.image;
} catch (Exception ex) {
Debug.WriteLine(ex.Message);
// The async action to set the WriteableBitmap's source may be canceled if the source is changed again while the action is in progress
}
}
//wb.SetSource()
}
/// <summary>
///
/// </summary>
/// <param name="level">[0,40]</param>
async void ApplyFilter(float level)
{
#region old
/*
* using (IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read))
* {
* BitmapDecoder decoder = await BitmapDecoder.CreateAsync(fileStream);
* // Scale image to appropriate size
* BitmapTransform transform = new BitmapTransform()
* {
* ScaledWidth = Convert.ToUInt32(wb.PixelWidth),
* ScaledHeight = Convert.ToUInt32(wb.PixelHeight)
* };
* PixelDataProvider pixelData = await decoder.GetPixelDataAsync(
* BitmapPixelFormat.Bgra8, // WriteableBitmap uses BGRA format
* BitmapAlphaMode.Straight,
* transform,
* ExifOrientationMode.IgnoreExifOrientation, // This sample ignores Exif orientation
* ColorManagementMode.DoNotColorManage
* );
*
*
*
* // An array containing the decoded image data, which could be modified before being displayed
* byte[] sourcePixels = pixelData.DetachPixelData();
* using (Stream stream = wb.PixelBuffer.AsStream())
* {
* await stream.WriteAsync(sourcePixels, 0, sourcePixels.Length);
* }
* }
*/
#endregion
// 拷贝
WriteableBitmap new_bitmap = await Utility.BitmapClone(wb);
// 添加高斯滤镜效果
MyImage mi = new MyImage(new_bitmap);
GaussianBlurFilter filter = new GaussianBlurFilter();
filter.Sigma = level;
filter.process(mi);
// 图片添加完滤镜的 int[] 数组
int[] array = mi.colorArray;
// byte[] 数组的长度是 int[] 数组的 4倍
byte[] result = new byte[array.Length * 4];
// 通过自加，来遍历 byte[] 数组中的值
int j = 0;
for (int i = 0; i < array.Length; i++)
{
// 同时把 int 值中 a、r、g、b 的排列方式，转换为 byte数组中 b、g、r、a 的存储方式
result[j++] = (byte)(array[i]); // Blue
result[j++] = (byte)(array[i] >> 8); // Green
result[j++] = (byte)(array[i] >> 16); // Red
result[j++] = (byte)(array[i] >> 24); // Alpha
}
// Open a stream to copy the image contents to the WriteableBitmap's pixel buffer
using (Stream stream = new_bitmap.PixelBuffer.AsStream()) {
await stream.WriteAsync(result, 0, result.Length);
}
img.Source = new_bitmap;// 把 WriteableBitmap 对象赋值给 Image 控件
// 用像素缓冲区的数据绘制图片
//new_bitmap.Invalidate();
}
