Metro应用程序中像素字节进位的位图（Win 8）

Question

I want to create a bitmap from a byte array of pixel in metro Apps. Earlier below function was used for the same:

//Here create the Bitmap to the know height, width and format
  Bitmap bmp = new Bitmap( 352, 288, PixelFormat.Format24bppRgb);  

  //Create a BitmapData and Lock all pixels to be written 
  BitmapData bmpData = bmp.LockBits(
                       new Rectangle(0, 0, bmp.Width, bmp.Height),   
                       ImageLockMode.WriteOnly, bmp.PixelFormat);

  //Copy the data from the byte array into BitmapData.Scan0
  Marshal.Copy(data, 0, bmpData.Scan0, data.Length);


  //Unlock the pixels
  bmp.UnlockBits(bmpData);


  //Return the bitmap 
  return bmp;

but BitmapData class is not present in windows 8 now. Please suggest any alternate way for the same.

thanks, Pankaj

Answer 1

If I am not entirely mistaken, part of the code above is taken from the Evil DICOM library, from the ImageHelper.GetBitmap method.

I have myself made an attempt to port this code to Metro (or whatever Microsoft is going to call it eventually), and here is what the Metro analogue of ImageHelper.GetBitmap looks like in my port:

public static BitmapSource GetBitmap(float[] pixels, ImageProperties properties)
{
    var bmp = new WriteableBitmap(properties.Rows, properties.Columns);

    using (var stream = bmp.PixelBuffer.AsStream())
    {
        var bytes = new byte[4 * pixels.Length];
        for (int i = 0; i < pixels.Length; i++)
        {
            var greyness = properties.WindowAndLevel.GetValue(pixels[i]);
            bytes[4 * i] = greyness;
            bytes[4 * i + 1] = greyness;
            bytes[4 * i + 2] = greyness;
            bytes[4 * i + 3] = 0xff;
        }

        stream.Write(bytes, 0, bytes.Length);
    }

    return bmp;
}

(Actually, I am using stream.WriteAsync in my own code, requiring the method to be declared as async . However, this is irrelevant for the above question as such.)

This answer is similar to Diogo's, but if you are not already "there" hopefully this answer can lead you more directly to your goal.

UPDATE

I have now published my Evil Dicom port to Metro on Github. You can find the repository here , and here is also a display from a very simple Metro application where I have used this Evil Dicom Metro port:

Answer 2

Try using the WritableBitmap class.

Something like that should work:

WriteableBitmap newBmp = new WriteableBitmap(width, height);
Stream stream = newBmp.PixelBuffer.AsStream();

stream.Seek(0, 0);
stream.Write(bytes, 0, bytes.Length);
newBmp.Invalidate();

You'll probably have to use the following namespaces for that to work:

using System.Runtime.InteropServices.WindowsRuntime;
using Windows.Graphics.Imaging;
using Windows.Storage.Streams;