C# Bitmap BitmapImage bitmapsource

Question

I have some code I found somewhere on the Net.

unsafe static Bitmap SaveFrame(IntPtr pFrame, int width, int height)
    {
        try
        {
            int x, y;
            int linesize = width * 3;
            byte* scan0 = (byte*)Marshal.ReadIntPtr(pFrame);

            IntPtr bufferPtr = Marshal.AllocHGlobal(linesize * height);
            byte* buffer = (byte*)bufferPtr;

            for (y = 0; y < height; y++)
            {
                for (x = 0; x < linesize; x = x + 3)
                {
                    *buffer++ = (byte)*(scan0 + y * linesize + x + 2);
                    *buffer++ = (byte)*(scan0 + y * linesize + x + 1);
                    *buffer++ = (byte)*(scan0 + y * linesize + x);
                }
            }
            Bitmap b = new Bitmap(width, height, linesize, System.Drawing.Imaging.PixelFormat.Format24bppRgb, bufferPtr);



            return b;
        }
        catch (Exception ex) { throw new Exception(ex.Message); }
    }

This above code gives me a valid Bitmap, However I'm using WPF and want it to be in a BitmapImage

Without going through this process, Im trying the code

byte[] ptr = ....
Marshal.Copy(pFrame, ptr , 0, ptr .Length);
BitmapImage aBitmapImage = new BitmapImage(); 
aBitmapImage.BeginInit();
aBitmapImage.StreamSource = new MemoryStream(ptr); //FLastImageMemStream;//
aBitmapImage.EndInit();

which does not work...

I have also tried

System.Windows.Media.Imaging.BitmapSource.Create(width, height, 96, 96,
    System.Windows.Media.PixelFormats.Rgb24, null, bufferPtr,linesize * height,
    width * 3 ));

which also does not give me an image it seems (after assigning it to the Source property of Image)

Can anyone give me any hints? Thanks Allen

Its really not clear what you are trying to achieve here. would display a bitmap. Is that what you are wanting to do? — Michael Shaw, Nov 16 '10 at 23:13

score 1 · Accepted Answer · answered Mar 31 '11 at 18:17

Loading the data directly into the BitmapImage didn't work because it's expecting data in an image file format, like you'd see in a .bmp or .png file. You supplied raw pixel data instead.

Your second approach looks like it should work but has some unnecessary steps to it. The code you found is rewriting the pixel data from BGR24 to RGB24, but you should be able to just load it in directly as BGR24:

System.Windows.Media.Imaging.BitmapSource.Create(width, height, 96, 96,
    System.Windows.Media.PixelFormats.Bgr24, null, pFrame, linesize * height,
    width * 3 ));

Anyway, do you have any details on why it's not giving you an image? Did you get any exceptions when creating the bitmap? Did it give the wrong colors or wrong size? Are you sure all the source data is there? What do you see on the properties of the BitmapSource after you create it?

score 0 · Answer 2 · edited May 23 '17 at 12:04

0

Load a WPF BitmapImage from a System.Drawing.Bitmap

edited May 23 '17 at 12:04

Community

1
1

answered Nov 16 '10 at 23:12

Stu

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Sorry but for performance reasons, I am trying to bypass the section where I am creating a Bitmap in the first place, I just want to pass in a byte array to a WPF BitmapImage component... I have an array of bytes which I have received from an encrypted file which I feed into the code which I found on the web And this works... But this code(it is unsafe as well) is using a Bitmap component. I am trying to find a way to do do this for WPF – TheWommies Nov 16 '10 at 23:24
Have you tried Seeking to the beginning of the stream after you create it? – Stu Nov 17 '10 at 00:10

C# Bitmap BitmapImage bitmapsource

2 Answers2