Hi, I have two forms that both open windows, I need to get the response from a checkbox on Form2 and use it with Form1, Form2 is not a dialogue and needs to open all the time. Any ideas? Thanks.

Hi, I am trying to convert some of my BlitzBasic code over to C# and I cant get the following statment to work? Blitz: If paletteRmap[i]=0 And paletteGmap[i]=0 And paletteBmap[i]=0 C#: If (paletteRmap[best]=0 & paletteGmap[best]=0 & paletteBmap[best]=0) Error Message The left-hand side of an assignment must be a variable, property or indexer? Thanks.

Hi, I found a very quick method in the end using RtlMoveMemory:

[DllImport("kernel32")]
public static extern void RtlMoveMemory(IntPtr dest, IntPtr src, int len);

System.IntPtr pBuffer2 = Marshal.AllocHGlobal(BufferSize); //Assign unmanaged memory
RtlMoveMemory(pBuffer2, pBuffer, BufferSize); //Copy memory
byte* p2 = (byte*)(void*)pBuffer2;
// Use p2 to access image pixels
Marshal.FreeHGlobal(pBuffer2); //Free unmanaged memory

Thanks, for the help and hope this helps some one else.

Thanks, I tried to use Marshal.Copy but I could not get it to work, could you please show how to implement it? Cheers,

Thanks, I got it to work, but there must be an faster/easyer way to copy a block of memory? This is what I did to get it to work with Marshal.ReadByte, it gives me p2 which I can use on the copied image:

byte[] bytes = new byte[BufferSize];
for (int i = 0; i < BufferSize; i++)
bytes[i] = Marshal.ReadByte(pBuffer, i);

fixed (byte* pTmp = bytes)
{
System.IntPtr pBuffer2 = new IntPtr((void*)pTmp);
byte* p2 = (byte*)(void*)pBuffer2;
}

Thanks for the reply, I am very new to C# and I am just working off the Videocog tutorials, do you have an example of how Marshal.Copy works?

Hi, I am trying to use the third party VideoCog componet with C# and I need to copy a image frame? Videocog drops the frame into an rgb array in memory and I can then fast process the pixels using pointers. How can I create another copy of the frame from memory so that I can also access that via another pointer? Thanks...

1. private void videoCogControl1_FrameReady(double SampleTime, IntPtr pBuffer,

2.                                      int BufferSize, int Width, int Height)
   

3.  {
   

4.       unsafe
   

5.       {
   

6.            byte\* p = (byte\*)(void\*)pBuffer;
   

7.            int nWidth = Width \* 3;
   

8.            for (int y = 0; y < Height; y++)
   

9.            {
   

10.                 for (int x = 0; x < nWidth; x++)
    

11.                 {
    

12.                     p\[0\] = (byte)(255 - p\[0\]);
    

13.                     p++;
    

14.                 }
    

15.            }
    

16.        }   
    

17.  }
    

Hi, I have an image in memory as an RGB array, I need to make a fast copy of it? I access the image in usafe mode using the following pointer byte* p = (byte*)(void*)pBuffer; I need another copy of the data so that I can create a new pointer to it and leave my origional data unaffected. Thanks...

Hi, the problem is I have only used Blitz Basic before and I could jump to a pixel, eg GetColor(129,280)"Width,Height", with pointers I have to scan along the image for the data, I dont know how to jump to the pixel data I want?

Hi, I am very new to C# but I am modifying an image buffer directly within memory, I am scanning along moving the pointer to get the RGB of each pixel, but I need away to jump around the image memory and read the pixels at random rather than just p++ or p--? Thanks...

  unsafe 
            { 
                byte\* p = (byte\*)(void\*)pBuffer;
                for(int y = 0; y < Height; y++)
                {
                    for(int x = 0; x < Width; x++)
                    {
                        //B
                        int srcB = p\[0\];
                        p++;
                        //G
                        int srcG = p\[0\];
                        p++;
                        //R
                        int srcR = p\[0\];
                        p++;
                    }
                }
            }

Hi, I am new to C# and im working trying some image processing, im using this bit of code to invert the pixels on an image grabbed from a video file, how do I extract the RGB values from a pixel in C# using the image buffer? Speed is of the essence... Thanks in advance.

unsafe
{
byte* p = (byte *)(void *)pBuffer;
int nWidth = Width * 3;
for(int y = 0; y < Height; y++)
{
for(int x = 0; x < nWidth; x++ )
{
p[0] = (byte)(255-p[0]);
p++;