void __fastcall TForm1::Button1Click(TObject *Sender)
{
    Graphics::TBitmap *bmpImage = new Graphics::TBitmap;
    AnsiString asImagePathNFilename = edtImagePathNFilename->Text;
    int iImageWidth, iImageHeight;

    bmpImage->LoadFromFile(asImagePathNFilename);
    iImageWidth = bmpImage->Width;
    iImageHeight = bmpImage->Height;
    for (iWhichXPixel = 0; iWhichXPixel < iImageWidth; iWhichXPixel++)
    {
        for (iWhichYPixel = 0; iWhichYPixel < iImageHeight; iWhichYPixel++)
        {
            bmpImage->Canvas->Pixels[iWhichXPixel][iWhichYPixel] = 0xFFFFFF - bmpImage->Canvas->Pixels[iWhichXPixel][iWhichYPixel];
        }
    }
    delete bmpImage;
}

/*
This example shows how to draw directly to a Bitmap.  It
loads a bitmap from a file and then copies it to another
bitmap twice it's size.  Then the two bitmaps are
displayed on the form canvas.
*/

#include <memory>       //for STL auto_ptr class

void __fastcall TForm1::Button1Click(TObject *Sender)
{
  std::auto_ptr<Graphics::TBitmap> Bitmap(new Graphics::TBitmap);
  std::auto_ptr<Graphics::TBitmap> BigBitmap(new Graphics::TBitmap);
  TRGBTriple *ptr, *bigPtr;   // use a (byte *) for pf8bit color
  TPixelFormat pixForm, bigpixForm;
  try
  {
    Bitmap->LoadFromFile("../littlefac.bmp");
    pixForm = Bitmap->PixelFormat;
    bigpixForm  = BigBitmap->PixelFormat;
    Bitmap->PixelFormat = pf24bit;
    BigBitmap->PixelFormat = pf24bit;
    BigBitmap->Height = Bitmap->Height * 2;
    BigBitmap->Width = Bitmap->Width * 2;
    for (int y = 0; y < Bitmap->Height; y++)
    {
      ptr = reinterpret_cast<TRGBTriple *>(Bitmap->ScanLine[y]);
      for (int x = 0; x < Bitmap->Width; x++)
      {
        int bx = x * 2;
        int by = y * 2;
        bigPtr = reinterpret_cast<TRGBTriple *>(BigBitmap->ScanLine[by]);
        bigPtr[bx] = ptr[x];
        bigPtr[bx + 1] = ptr[x];
        bigPtr = reinterpret_cast<TRGBTriple *>(BigBitmap->ScanLine[by + 1]);
        bigPtr[bx] = ptr[x];
        bigPtr[bx + 1] = ptr[x];
      }
    }
    Canvas->Draw(0, 0, Bitmap.get());
    Canvas->Draw(200, 200, BigBitmap.get());
  }
  catch (...)
  {
    ShowMessage("Could not load or alter bitmap");
  }
}

    __property TColor Pixels[int X][int Y] = {read=GetPixel, write=SetPixel};