Работа со scanline

TPNGObject->Canvas->Pixels[40, 50]; // То же что и "TBitmap->Canvas->Pixels[40, 50]", медленно;
TPNGObject->Pixels[40, 50]; // А вот это должно работать как надо;

TPNGObject * pngImage = new TPNGObject;
...
pngImage->Assign(bmpImage); // (Image1->Picture->Graphic);
...
delete pngImage;

for( int y = 0; y < Image1->Picture->Bitmap->Height; y++ )
{
    Byte *ptr  = (Byte *)Image1->Picture->Bitmap->ScanLine[y];
 
    for( int x = 0, j = 0; x < Image1->Picture->Bitmap->Width; x++ )
    {
        int BlueColor  = ptr[j++];
        int GreenColor = ptr[j++];
        int RedColor   = ptr[j++];
    }
}

Byte *ptr  = (Byte *)Image1->Picture->Bitmap->ScanLine[1];
int BlueColor  = ptr[1];
int GreenColor = ptr[2];
int RedColor   = ptr[3];

Byte *ptr  = (Byte *)Image1->Picture->Bitmap->ScanLine[1];
int BlueColor  = ptr[4];
int GreenColor = ptr[5];
int RedColor   = ptr[6];

Graphics::TBitmap *Bitmap = new Graphics::TBitmap;
Bitmap->Assign(Image1->Picture->Graphic);

Byte *ptr  = (Byte *)Image1->Picture->Bitmap->ScanLine[0];
int BlueColor  = ptr[0];
int GreenColor = ptr[1];
int RedColor   = ptr[2];

Byte *ptr  = (Byte *)Image1->Picture->Bitmap->ScanLine[1];
int BlueColor  = ptr[3];
int GreenColor = ptr[4];
int RedColor   = ptr[5];

if( Image1->Picture->Bitmap->PixelFormat == pf24bit )
{
    //...
}