BitMapFile *getBMPData(string filename)
{
   BitMapFile *bmp = new BitMapFile;
   unsigned int size, offset, headerSize;
  
   // Read input file name.
   ifstream infile(filename.c_str(), ios::binary);
 
   // Get the starting point of the image data.
   infile.seekg(10);
   infile.read((char *) &offset, 4); 
   
   // Get the header size of the bitmap.
   infile.read((char *) &headerSize,4);

   // Get width and height values in the bitmap header.
   infile.seekg(18);
   infile.read( (char *) &bmp->sizeX, 4);
   infile.read( (char *) &bmp->sizeY, 4);

   // Allocate buffer for the image.
   size = bmp->sizeX * bmp->sizeY * 32;
   bmp->data = new unsigned char[size];

   // Read bitmap data.
   infile.seekg(offset);
   infile.read((char *) bmp->data , size);

   // Reverse color from abgr to rgba.
   int temp;
   for (int i = 0; i < size; i += 4)
   { 
      temp = bmp->data[i];
	  bmp->data[i] = bmp->data[i+3];
	  bmp->data[i+3] = temp;

	  temp = bmp->data[i+1];
	  bmp->data[i+1] = bmp->data[i+2];
	  bmp->data[i+2] = temp;

   }

   return bmp;
}