   pitch of image
  how to know a pitch of a source image? it need at HRESULT D3DXLoadSurfaceFromMemory(  LPDIRECT3DSURFACE9 pDestSurface,  CONST PALETTEENTRY * pDestPalette,  CONST RECT * pDestRect,  LPCVOID pSrcMemory,  D3DFORMAT SrcFormat,  UINT SrcPitch,  // here  CONST PALETTEENTRY * pSrcPalette,  CONST RECT * pSrcRect,  DWORD Filter,  D3DCOLOR ColorKey);Is it equal to image width in byte?   