[cocute]

puedes poner un Timage de fondo como mosaico con esta funcion

function TileImage(const FileName: TFileName; Sender: TObject): Boolean;
var
x, y: Integer;
Bmp: TBitmap;
begin
if FileExists(FileName) then
begin
bmp := TBitmap.Create;
try
bmp.LoadFromFile(FileName);
with (Sender as TImage) do
begin
for x := 0 to (Width div bmp.Width) do
for y := 0 to (Height div bmp.Height) do
Canvas.Draw(x * bmp.Width, y * bmp.Height, bmp);
end;
finally
bmp.Free;
end;
Result := True;
end
else
Result := False;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
if Opendialog1.Execute then
TileImage(OpenDialog1.FileName, Image1);
end;