下面是个示例代码,你也可以将Canvas的brush style设置成bsClear,使得文本具有透明效果。
uses
Jpeg;
procedure TForm1.Button1Click(Sender: TObject);
var
Bmp : TBitmap;
Jpg : TJpegImage;
begin
try
Bmp := TBitmap.Create;
Jpg := TjpegImage.Create;
Jpg.LoadFromFile(‘c:img.jpg‘);
Bmp.Assign(Jpg);
Bmp.Canvas.Brush.Style := bsClear;
Bmp.Canvas.Font.Color := clYellow;
Bmp.Canvas.TextOut(10,10,‘Hello World‘);
Jpg.Assign(Bmp);
Jpg.SaveToFile(‘c:img2.jpg‘);
finally
bmp.Free;
jpg.Free;
end;
end;
uses
Jpeg;
procedure TForm1.Button1Click(Sender: TObject);
var
Bmp : TBitmap;
Jpg : TJpegImage;
begin
try
Bmp := TBitmap.Create;
Jpg := TjpegImage.Create;
Jpg.LoadFromFile(‘c:img.jpg‘);
Bmp.Assign(Jpg);
Bmp.Canvas.Brush.Style := bsClear;
Bmp.Canvas.Font.Color := clYellow;
Bmp.Canvas.TextOut(10,10,‘Hello World‘);
Jpg.Assign(Bmp);
Jpg.SaveToFile(‘c:img2.jpg‘);
finally
bmp.Free;
jpg.Free;
end;
end;