首页 > OOP语言 > Delphi > 正文

再学GDI+[90]: TGPImage(10) - 获取图像的调色板信息
2012-05-27 00:00:00   来源:www.bianceng.cn   评论:0 点击:

暂时无描述信息

本例效果图:

\

代码文件:unit Unit1;
interface
uses
 Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
 Dialogs, StdCtrls, Grids;
type
 TForm1 = class(TForm)
  DrawGrid1: TDrawGrid;
  OpenDialog1: TOpenDialog;
  Button1: TButton;
  procedure FormCreate(Sender: TObject);
  procedure FormDestroy(Sender: TObject);
  procedure FormPaint(Sender: TObject);
  procedure Button1Click(Sender: TObject);
 end;
var
 Form1: TForm1;
implementation
{$R *.dfm}
uses GDIPOBJ, GDIPAPI, Math;
var
 img: TGPImage;
procedure TForm1.FormCreate(Sender: TObject);
begin
 {调整 DrawGrid1 显示效果}
 with DrawGrid1 do
 begin
  Align := alRight;
  Width := 180;
  FixedCols := 0;
  FixedRows := 0;
  DefaultColWidth := 10;
  DefaultRowHeight := 10;
  ColCount := 0;
  RowCount := 1;
  DefaultDrawing := False;
  ScrollBars := ssNone;
 end;
 Button1.Left := ClientWidth - DrawGrid1.Width - Button1.Width;
 Button1.Top := 0;
 img := TGPImage.Create;
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
 img.Free;
end;
procedure TForm1.FormPaint(Sender: TObject);
var
 g: TGPGraphics;
begin
 g := TGPGraphics.Create(Self.Canvas.Handle);
 g.DrawImage(img, 0, 0, img.GetWidth, img.GetHeight);
 g.Free;
end;
procedure TForm1.Button1Click(Sender: TObject);
var
 Palette: PColorPalette; {调色板指针}
 ColorNum: Integer;   {调色板中的颜色总数}
 Colors: PGPColor;    {调色板中的颜色数组指针}
 i: Integer;
begin
 OpenDialog1.Filter := 'All (*.png;*.gif;*.bmp;*.tif;*.jpg)|*.png;*.gif;*.bmp;*.tif;*.jpg';
 if not OpenDialog1.Execute then Exit;
 img.Free;
 img := TGPImage.Create(OpenDialog1.FileName);
 Text := ExtractFileName(OpenDialog1.FileName);
 {为调色板分配内存}
 GetMem(Palette, img.GetPaletteSize);
 {获取调色板数据}
 img.GetPalette(Palette, img.GetPaletteSize);
 DrawGrid1.ColCount := 0;
 DrawGrid1.RowCount := 1;
 if Palette^.Count = 0 then
 begin
  ShowMessage('此图片没有调色板');
  Exit;
 end;
 ColorNum := Palette^.Count;
 Colors := @Palette.Entries; {调色板中颜色数组的指针}
 if ColorNum < 16 then DrawGrid1.ColCount := ColorNum else
 begin
  DrawGrid1.ColCount := 16;
  DrawGrid1.RowCount := ColorNum div 16;
 end;
 DrawGrid1.Refresh; {不刷新不行}
 for i := 0 to ColorNum - 1 do
 begin
  DrawGrid1.Canvas.Brush.Color := ARGBToColorRef(Colors^);
  DrawGrid1.Canvas.FillRect(DrawGrid1.CellRect(i mod 16, i div 16));
  Inc(Colors);
 end;
 FreeMem(Palette);
end;
end.

相关热词搜索:

上一篇:再学GDI+[91]: TGPImage(11) - 转灰度图像
下一篇:再学GDI+[89]: TGPImage(9) - 图像缩放时的质量(算法)

分享到: 收藏