jpg图片处理，可缩放，点某个位置后出现一个矩形框，并将这个框里的图复制到屏幕另外的地方，如有源代码者单独给100分

Question

unit Jpeg 提供对JPEG的支持。你可以看DEMO 或者是 HELP目录你的具体例子。要操作的话。你转换成BMP处理。要放大。你简单的可以用 COPYRECT （） 和 STRETCHDRAW（）来实现。
要想放大后效果好些。可以在用BMP。SCANLINE[]方法做一些模糊什么的操作。相关问题论坛帖子不少。自己找吧。

Answer 1

我也自己试过，放大缩小已经解决，其他的图象部分处理的也尝试过，就是有错误。我也知道用copyrect和stretchdraq,我需要具体的说明，谢谢了

Answer 2

现在的关键是点某个位置的车牌后，在另外的image2中放大显示这个点的附近区域的图片，也就是车牌

Answer 3

8用另外给分了。。我闲着无聊。随便写了点。。能用。呵呵
unit asdf;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, Jpeg,ExtCtrls, StdCtrls, ExtDlgs;type
  TForm1 = class(TForm)
    ScrollBox1: TScrollBox;
    Image1: TImage;
    OP: TOpenPictureDialog;
    Button1: TButton;
    PaintBox1: TPaintBox;
    procedure Button1Click(Sender: TObject);
    procedure Image1MouseMove(Sender: TObject; Shift: TShiftState; X,
      Y: Integer);
  private
    { Private declarations }
    OldP,NewP:TPoint;
    procedure JpgToBmp(JpegImageFileName:String; DstBmp: TBitmap);
    procedure BmpToJpg(SrcBmp:TBitmap; DstJpgFileName:string);
    procedure ZoomInRect(SrcDC: TCanvas;SrcRect:TRect; DstDC: TCanvas;
  DstRect: TRect);
  public
    { Public declarations }  end;var
  Form1: TForm1;implementation{$R *.dfm}{ TForm1 }procedure TForm1.JpgToBmp(JpegImageFileName:string; DstBmp: TBitmap);
var
jpg:TJpegImage;
begin
  jpg:=TJpegImage.Create;
  try
    jpg.LoadFromFile(JpegImageFileName);
    DstBmp.Assign(Jpg);
  finally
  jpg.free;
  end;end;procedure TForm1.Button1Click(Sender: TObject);
begin
 if op.Execute then
 begin
  image1.Picture.LoadFromFile(op.filename);
  JpgToBmp(op.filename,Image1.Picture.Bitmap);
  OldP:=Point(10000,10000);
  NewP:=OldP;
 end;
end;procedure TForm1.BmpToJpg(SrcBmp:TBitmap; DstJpgFileName:string);
var
jpg:TJpegImage;
begin
  jpg:=TJpegImage.Create;
  try
   jpg.Assign(SrcBmp);
   jpg.SaveToFile(DstJpgFileName);
  finally
  jpg.free;
  end;end;procedure TForm1.ZoomInRect(SrcDC: TCanvas;SrcRect:TRect; DstDC: TCanvas;
  DstRect: TRect);
var
bmp:TBitmap;
begin
  bmp:=TBitmap.Create;
  try
   bmp.width:=SrcRect.right-SrcRect.left;
   bmp.height:=SrcRect.Bottom-SrcRect.top;
   with  bmp.Canvas do
   begin
   CopyRect(Rect(0,0,bmp.Width,Bmp.Height),SrcDC,SrcRect);
   end;
  DstDC.StretchDraw(DstRect,bmp);
  //DstDC.Draw(0,0,bmp);
  finally
  bmp.free;
  end;
end;procedure TForm1.Image1MouseMove(Sender: TObject; Shift: TShiftState; X,
  Y: Integer);
begin
if image1.Picture.Bitmap.Empty  then  exit;
 ZoomInRect(Image1.Canvas,Rect(X-20,Y-10,X+20,Y+10),PaintBox1.Canvas,
     Rect(0,0,120,60));
    with image1.Canvas do
    begin
     if OldP.x<>10000 then
       begin
     Brush.Style:=bsClear;
     Pen.Mode:=pmNot;
     Rectangle(OldP.x-22,OldP.y-12,OldP.x+22,OldP.Y+12);
       end;
       NewP:=Point(X,Y);
     Brush.Style:=bsClear;
     Pen.Mode:=pmNot;
     Rectangle(Newp.X-22,NewP.Y-12,NewP.X+22,NEwP.Y+12);
     OldP:=NewP;
   end;
end;end.