delphi实现.bmp位图旋转90度。急求！！！

Question

delphi位图图像旋转

Answer 1

注意：你要设置Timage的Strech属性为True，AutoSize不要设置为True，否则转换的过程会非常慢。
旋转JPG图像，必须要把JPG转换成BMP图像，所以我自定义了一个函数jptpbmp()Function TForm1.jptobmp(jpg:Tjpegimage):Tbitmap;
begin
  result:=nil;
  if Assigned(jpg) then
  begin
    result:=Tbitmap.Create;
    jpg.DIBNeeded;
    result.Assign(jpg);
  end;
end;然后放置了4个按钮，左转，右转，水平和垂直，代码为//左转
procedure TForm1.Button1Click(Sender: TObject);
var
i,j:integer;
Myimage:Tbitmap;
begin
Myimage:=Tbitmap.Create;
Myimage.Assign(jptobmp(Tjpegimage(image1.Picture.Graphic)));
image1.Picture.Bitmap.Height:=Myimage.Width;
image1.Picture.Bitmap.Width:=Myimage.Height;
image1.Picture.CleanupInstance;
for i := 0 to Myimage.Height do
  for j := 0 to Myimage.Width do
    image1.Canvas.Pixels[i,(-j+Myimage.Width)]:=Myimage.Canvas.Pixels[j,i];
Myimage.Free
end;//右转
procedure TForm1.Button2Click(Sender: TObject);
var
i,j:integer;
Myimage:Tbitmap;
begin
Myimage:=Tbitmap.Create;
Myimage.Assign(jptobmp(Tjpegimage(image1.Picture.Graphic)));
image1.Picture.Bitmap.Height:=Myimage.Width;
image1.Picture.Bitmap.Width:=Myimage.Height;
image1.Picture.CleanupInstance;
for i := 0 to Myimage.Height do
  for j := 0 to Myimage.Width do
    image1.Canvas.Pixels[(-i+Myimage.Height),j]:=Myimage.Canvas.Pixels[j,i];
Myimage.Free
end;//水平
procedure TForm1.Button3Click(Sender: TObject);
var
i,j:integer;
Myimage:Tbitmap;
begin
Myimage:=Tbitmap.Create;
Myimage.Assign(jptobmp(Tjpegimage(image1.Picture.Graphic)));
image1.Picture.Bitmap.Height:=Myimage.Height;
image1.Picture.Bitmap.Width:=Myimage.Width;
image1.Picture.CleanupInstance;
for i := 0 to Myimage.Height do
  for j := 0 to Myimage.Width do
    image1.Canvas.Pixels[(-j+Myimage.Width),i]:=Myimage.Canvas.Pixels[j,i];
Myimage.Free
end;//垂直
procedure TForm1.Button4Click(Sender: TObject);
var
i,j:integer;
Myimage:Tbitmap;
begin
Myimage:=Tbitmap.Create;
Myimage.Assign(jptobmp(Tjpegimage(image1.Picture.Graphic)));
image1.Picture.Bitmap.Height:=Myimage.Height;
image1.Picture.Bitmap.Width:=Myimage.Width;
image1.Picture.CleanupInstance;
for i := 0 to Myimage.Height do
  for j := 0 to Myimage.Width do
    image1.Canvas.Pixels[j,(-i+Myimage.Height)]:=Myimage.Canvas.Pixels[j,i];
Myimage.Free
end;
图片显示虽然是适应尺寸的，但是不影响保存后和原图的品质

Answer 2

顺时针90度
procedure TSeleteImageFrm.Button4Click(Sender: TObject);
var i,j:integer;
    k,all:Longint;
    im:Tbitmap;
begin
  GaugeFrm.show;
  GaugeFrm.Caption:='处理数据......';
  GaugeFrm.Gauge1.Progress:=0;
  im:=Tbitmap.Create;
  im.Assign(jpbmp(Tjpegimage(image1.Picture.Graphic)));
//确定旋转后位图的大小
  image1.Picture.Bitmap.Height:=im.Width;
  image1.Picture.Bitmap.Width:=im.Height;
  image2.Picture.Bitmap.Height:=im.Width;
  image2.Picture.Bitmap.Width:=im.Height;
  image1.Picture.CleanupInstance;  //清除图象
  image2.Picture.CleanupInstance;  //清除图象
  K:=0;
  all:=Trunc(im.Height*im.Width);
  for i:=0 to im.Height do
    for j:=0 to im.Width do
    begin
      K:=K+1;
      GaugeFrm.Gauge1.Progress:=Trunc(100*K/all);
      image1.Canvas.Pixels[(-i+im.Height),j]:=im.Canvas.Pixels[j,i];
      image2.Canvas.Pixels[(-i+im.Height),j]:=im.Canvas.Pixels[j,i];
    end;
  im.Free;
  ChangeImageSize;
  GaugeFrm.close;
end;反时针90度
procedure TSeleteImageFrm.Button6Click(Sender: TObject);
var i,j:integer;
    k,all:Longint;
    im:Tbitmap;
begin
  GaugeFrm.show;
  GaugeFrm.Caption:='处理数据......';
  GaugeFrm.Gauge1.Progress:=0;
  im:=Tbitmap.Create;
  im.Assign(jpbmp(Tjpegimage(image1.Picture.Graphic)));
//确定旋转后位图的大小
  image1.Picture.Bitmap.Height:=im.Width;
  image1.Picture.Bitmap.Width:=im.Height;
  image2.Picture.Bitmap.Height:=im.Width;
  image2.Picture.Bitmap.Width:=im.Height;
  image1.Picture.CleanupInstance;  //清除图象
  image2.Picture.CleanupInstance;  //清除图象
  K:=0;
  all:=Trunc(im.Height*im.Width);
  for i:=0 to im.Height do
    for j:=0 to im.Width do
    begin
      K:=K+1;
      GaugeFrm.Gauge1.Progress:=Trunc(100*K/all);
      image1.Canvas.Pixels[i,(-j+im.Width)]:=im.Canvas.Pixels[j,i];
      image2.Canvas.Pixels[i,(-J+im.Width)]:=im.Canvas.Pixels[j,i];
    end;
  im.Free;
  ChangeImageSize;
  GaugeFrm.close;
end;

Answer 3

颠倒
procedure TSeleteImageFrm.Button7Click(Sender: TObject);
var i,j:integer;
    k,all:Longint;
    im:Tbitmap;
begin
  GaugeFrm.show;
  GaugeFrm.Caption:='处理数据......';
  GaugeFrm.Gauge1.Progress:=0;
  im:=Tbitmap.Create;
  im.Assign(jpbmp(Tjpegimage(image1.Picture.Graphic)));
//确定旋转后位图的大小
  image1.Picture.Bitmap.Height:=im.Height;
  image1.Picture.Bitmap.Width:=im.Width;
  image2.Picture.Bitmap.Height:=im.Height;
  image2.Picture.Bitmap.Width:=im.Width;
  image1.Picture.CleanupInstance;  //清除图象
  image2.Picture.CleanupInstance;  //清除图象
  K:=0;
  all:=Trunc(im.Height*im.Width);
  for i:=0 to im.Width do
    for j:=0 to im.Height do
    begin
      K:=K+1;
      GaugeFrm.Gauge1.Progress:=Trunc(100*K/all);
      image1.Canvas.Pixels[(im.Width-i),(im.Height-j)]:=im.Canvas.Pixels[i,j];
      image2.Canvas.Pixels[(im.Width-i),(im.Height-j)]:=im.Canvas.Pixels[i,j];
    end;
  im.Free;
  ChangeImageSize;
  GaugeFrm.close;
end;

Answer 4

翻转（水平）
procedure TSeleteImageFrm.Button13Click(Sender: TObject);
var i,j:integer;
    k,all:Longint;
    im:Tbitmap;
begin
  GaugeFrm.show;
  GaugeFrm.Caption:='处理数据......';
  GaugeFrm.Gauge1.Progress:=0;
  im:=Tbitmap.Create;
  im.Assign(jpbmp(Tjpegimage(image1.Picture.Graphic)));
//确定旋转后位图的大小
  image1.Picture.Bitmap.Height:=im.Height;
  image1.Picture.Bitmap.Width:=im.Width;
  image2.Picture.Bitmap.Height:=im.Height;
  image2.Picture.Bitmap.Width:=im.Width;
  image1.Picture.CleanupInstance;  //清除图象
  image2.Picture.CleanupInstance;  //清除图象
  K:=0;
  all:=Trunc(im.Height*im.Width);
  for i:=0 to im.Height do
    for j:=0 to im.Width do
    begin
      K:=K+1;
      GaugeFrm.Gauge1.Progress:=Trunc(100*K/all);
      image1.Canvas.Pixels[(-j+im.Width),(i)]:=im.Canvas.Pixels[j,i];
      image2.Canvas.Pixels[(-J+im.Width),(i)]:=im.Canvas.Pixels[j,i];
    end;
  im.Free;
  ChangeImageSize;
  GaugeFrm.close;
end;
有此代码是显示进度条的，可以删除。使用二个image，目的是显示选择框，你可以只用一个。

Answer 5

这都是用的坐标呀。这样的效率有点差呀试试BitMap.ScanLine 比那个速度快10倍不止。