Delphi常见图象格式转换技术

TJPEGScale = (jsFullSize, jsHalf, jsQuarter, jsEighth);//图片大小（全部，1/2，1/4，1/8）
TBitmap.pixelFormat:=pf8bit;//图片位数（8，24）

给大家提供几个常用的图象格式转换方法和其转换函数
希望可以对你有帮助
1. ICO图标转换BMP格式
2. 32x32 BMP格式图象转换为 ICO格式
3.转换BMP->JPEG文件格式
4.JPEG 转换为BMP函数
5.Bmp转换为JPEG文件格式函数
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1.Chinese : ICO图标转换BMP格式
English :(Conversion from ICO to BMP)
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var
Icon : TIcon;
Bitmap : TBitmap;
begin
Icon := TIcon.Create;
Bitmap := TBitmap.Create;
Icon.LoadFromFile('c:\picture.ico');
Bitmap.Width := Icon.Width;
Bitmap.Height := Icon.Height;
Bitmap.Canvas.Draw(0, 0, Icon );
Bitmap.SaveToFile('c:\picture.bmp');
Icon.Free;
Bitmap.Free;
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2.Chinese: 32x32 BMP格式图象转换为 ICO格式
English :32x32 bit Bitmaps to ICO's
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procedure TForm1.Button1Click(Sender: TObject);
var winDC, srcdc, destdc : HDC;
oldBitmap : HBitmap;
iinfo : TICONINFO;
begin
GetIconInfo(Image1.Picture.Icon.Handle, iinfo);

WinDC := getDC(handle);
srcDC := CreateCompatibleDC(WinDC);
destDC := CreateCompatibleDC(WinDC);
oldBitmap := SelectObject(destDC, iinfo.hbmColor);
oldBitmap := SelectObject(srcDC, iinfo.hbmMask);

BitBlt(destdc, 0, 0, Image1.picture.icon.width,
Image1.picture.icon.height,
srcdc, 0, 0, SRCPAINT);
Image2.picture.bitmap.handle := SelectObject(destDC, oldBitmap);
DeleteDC(destDC);
DeleteDC(srcDC);
DeleteDC(WinDC);

image2.Picture.Bitmap.savetofile(ExtractFilePath(Application.ExeName)
+ 'myfile.bmp');
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
image1.picture.icon.loadfromfile('c:\myicon.ico');
end;

end.
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3. Chinese:转换BMP->JPEG文件格式
Englsh:convert the bitmap into a JPEG file format
------------------------------------------------------------------
var
MyJpeg: TJpegImage;
Image1: TImage;
begin
Image1:= TImage.Create;
MyJpeg:= TJpegImage.Create;
Image1.LoadFromFile('TestImage.BMP'); // 读取Bitmap文件
MyJpeg.Assign(Image1.Picture.Bitmap);
object
MyJpeg.SaveToFile('MyJPEGImage.JPG'); //保存JPEG
end;

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4.JPEG 转换为BMP函数

procedure Jpg2Bmp(const source,dest:string);
var
MyJpeg: TJpegImage;
bmp: Tbitmap;
begin
bmp:=tbitmap.Create;
MyJpeg:= TJpegImage.Create;
try
myjpeg.LoadFromFile(source);
bmp.Assign(myjpeg);
bmp.SaveToFile(dest);
finally
bmp.free;
myjpeg.Free;
end;
end;

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5.Bmp转换为JPEG文件格式函数
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procedure Bmp2Jpg(const source,dest:string;const scale:byte);
var
MyJpeg: TJpegImage;
Image1: TImage;
begin
Image1:= TImage.Create(application);
MyJpeg:= TJpegImage.Create;
try
Image1.Picture.Bitmap.LoadFromFile(source);
MyJpeg.Assign(Image1.Picture.Bitmap);
MyJpeg.CompressionQuality:=scale;
MyJpeg.Compress;
MyJpeg.SaveToFile(dest);
finally
image1.free;
myjpeg.Free;
end;
end;
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http://www.cnblogs.com/FKdelphi/p/4654575.html