FILE *Original_image_fp;
char data;
Original_image   = Edit1->Text;
// Read Original Image In Canvas (*.Raw)
Original_image_fp = fopen(Original_image.c_str(), "rb");
for (int y= 0;y<256;y  )
  for (int x= 0;x<256;x  ){
    data = fgetc(Original_image_fp);
    OriginalImageCanvas->Canvas->Pixels[x][y]=PutPixelGray(data);
  }
fclose(Original_image_fp);    TColor __fastcall TForm1::PutPixelGray(char Pixel)
{
return  (Pixel&0x000000FF)|((Pixel<<8)&0x0000FF00)|((Pixel<<16&0x00FF0000);
}

procedure TForm1.Button1Click(Sender: TObject);
var
   Source:TFileStream;
   x,y,z:Integer;
   data:TColor;
   Buf:array[0..65535] of Byte;
begin
   Source := TFileStream.Create('D:\test\030118\LENA.raw',fmShareDenyWrite);
   Source.ReadBuffer(Buf,65536);         
   z := 0;                               
   for y:=0 to 255 do begin
    for x:=0 to 255 do begin
      data := putpixelgray(Buf[z]);
      Image1.Canvas.Pixels[x,y] := RGB(data,data,data);
      Inc(z);
    end;
   end;
   Label1.Caption := 'LENA Origenal Image for 256x256  8 bits';
   Source.Free;
end;    function TForm1.PutPixelGray(Pixel:Byte):TColor;
begin
result:=(Pixel and $000000FF) or ( (Pixel shl 8) and $0000FF00) or ((Pixel shl 16) and $00FF0000);
end;

 
 TMemoryStream* ima = new TMemoryStream();
   ima->LoadFromFile(檔案名稱);
   BYTE bBuf=0;
   for (int i=0;iSize;i  )
    {
     ima->Position=i;
     bBuf=i;
     ima->Read(&bBuf,1);
     pixel[i]=bBuf;
    }
   delete ima;
   }
  for (y=0;y<512;y  )
   {
    for (x=0;x<512;x  )
     {
      color=((256*pixel[count] pixel[count 1]))/16;
      SetPixel(Image1->Canvas->Handle, x,y,TColor(RGB(color,color,color)));
      count =2;
     }
   }

引言:

 
FILE *Original_image_fp;
char data;
Original_image   = Edit1->Text;
// Read Original Image In Canvas (*.Raw)
Original_image_fp = fopen(Original_image.c_str(), "rb");
for (int y= 0;y<256;y  )
  for (int x= 0;x<256;x  ){
    data = fgetc(Original_image_fp);
    OriginalImageCanvas->Canvas->Pixels[x][y]=PutPixelGray(data);
  }
fclose(Original_image_fp);    TColor __fastcall TForm1::PutPixelGray(char Pixel)
{
return  (Pixel&0x000000FF)|((Pixel<<8)&0x0000FF00)|((Pixel<<16&0x00FF0000);
}

procedure TForm1.Button1Click(Sender: TObject);
var
   Source:TFileStream;
   x,y,z:Integer;
   data:TColor;
   Buf:array[0..65535] of Byte;
begin
   Source := TFileStream.Create('D:\test\030118\LENA.raw',fmShareDenyWrite);
   Source.ReadBuffer(Buf,65536);         
   z := 0;                               
   for y:=0 to 255 do begin
    for x:=0 to 255 do begin
      data := putpixelgray(Buf[z]);
      Image1.Canvas.Pixels[x,y] := RGB(data,data,data);
      Inc(z);
    end;
   end;
   Label1.Caption := 'LENA Origenal Image for 256x256  8 bits';
   Source.Free;
end;    function TForm1.PutPixelGray(Pixel:Byte):TColor;
begin
result:=(Pixel and $000000FF) or ( (Pixel shl 8) and $0000FF00) or ((Pixel shl 16) and $00FF0000);
end;

各位前輩，上述的兩段程式皆是用來讀取並秀出灰階 256x256 的程式。但不知為何以Delphi的方式所撰寫的執行起來比C的方式還慢？尤其在讀取的影像若為 512x512 或更大時其速度上的差異更是明顯，在效能較差的電腦上執行時其差異也相當明顯，不知是Delphi的限制還是使用了不適當的Function所致，請各位前輩多多指導該如何改善與修改，不甚感激，謝謝。

procedure TForm1.Button1Click(Sender: TObject);
var
   Source:TFileStream;
   x,y,z:Integer;
   data:byte;
   Buf:array[0..65535] of Byte;
begin
   Source := TFileStream.Create('D:\test\030118\LENA.raw',fmShareDenyWrite);
   Source.ReadBuffer(Buf,65536);         
   z := 0;                               
   for y:=0 to 255 do begin
    for x:=0 to 255 do begin
      data := Buf[z];
      Image1.Canvas.Pixels[x,y] := RGB(data,data,data);
      Inc(z);
    end;
   end;
   Label1.Caption := 'LENA Origenal Image for 256x256  8 bits';
   Source.Free;
end;     

引言: aquarius, 其實您說的那部份影響並不是很大，以第一段C的程式來讀512x512比第二段以Delphi程式來跑，其中的差異就相當明確了。

要快是吧!! 試試這段程式, 在我的電腦上, 512*512 只要 0.02 秒... :)

procedure TForm1.Button1Click(Sender: TObject);
const
  _iSize=512*512 ;
var
  bmp : TBitmap ;
  dwLast :DWORD ;
  Info: PBitmapInfo;
  InfoSize: Cardinal;
  Image, OrgImage: PByte;
  ImageSize: Cardinal;
  i : integer ;
  b : byte ;
  pb : pbyte ;
  ms : TMemoryStream ;
begin
  ms:=TMemoryStream.Create ;
  if FileExists('test.raw') then
    ms.LoadFromFile('test.raw')
  else
    begin
    for i:=0 to _iSize-1 do
      begin
      b:=i mod 256 ;
      ms.Write(b,1) ;
      end ;
    ms.SaveToFile('test.raw') ;
    end ;      dwLast:=GetTickCount ;
  bmp:=TBitmap.Create ;
  bmp.PixelFormat:=pf24bit ;
  bmp.Width:=512 ;
  bmp.Height:=512 ;      pb:=ms.Memory ;
  with bmp do
    begin
    GetDIBSizes(Handle, InfoSize, ImageSize);
    Info := AllocMem(InfoSize);
    try
      Image := AllocMem(ImageSize);
      OrgImage:=Image ;
      try
        GetDIB(Handle, Palette, Info^, Image^);
        for i:=0 to _iSize-1 do
          begin
          pbyte(Image)^:=pb^ ;
          inc(Image) ;
          pbyte(Image)^:=pb^ ;
          inc(Image) ;
          pbyte(Image)^:=pb^ ;
          inc(Image) ;              inc(pb) ;
          end ;
        Image:=OrgImage ;
        
        /// SetDIBits(canvas.handle,Handle,0,512,Image,info^,DIB_RGB_COLORS);
        with Info^.bmiHeader do
          StretchDIBits(canvas.Handle,
                        0,
                        0,
                        511,
                        511,
                        0,
                        0,
                        biWidth,
                        biHeight,
                        Image,
                        Info^,
                        DIB_RGB_COLORS,
                        SRCCOPY);
      finally
        FreeMem(Image, ImageSize);
        end;
    finally
      FreeMem(Info, InfoSize);
      end;
    end;      image1.picture.graphic:=bmp ;
  bmp.free ;
  caption:=format('time=%d',[getTickCount-dwLast]) ;
end;     

這樣夠快了吧!!... ...

引言: aquarius 謝謝您的幫忙，的確相當相當快了。但相較於C的寫法，C著實簡單多了，為什麼會相差這麼多？

一樣的寫法為什麼不同的 COMPILER 編出來速度會差這麼多, 這個問題要去問做 COMPILER 的人呀!!... :) DELPHI 的 PIXELS FUNCTION 指令很慢, 因為他是被層層的物件包起來的. 因為已經很明確的知道要做什麼動作, 所以我改用 Memory 的運算. 用這種方式來做, 大概只有用組合語言來做才會更快了.... ...