我的程式是要讀進raw檔 直接顯示在image元件上 我的方法從讀檔到顯示出來要1秒多 感覺滿慢的 請問有沒有較快的方法可以做到此要求的？     

 
void __fastcall TForm1::Button1Click(TObject *Sender)
{
        width=217;
        high=390;
        w=h=h_top=0;
        if (OpenDialog1->Execute())
        {
                TMemoryStream* bin=new TMemoryStream();
                       bin->LoadFromFile(OpenDialog1->FileName);
                int dwSize=bin->Size;
                pixel=new BYTE[dwSize];
                bin->Read(pixel, dwSize);
                for (int y=0,count=0; y < high ; y  )
                 {
                          for (int x=0 ; x < width ; x  )
                          {
                                Image1->Canvas->Pixels[x][y]=RGB  (pixel[count],pixel[count],pixel[count]);
                                count=count 1;
                          }
                 }
                 delete bin;
        }
}    

發表人 - adamjr 於 2004/09/21 12:02:07

用ScanLine的方式作修改，應該可以加快處理速度， 將您的程式略作修改如下：< class="code"> void __fastcall TForm1::Button1Click(TObject *Sender) { int width=217; int height=390; Byte *ptr; if(OpenDialog1->Execute()) { TMemoryStream* bin=new TMemoryStream(); bin->LoadFromFile(OpenDialog1->FileName); int dwSize=bin->Size; Byte *pixel=new BYTE[dwSize]; bin->Read(pixel, dwSize); Graphics::TBitmap *bmp = new Graphics::TBitmap(); bmp->PixelFormat=pf24bit; bmp->Height=height; bmp->Width=width; for(int y=0; yScanLine[y]; for(int x=0; xPicture->Assign(bmp); delete bmp; delete bin; } }

感謝 的確快非常非常多 另外請問一下 Image1->Picture->Assign(bmp); 跟 Image1->Canvas->Draw(0,0,bmp); 差異在什麼地方

引言: 感謝 的確快非常非常多 另外請問一下 Image1->Picture->Assign(bmp); 跟 Image1->Canvas->Draw(0,0,bmp); 差異在什麼地方

前者：(TPicture::Assign) Copies one object to another by copying the contents of that object to the other. When Source is a object type that is valid for the Graphic property, Assign makes that graphic the value of the Graphic property. The actions performed by Assign depend on the actual types of the TPicture Graphic property and Source. For example, if the Graphic property and Source are bitmaps (TBitmap), the bitmap contained in Source is copied into the Graphic property. 後者：(TCanvas::Draw) Renders the graphic specified by the Graphic parameter on the canvas at the location given by the coordinates (X, Y). Call Draw to draw a graphic on the canvas. Draw calls the Draw method of the graphic. The image is rendered into a rectangle determined by the size of the graphic, with the upper left corner at the point (X, Y).

節錄自 Borland C   Builder Help

發表人 -

插個花  改這樣會更快    

void __fastcall TForm1::Button1Click(TObject *Sender)
{
  int width=217;
  int height=390;
  Byte *ptr;      if(OpenDialog1->Execute())
  {
    TMemoryStream* bin=new TMemoryStream();
    bin->LoadFromFile(OpenDialog1->FileName);
    int dwSize=bin->Size;
    Byte *pixel=new BYTE[dwSize];
    bin->Read(pixel, dwSize);        Graphics::TBitmap *bmp = new Graphics::TBitmap();
    bmp->PixelFormat=pf24bit;
    bmp->Height=height;
    bmp->Width=width;

    int  w2=0;        for(int y=0,w2=0; yScanLine[y];
      for(int x=0; xPicture->Assign(bmp);
    delete bmp;
    delete bin;
  }
}

這樣改的話..即使1600x1200也是很快的 不過為什麼只做灰階? 發表人 - 綾小路 於 2004/09/24 15:04:47

那請問, pixel這個東西要在哪裡delete ?    

引言: 插個花 改這樣會更快

void __fastcall TForm1::Button1Click(TObject *Sender)
{
  int width=217;
  int height=390;
  Byte *ptr;      if(OpenDialog1->Execute())
  {
    TMemoryStream* bin=new TMemoryStream();
    bin->LoadFromFile(OpenDialog1->FileName);
    int dwSize=bin->Size;
    Byte *pixel=new BYTE[dwSize];
    bin->Read(pixel, dwSize);        Graphics::TBitmap *bmp = new Graphics::TBitmap();
    bmp->PixelFormat=pf24bit;
    bmp->Height=height;
    bmp->Width=width;

    int  w2=0;        for(int y=0,w2=0; yScanLine[y];
      for(int x=0; xPicture->Assign(bmp);
    delete bmp;
    delete bin;
  }
}

這樣改的話..即使1600x1200也是很快的 不過為什麼只做灰階? 發表人 - 綾小路 於 2004/09/24 15:04:47