Rotieren eines Bildes um 90°

Jansen

Grau ist alle Theorie.

TJPEGImage *jp = new TJPEGImage();
  try
  {
    jp->LoadFromFile("c:\\bild1.jpg");

    Graphics::TBitmap *tgtbmp = new Graphics::TBitmap();
    Graphics::TBitmap *srcbmp = new Graphics::TBitmap();

    srcbmp->Assign(jp);

    tgtbmp->Height = srcbmp->Width;
    tgtbmp->Width = srcbmp->Height;
    tgtbmp->PixelFormat = pf32bit;
    srcbmp->PixelFormat = tgtbmp->PixelFormat;

    int *tgtptr, *srcptr;
    for( int y = 0; y < tgtbmp->Height; y++)
    {
      tgtptr = (int*)tgtbmp->ScanLine[y];
      for(int x = 0; x < tgtbmp->Width; x++)
      {
        srcptr = (int*)srcbmp->ScanLine[x];
        tgtptr[x] = srcptr[y];
      }
    }
    Image1->Picture->Bitmap = tgtbmp;
    delete tgtbmp;
    delete srcbmp;
  }
  catch(Exception &E)
  {
    MessageBox(0, (E.Message).c_str(), String(E.ClassName()).c_str(), MB_ICONSTOP);
  }
  delete jp;

Warum hier nicht nur gedreht sondern auch noch gespiegelt wird solltest du mit etwas logischem Denken selbst herausbekommen. Schliesslich wollen wir es ja nicht zu einfach machen.

Habe auf einer Buch-CD noch 90°-Drehprogramm (WinApi nah) gefunden.
(Buch heisst "Borland Builder im Team")

void __fastcall TForm1::Button1Click(TObject *Sender)
{
HDC dc=GetDC(0);
TMemoryStream *astream;
astream = new TMemoryStream;
astream->SetSize(  sizeof (BITMAPINFOHEADER)
                 + Image1->Picture->Bitmap->Height
                  *((long)(Image1->Picture->Bitmap->Width+4) * 3));
TMemoryStream *bstream;
bstream = new TMemoryStream;
bstream->SetSize(  sizeof (BITMAPINFOHEADER)
                 + Image1->Picture->Bitmap->Height
                  *((long)(Image1->Picture->Bitmap->Width+4) * 3));
BITMAPINFOHEADER *bmih;
bmih = (BITMAPINFOHEADER*)astream->Memory;
bmih->biSize = 40;
bmih->biWidth = Image1->Picture->Bitmap->Width;
bmih->biHeight = Image1->Picture->Bitmap->Height;
bmih->biPlanes = 1;
bmih->biBitCount = 24;
bmih->biCompression = BI_RGB;
bmih->biSizeImage = 0;
bmih->biXPelsPerMeter = 10000;
bmih->biYPelsPerMeter = 10000;
bmih->biClrUsed =0;
bmih->biClrImportant =0;

bmih = (BITMAPINFOHEADER*)bstream->Memory;
bmih->biSize = 40;
bmih->biWidth = Image1->Picture->Bitmap->Height;
bmih->biHeight = Image1->Picture->Bitmap->Width;
bmih->biPlanes = 1;
bmih->biBitCount = 24;
bmih->biCompression = BI_RGB;
bmih->biSizeImage = 0;
bmih->biXPelsPerMeter = 10000;
bmih->biYPelsPerMeter = 10000;
bmih->biClrUsed =0;
bmih->biClrImportant =0;

unsigned char *aptr;
aptr = (unsigned char*)astream->Memory +sizeof (BITMAPINFOHEADER);
unsigned char *bptr;
bptr = (unsigned char*)bstream->Memory +sizeof (BITMAPINFOHEADER);

int I=GetDIBits(dc, Image1->Picture->Bitmap->Handle,
          0,Image1->Picture->Bitmap->Height,
          aptr,
          (BITMAPINFO*)astream->Memory, DIB_RGB_COLORS);

int linewidth = (Image1->Picture->Bitmap->Width*3);
linewidth = linewidth+(linewidth % 4==0?0:4-linewidth % 4);
int blinewidth = (Image1->Picture->Bitmap->Height*3);
blinewidth = blinewidth+(blinewidth % 4==0?0:4-blinewidth % 4);
if (I > 0)
 {
 int j,k;
 unsigned char *ptr1;
 unsigned char *ptr2;
 for (j=0;j<Image1->Picture->Bitmap->Height;j++)
  {
   for (k=0;k<Image1->Picture->Bitmap->Width;k++)
    {
     ptr1 = aptr +
       + j*linewidth
       + k * 3;
     ptr2 = bptr +
       + k* blinewidth
       + (Image1->Picture->Bitmap->Height -j) *3;
     memcpy(ptr2,ptr1,3);
    }
  }
 }
Image1->Picture->Bitmap->Handle =
CreateDIBitmap(dc,
           (BITMAPINFOHEADER*)bstream->Memory,
           CBM_INIT	,
           bptr,
           (BITMAPINFO*)bstream->Memory,
           DIB_RGB_COLORS);
astream->Free();
bstream->Free();
ReleaseDC(0,dc);
}

tolgaince

OK, danke ihr habt mir gut geholfen, mitlerweile klappt alles, bis dann

Gruß

Tolga