Geschwindigkeitsoptimierung von Code

[Thomas Bodenmann <th.bodenmann@XXXXXXX.ch>]

Hallo

Der folgende Code wird trotz Optimierungsversuchen mit "Compile[]" nicht
beschleunigt...

ShearX = Compile[{{img, _Integer, 2}, {shear, _Real}, {width, _Integer}, {height, _Integer}},
      tmp = img;
      Do[
        skew = shear*(y + 0.5);
        skewi = Floor[skew];
        skewf = FractionalPart[skew];
        oleft = 0;
        Do[
          pixel = tmp[[y + 1, (width - x) + 1]];
          left = Round[(1 - skewf)*pixel];
          pixel = pixel - left + oleft;
          tmp[[y + 1, (width - x + skewi) + 1]] = pixel;
          oleft = left,
          {x, 0, width - 1}
          ];
        tmp[[y + 1, skewi + 1]] = oleft,
        {y, 0, height - 1}
        ];
      tmp,
      {{skew, _Real}, {skewi, _Integer}, {skewf, _Real},
       {oleft, _Integer}, {pixel, _Integer},
       {left, _Integer}, {tmp, _Integer, 2}}
      ];

(Scherung eines Rasterbildes nach Paeth)

ImageShearX[img_, shear_, width_, height_] := Module[{nc, nr},
      ImageDimensions[img];
      {nr, nc} = ImageDimensions[img];
      tmp = PlanarImageData[img];
      MeshedImageData[
        ImageData[
          Developer`ToPackedArray[ShearX[N[#], shear, width, height] & /@ tmp[[1]]],
          PixelInterleave -> False,
          ColorFunction -> {RGBColor[#1, 0, 0] &, RGBColor[0, #1, 0] &, RGBColor[0, 0, #1] &}
          ]
        ]
      ];

Was kann ich tun?

Gruss, Thomas