Grafiken erkennen. Library ?

[Aphton]

Hier, die einfache Variante mit SAD (Sum of Absolute Differences (siehe Wikipedia))

Delphi-Quellcode:

function findPicture(const Source, Picture: TBitmap): TPoint;
type
  TPRGBTripleRow = Array of PRGBTriple;
var
  SourceScanlineRow   : TPRGBTripleRow;
  PictureScanlineRow  : TPRGBTripleRow;
  function getRGBDifference(const ColorA, ColorB: PRGBTriple): Integer;
  begin
    Result := abs(ColorA.rgbtBlue   - ColorB.rgbtBlue)  +
              abs(ColorA.rgbtGreen  - ColorB.rgbtGreen) +
              abs(ColorA.rgbtRed    - ColorB.rgbtRed);
  end;
  function getPColor(const ScanlineRow: TPRGBTripleRow; const X, Y: Integer): PRGBTriple;
  begin
    Result := PRGBTriple(Integer(ScanlineRow[y]) + x * 3);
  end;
  procedure buildScanlineRows;
  var
    y: Integer;
  begin
    SetLength(SourceScanlineRow, Source.Height);
    for y := 0 to Source.Height - 1 do SourceScanlineRow[y] := Source.ScanLine[y];
    SetLength(PictureScanlineRow, Picture.Height);
    for y := 0 to Picture.Height - 1 do PictureScanlineRow[y] := Picture.ScanLine[y];
  end;
  function _findPicture: TPoint;
  var
    x, y, i, j  : Integer;
    SAD         : Integer;
    curSAD      : Integer;
  begin
    SAD := -1; // not assigned
    for y := 0 to Source.Height - Picture.Height do
      for x := 0 to Source.Width - Picture.Width do
      begin
        curSAD := 0;
        for j := 0 to Picture.Height - 1 do
          for i := 0 to Picture.Width - 1 do
            inc(curSAD, getRGBDifference(getPColor(SourceScanlineRow, x + i, y + j), getPColor(PictureScanlineRow, i, j)));
        if (SAD = -1) or (curSAD < SAD) then
        begin
          SAD     := curSAD;
          Result  := Point(x, y);
          if SAD = 0 then Exit;
        end;
      end;
  end;
begin
  if (Picture.Width > Source.Width) or (Picture.Height > Source.Height) or
     (Picture.PixelFormat <> pf24bit) or (Source.PixelFormat <> pf24bit) then
    Result := Point(-1, -1)
  else
  begin
    buildScanlineRows;
    Result := _findPicture;
  end;
end;

Edit: Das liefert die linke obere Ecke des Bereiches. Der Bereich hat klarerweise dieselbe Dimension wie "Picture"