Изменить размер Bitmap Оформил: DeeCo Автор: http://www.swissdelphicenter.ch ```{ This function resizes a bitmap calculating the average color of a rectangular area of pixels from source bitmap to a pixel or a rectangular area to target bitmap. It produces a soft-color and undistorsioned result image unlike the StretchDraw method I think that this method have a tenichal name, but I am not sure. As you can see, this function could be very optimized :p } procedure TFormConvertir.ResizeBitmap(imgo, imgd: TBitmap; nw, nh: Integer); var xini, xfi, yini, yfi, saltx, salty: single; x, y, px, py, tpix: integer; PixelColor: TColor; r, g, b: longint; function MyRound(const X: Double): Integer; begin Result := Trunc(x); if Frac(x) >= 0.5 then if x >= 0 then Result := Result + 1 else Result := Result - 1; // Result := Trunc(X + (-2 * Ord(X < 0) + 1) * 0.5); end; begin // Set target size imgd.Width := nw; imgd.Height := nh; // Calcs width & height of every area of pixels of the source bitmap saltx := imgo.Width / nw; salty := imgo.Height / nh; yfi := 0; for y := 0 to nh - 1 do begin // Set the initial and final Y coordinate of a pixel area yini := yfi; yfi := yini + salty; if yfi >= imgo.Height then yfi := imgo.Height - 1; xfi := 0; for x := 0 to nw - 1 do begin // Set the inital and final X coordinate of a pixel area xini := xfi; xfi := xini + saltx; if xfi >= imgo.Width then xfi := imgo.Width - 1; // This loop calcs del average result color of a pixel area // of the imaginary grid r := 0; g := 0; b := 0; tpix := 0; for py := MyRound(yini) to MyRound(yfi) do begin for px := MyRound(xini) to MyRound(xfi) do begin Inc(tpix); PixelColor := ColorToRGB(imgo.Canvas.Pixels[px, py]); r := r + GetRValue(PixelColor); g := g + GetGValue(PixelColor); b := b + GetBValue(PixelColor); end; end; // Draws the result pixel imgd.Canvas.Pixels[x, y] := rgb(MyRound(r / tpix), MyRound(g / tpix), MyRound(b / tpix) ); end; end; end;```
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