Fórum Diminuir resolução da imagem #374045

Ok.. ja consegui o que precisava
Vou postar aqui os codigos que usei.

Como a função de alterar a resolução era p bmp e as vezes posso ter q usar JPG, fiz (copiei no google) 2 funções para conversão.



[code:1:6e40917f84]procedure Bmp2Jpeg(const BmpFileName, JpgFileName: string);
var
Bmp: TBitmap;
Jpg: TJPEGImage;
begin
Bmp := TBitmap.Create;
Jpg := TJPEGImage.Create;
try
Bmp.LoadFromFile(BmpFileName);
Jpg.Assign(Bmp);
Jpg.SaveToFile(JpgFileName);
finally
Jpg.Free;
Bmp.Free;
end;
end;

procedure Jpeg2Bmp(const BmpFileName, JpgFileName: string);
var
Bmp: TBitmap;
Jpg: TJPEGImage;
begin
Bmp := TBitmap.Create;
Jpg := TJPEGImage.Create;
try
Jpg.LoadFromFile(JpgFileName);
Bmp.Assign(Jpg);
Bmp.SaveToFile(BmpFileName);
finally
Jpg.Free;
Bmp.Free;
end;
end;

procedure QualityResizeBitmap(bmpOrig, bmpDest: TBitmap; newWidth, newHeight: Integer);
var
xIni, xFin, yIni, yFin, xSalt, ySalt: Double;
X, Y, pX, pY, tpX: Integer;
R, G, B: Integer;
pxColor: TColor;
begin
bmpDest.Width := newWidth;
bmpDest.Height := newHeight;

xSalt := bmpOrig.Width / newWidth;
ySalt := bmpOrig.Height / newHeight;

yFin := 0;
for Y := 0 to pred(newHeight) do
begin
yIni := yFin;
yFin := yIni + ySalt;
if yFin >= bmpOrig.Height then
yFin := pred(bmpOrig.Height);

xFin := 0;
for X := 0 to pred(newWidth) do
begin
xIni := xFin;
xFin := xIni + xSalt;
if xFin >= bmpOrig.Width then
xFin := pred(bmpOrig.Width);

R := 0;
G := 0;
B := 0;
tpX := 0;

for pY := Round(yIni) to Round(yFin) do
for pX := Round(xIni) to Round(xFin) do
begin
Inc(tpX);
pxColor := ColorToRGB(bmpOrig.Canvas.Pixels[pX, pY&93;);
R := R + GetRValue(pxColor);
G := G + GetGValue(pxColor);
B := B + GetBValue(pxColor);
end;

bmpDest.Canvas.Pixels&91;X,Y&93; := RGB(Round(R/tpX),Round(G/tpX),Round(B/tpX));
end;
end;
end;
[/code:1:6e40917f84]

Se alguem precisar esta ae.
flw.