Data: 19/01/2011 16:58
De: Lindsay (loslds7@hotmail.com)
IP: 187.114.124.164
Assunto: Re: Comparar imagem
De: Lindsay (loslds7@hotmail.com)
IP: 187.114.124.164
Assunto: Re: Comparar imagem
function CompararImgs(Image1, Image2: TImage): Boolean;
var
b1, b2: TBitmap;
c1, c2: PByte;
x, y, i,
different, BytesPerPixel: Integer;
begin
b1 := Image1.Picture.Bitmap;
b2 := Image2.Picture.Bitmap;
Assert(b1.PixelFormat = b2.PixelFormat);
different := 0;
case b1.PixelFormat of
pf1bit, pf4bit, pf8bit: BytesPerPixel := 1;
pf15bit, pf16bit: BytesPerPixel := 2;
pf24bit: BytesPerPixel := 3;
pf32bit: BytesPerPixel := 4;
end;
for y := 0 to b1.Height - 1 do
begin
c1 := b1.Scanline[y];
c2 := b2.Scanline[y];
for x := 0 to b1.Width - 1 do
for i := 0 to BytesPerPixel - 1 do
begin
Inc(different, Integer(c1^ <> c2^));
Inc(c1);
Inc(c2);
end;
end;
Result := (different <> 0);
end;
/////////////////////////////
procedure TForm1.Button1Click(Sender: TObject);
var
b1, b2: TBitmap;
c1, c2: PByte;
x, y, i,
different: Integer; // Counter for different pixels
begin
b1 := Image1.Picture.Bitmap;
b2 := Image2.Picture.Bitmap;
Assert(b1.PixelFormat = b2.PixelFormat); // they have to be equal
different := 0;
for y := 0 to b1.Height - 1 do
begin
c1 := b1.Scanline[y];
c2 := b2.Scanline[y];
for x := 0 to b1.Width - 1 do
for i := 0 to BytesPerPixel - 1 do // 1, to 4, dep. on pixelformat
begin
Inc(different, Integer(c1^ <> c2^));
Inc(c1);
Inc(c2);
end;
end;
end;
//////////////////////////////////////
================
//esta rtorna em percentual a diferença
================
function BitmapDifference(BmpA, BmpB: TBitmap): double;
var
x, y: integer;
P, Q: PByte;
Diff: int64;
begin
if not assigned(BmpA) or not assigned(BmpB)
or (BmpA.PixelFormat <> pf24bit) or (BmpB.PixelFormat <> pf24bit)
or (BmpA.Width <> BmpB.Width) or (BmpA.Height <> BmpB.Height)
or (BmpA.Width * BmpA.Height = 0) then
raise Exception.Create('Cannot compare bitmaps');
Diff := 0;
for y := 0 to BmpA.Height - 1 do begin
P := BmpA.Scanline[y];
Q := BmpB.Scanline[y];
for x := 0 to BmpA.Width - 1 do begin
Diff := Diff + Sqr(P^ - Q^); inc(P); inc(Q);
Diff := Diff + Sqr(P^ - Q^); inc(P); inc(Q);
Diff := Diff + Sqr(P^ - Q^); inc(P); inc(Q);
end;
end;
Result := Sqrt(Diff / (BmpA.Width * BmpA.Height));
end;
================
