如何將兩個PNG合併在一起?我知道你不能使用PNGObject.Draw
,因爲它不會複製alpha轉換(我不確定,但它不起作用),所以需要自定義過程/函數。我不是來跟兩手空空,我有這樣的過程:在其他PNG上繪製PNG圖像
procedure MergePNGLayer(Layer1,Layer2: TPNGObject; Const aLeft,aTop:Integer);
var
x, y: Integer;
SL1, SL2, SLBlended : pRGBLine;
aSL1, aSL2, aSLBlended: PByteArray;
blendCoeff: single;
blendedPNG, Lay2buff: TPNGObject;
begin
blendedPNG:=TPNGObject.Create;
blendedPNG.Assign(Layer1);
Lay2buff:=TPNGObject.Create;
Lay2buff.Assign(Layer2);
SetPNGCanvasSize(Layer2,Layer1.Width,Layer1.Height,aLeft,aTop);
for y := 0 to Layer1.Height-1 do
begin
SL1 := Layer1.Scanline[y];
SL2 := Layer2.Scanline[y];
aSL1 := Layer1.AlphaScanline[y];
aSL2 := Layer2.AlphaScanline[y];
SLBlended := blendedPNG.Scanline[y];
aSLBlended := blendedPNG.AlphaScanline[y];
for x := 0 to Layer1.Width-1 do
begin
blendCoeff:=aSL1[x] * 100/255/100;
aSLBlended[x] := round(aSL2[x] + (aSL1[x]-aSL2[x]) * blendCoeff);
SLBlended[x].rgbtRed := round(SL2[x].rgbtRed + (SL1[x].rgbtRed-SL2[x].rgbtRed) * blendCoeff);
SLBlended[x].rgbtGreen := round(SL2[x].rgbtGreen + (SL1[x].rgbtGreen-SL2[x].rgbtGreen) * blendCoeff);
SLBlended[x].rgbtBlue := round(SL2[x].rgbtBlue + (SL1[x].rgbtBlue-SL2[x].rgbtBlue) * blendCoeff);
end;
end;
Layer1.Assign(blendedPNG);
Layer2.Assign(Lay2buff);
blendedPNG.Free;
Lay2buff.Free;
end;
但可悲的是它不工作應該如何,它的工作,但不正確的。當它將空圖像與加載的圖像合併在一起時,它可以很好地工作,但是當兩幅圖像都不是空的時候,這會使它們失去透明度。
procedure TForm1.FormClick(Sender: TObject);
var
PNG1, PNG2, PNG3, Dest: TPNGObject;
begin
PNG1 := TPNGObject.Create;
PNG2 := TPNGObject.Create;
PNG3 := TPNGObject.Create;
PNG1.LoadFromFile('Aero\TopLeft.png');//Width 10
PNG2.LoadFromFile('Aero\Top.png');//Width 200
PNG3.LoadFromFile('Aero\TopRight.png');//Width 10
Dest := TPNGObject.CreateBlank(COLOR_RGBALPHA, 16, 220, 10);
MergePNGLayer(Dest, PNG1, 0, 0);
MergePNGLayer(Dest, PNG2, 10, 0);
MergePNGLayer(Dest, PNG3, 210, 0);
Dest.SaveToFile('C:\OUT.PNG');
end;
通緝的結果:
實際結果:
我不知道,如果你能看到這些imgaes之間的差異,但你應該在打開這些PNG編輯器軟件,你會看到不同之處。所以我需要其他程序來合併PNG。順便提一句,我正在使用最新版本的PNGImage
。
謝謝,祝你有美好的一天!
您確定要'CreateBlank'與'一位深度= 16' 4個顏色通道? – TLama