Hi, this routine copies pixel data from a buffer onto a TBitmap.RawImage.Data structure.

var
  PixelPtr: PByte;
  PixelRowPtr: PByte;
begin
  PixelRowPtr := Fbmp.RawImage.Data;
  for Y := 0 to Self.Height - 1 do
  begin
    PixelPtr := PixelRowPtr;
    for X := 0 to Self.Width - 1 do
    begin
      PixelPtr^ := lRed;
      Inc(PixelPtr, 1);
      PixelPtr^ := lGreen;
      Inc(PixelPtr, 1);
      PixelPtr^ := lBlue;
      Inc(PixelPtr, 1);
      PixelPtr^ := 255;
      Inc(PixelPtr, 1);
    end;
    Inc(PixelRowPtr, FBmp.RawImage.Description.BytesPerLine);
  end;
end;

I've found it's very slow (in terms of milliseconds) when the TBitmap is bigger. What I can do to make it faster?.

P.S.: as you can see, I removed the way lRed, lGreen and lBlue are calculated, because that won't change the overall speed of the routine.

-
Leonardo M. Ram?
http://leonardorame.blogspot.com

Assign all the RGBA value in one go, that would reduce the inner loop by 4 times. i.e.:

var
  PixelPtr: PLongWord;
  PixelRowPtr: PByte;
begin
  PixelRowPtr := Fbmp.RawImage.Data;
  for Y := 0 to Self.Height - 1 do
  begin
    PixelPtr := PLongWord(PixelRowPtr);
    for X := 0 to (Self.Width - 1) div 4 do
    begin
      PixelPtr^ := (lRed shl 24) or (lGreen shl 16) or (lBlue shl 8) or 255;
      Inc(PixelPtr);
    end;
    Inc(PixelRowPtr, FBmp.RawImage.Description.BytesPerLine);
  end;
end;

Great!, I'll try it.

Well, it's speed improved, but the image is blue... Do you know why?.

The Longword is saved low byte first on a LE arch. You need to change the order of the colors to
PixelPtr^ := lRed or (lGreen shl 8) or (lBlue shl 16) or ($ff shl 24); Also make sure lRed, etc are bytes. If not use (lRed and $ff) etc.

Ludo

Yes!, now it works. Thank you and Leledumbo, it works pretty fast.