How to traverse pixels in Monochrome Bitmap (pf1bit)

Sir,
     Basically I want to traverse each pixel in a monochrome bitmap. I tried using PByteArray (for Scanline..) and to loop through the bitmap I've also given Bitmap.Width - 8.
But this method is not working. In Short I want to traverse each pixel, get color info for that pixel and do some calculations based on it,
Please Help me out.
Regards, Jagan
rjaganAsked:
Who is Participating?
 
DOsingaConnect With a Mentor Commented:
You might also have a try with the WinApi GetDIBits functions. This will allow you to copy the pixels of the bitmap in a format of your choice, to be specified in a passed TBitmapInfo.
0
 
MadshiCommented:
Hi Jagan,

you can either use the ScanLine property. Perhaps the following example from the delphi help file will help you with that...

The problem with this ScanLine property is that you have to bother with things like color depth.
So the example below works only with 256 color bitmaps.

procedure TForm1.Button1Click(Sender: TObject);

// Zeichnung direkt in das BitMap-Objekt ausgeben
var
  x,y : integer;
  BitMap : TBitMap;
  P : PByteArray;
begin
  BitMap := TBitMap.create;
  try
    BitMap.LoadFromFile('..\Images\Splash\256color\factory.bmp');
    for y := 0 to BitMap.height -1 do
    begin
      P := BitMap.ScanLine[y];
      for x := 0 to BitMap.width -1 do
        P[x] := y;
    end;
  canvas.draw(0,0,BitMap);
  finally
    BitMap.free;
  end;
end;

Or you could use the bitmap.canvas.pixels property, which is easier to use, but much much slower...

Regards, Madshi.
0
 
viktornetCommented:
YOu go pixel by pixel through the bitmap in order to get eac pixel and do some calculations top it...


for y := 0 to Bitmap.Height do
  for x := 0 to Bitmap.Width do
    bitmap.canvas.pixels[x, y] := bitmap.canvas.pixels[x, y] xor $fafafafa;

-Viktor
--Ivanov
0
 
rjaganAuthor Commented:
Thanks a lot for your consideration
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.