Replace Image in Pdf

I´m trying to replace Images in existing Pdf-documents.

I´ve tried using the PDFium Component Suite for FireMonkey.

With the following code i´ve managed to insert an image via the AddPicture-function. Unfortunately i can´t find a way to get the position of the existing image. Unfortunately the record TPdfImage only has the properties Width, Height and Data. Does someone have experience with those Components or done anything like this already?

procedure TForm1.Button1Click(Sender: TObject);
var
  I: Integer;
  lImage: TPdfImage;
begin
  FPdf1.FileName := 'C:\Path_To_Pdf.pdf';
  FPdf1.PageNumber := 1;
  FPdf1.Active := True;

  for I := 0 to FPdf1.ImageCount - 1 do
  begin
    lImage := FPdf1.Image[I];
  end;

  FPdf1.AddPicture(ImageControl1.Bitmap, 20, 20, 100, 100);
  FPdf1.SaveAs('C:\Path_To_Pdf_Images.pdf');
end;

I´ve found a solution for the problem. With PDFium you can iterate over the Objects in the Pdf and just check if the ObjectType is otImage.

With this sample i´m overriding all images in the pdf with the Bitmap in ImageControl1. I hope this might help someone else in the future.

procedure TForm1.Button1Click(Sender: TObject);
var
  I: Integer;
  lImage: TPdfImage;
  lPdfRectangle: TPdfRectangle;
  lBitmap: TBitmap;
begin
  FPdf1.FileName := '..\..\Test.pdf';
  FPdf1.PageNumber := 1;
  FPdf1.Active := True;

  for I := 0 to FPdf1.ImageCount - 1 do
  begin
    lImage := FPdf1.Image[I];
  end;

  for I := 0 to FPdf1.ObjectCount - 1 do
  begin
    if FPdf1.ObjectType[I] = TObjectType.otImage then
    begin
      lPdfRectangle := FPdf1.ObjectBounds[I];
      lBitmap := FPdf1.ObjectBitmap[I];

      FPdf1.AddPicture(ImageControl1.Bitmap, lPdfRectangle.Left, lPdfRectangle.Bottom,
          lPdfRectangle.Right - lPdfRectangle.Left, lPdfRectangle.Top - lPdfRectangle.Bottom);
    end;
  end;

  FPdf1.SaveAs('..\..\Test_replaced.pdf');
end;