TIEVisionImage.detectLines
Declaration
function detectLines(detector: TIEVisionLinesDetector = ievBinaryDescriptor): TIEVisionVectorScalarInt32; safecall;
Description
Detect lines using a Binary Descriptor or LSD Detector.
Parameter | Description |
detector | Detection algorithm to use |
Note: You can draw the lines to a canvas using
DrawLines | Demos\IEVision\LinesDetectVideo\LinesDetectVideo.dpr |
var
lines: TIEVisionVectorScalarInt32;
i: integer;
begin
ImageEnView1.IO.LoadFromFile('input.jpg');
lines := ImageEnView1.IEBitmap.GetIEVisionImage().detectLines(ievBinaryDescriptor);
// draw results
ImageEnView1.IEBitmap.PixelFormat := ie24RGB;
ImageEnView1.IEBitmap.Origin := ieboBOTTOMLEFT;
for i := 0 to lines.size() - 1 do
begin
with lines.getScalarInt32(i) do
begin
with ImageEnView1.IEBitmap.Canvas do
begin
Pen.Width := 2;
Pen.Color := TRGB2TColor(CreateRGB(Random(255), Random(255), Random(255)));
MoveTo(val[0], val[1]);
LineTo(val[2], val[3]);
end;
end;
end;
ImageEnView1.Update();
end;
Comparison of Line Detection Methods
// BINARY DESCRIPTOR
lines := ImageEnView1.IEBitmap.GetIEVisionImage().detectLines( ievBinaryDescriptor );
for i := 0 to lines.size() - 1 do
begin
sc := lines.getScalarInt32(i);
with ImageEnView1.IEBitmap.Canvas do
begin
Pen.Width := 2;
Pen.Color := clRed;
MoveTo( sc.val[0], sc.val[1] );
LineTo( sc.val[2], sc.val[3] );
end;
end;
ImageEnView1.Proc.TextOut( Align_Text_Near_Left, Align_Text_Near_Top, Format( 'Lines: %d', [ lines.size ]), 'Arial', 12, Text_Color, [fsBold] );
ImageEnView1.Update();
// LSD DETECTOR
lines := ImageEnView1.IEBitmap.GetIEVisionImage().detectLines( ievLSDDetector );
for i := 0 to lines.size() - 1 do
begin
sc := lines.getScalarInt32(i);
with ImageEnView1.IEBitmap.Canvas do
begin
Pen.Width := 2;
Pen.Color := clRed;
MoveTo( sc.val[0], sc.val[1] );
LineTo( sc.val[2], sc.val[3] );
end;
end;
ImageEnView1.Proc.TextOut( Align_Text_Near_Left, Align_Text_Near_Top, Format( 'Lines: %d', [ lines.size ]), 'Arial', 12, Text_Color, [fsBold] );
ImageEnView1.Update();
// HOUGH TRANSFORM
ImageEnView1.IEBitmap.PixelFormat := ie8g;
ImageEnView1.IEBitmap.GetIEVisionImage().blur( IEVisionSize(3, 3), IEVisionPoint(-1, -1) );
ImageEnView1.IEBitmap.GetIEVisionImage().canny( 50, 200, 3 );
lines := ImageEnView1.IEBitmap.GetIEVisionImage().houghLinesP( 1, PI / 180, 200, 100, 10 );
for i := 0 to lines.size() - 1 do
begin
sc := lines.getScalarInt32(i);
with ImageEnView1.IEBitmap.Canvas do
begin
Pen.Width := 2;
Pen.Color := clRed;
MoveTo( sc.val[0], sc.val[1] );
LineTo( sc.val[2], sc.val[3] );
end;
end;
ImageEnView1.Proc.TextOut( Align_Text_Near_Left, Align_Text_Near_Top, Format( 'Lines: %d', [ lines.size ]), 'Arial', 12, Text_Color, [fsBold] );
ImageEnView1.Update();