Seguimiento de personas, animales y objetos con OpenCV en Delphi

OpenCV para los que no la conozcan, es una biblioteca libre enfocada hacia la visión artificial, inicialmente desarrollada por Intel bajo licencia BSD lo que permite que sea usada libremente para un propósito comercial o de investigación.

OpenCV es multiplataforma con versiones para Windows, Linux y Mac y contiene funciones que tratan los temas de proceso de visión, reconocimiento facial, calibrado de cámaras o robótica.

Esta biblioteca es la base de la herramienta Swistrack que sirve para hacer un seguimiento de personas, animales y objetos.

El siguiente código se puede ejecutar en Delphi XE2 o superior y lo que hace es, como veis en la imagen, un seguimiento de las personas que circulan por la calle rodeándolas con un rectángulo de color rojo a medida que se van desplazando.

(* /*****************************************************************
// Delphi-OpenCV Demo
// Copyright (C) 2013 Project Delphi-OpenCV
// ****************************************************************
// Contributor:
// Mikhail Grigorev
// email: sleuthhound@gmail.com
// ****************************************************************
// You may retrieve the latest version of this file at the GitHub,
// located at git://github.com/Laex/Delphi-OpenCV.git
// ****************************************************************
// The contents of this file are used with permission, subject to
// the Mozilla Public License Version 1.1 (the "License"); you may
// not use this file except in compliance with the License. You may
// obtain a copy of the License at
// http://www.mozilla.org/MPL/MPL-1_1Final.html
//
// Software distributed under the License is distributed on an
// "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
// implied. See the License for the specific language governing
// rights and limitations under the License.
******************************************************************* *)

// JCL_DEBUG_EXPERT_GENERATEJDBG OFF
// JCL_DEBUG_EXPERT_INSERTJDBG OFF
// JCL_DEBUG_EXPERT_DELETEMAPFILE OFF
program MotionDetect;

{$APPTYPE CONSOLE}
{$POINTERMATH ON}
{$R *.res}

uses
System.SysUtils,
Math,
uLibName in '..\..\..\include\uLibName.pas',
highgui_c in '..\..\..\include\highgui\highgui_c.pas',
imgproc.types_c in '..\..\..\include\imgproc\imgproc.types_c.pas',
imgproc_c in '..\..\..\include\imgproc\imgproc_c.pas',
imgproc in '..\..\..\include\imgproc\imgproc.pas',
core in '..\..\..\include\core\core.pas',
core.types_c in '..\..\..\include\core\Core.types_c.pas',
core_c in '..\..\..\include\core\core_c.pas';

var
storage: pCvMemStorage = nil;
capture: pCvCapture = nil;
frame: pIplImage = nil;
frame_grey: pIplImage = nil;
difference_img: pIplImage = nil;
oldframe_grey: pIplImage = nil;
contours: pCvSeq = nil;
c: pCvSeq = nil;
// rect: TCvRect;
rect2d: TCvBox2D;
key: integer;
first: boolean = true;

begin
try
capture := cvCreateCameraCapture(0);
storage := cvCreateMemStorage(0);
frame := cvQueryFrame(capture);
frame_grey := cvCreateImage(cvSize(frame^.width, frame^.height), IPL_DEPTH_8U, 1);

while true do
begin
frame := cvQueryFrame(capture);
if frame = nil then
break;
cvCvtColor(frame, frame_grey, CV_RGB2GRAY);
if first then
begin
difference_img := cvCloneImage(frame_grey);
oldframe_grey := cvCloneImage(frame_grey);
cvConvertScale(frame_grey, oldframe_grey, 1.0, 0.0);
first := false;
end;
cvAbsDiff(oldframe_grey, frame_grey, difference_img);
cvSmooth(difference_img, difference_img, CV_BLUR);
cvThreshold(difference_img, difference_img, 25, 255, CV_THRESH_BINARY);
contours := AllocMem(SizeOf(TCvSeq));
cvFindContours(difference_img, storage, @contours, SizeOf(TCvContour), CV_RETR_LIST, CV_CHAIN_APPROX_NONE,
cvPoint(0, 0));
c := contours;
while (c <> nil) do
begin
rect2d := cvMinAreaRect2(c);
cvRectangle(frame, cvPoint(Round(rect2d.center.x - rect2d.size.width / 2),
Round(rect2d.center.y - rect2d.size.height / 2)), cvPoint(Round(rect2d.center.x + rect2d.size.width / 2),
Round(rect2d.center.y + rect2d.size.height / 2)), cvScalar(0, 0, 255, 0), 2, 8, 0);
c := c.h_next;
end;
cvShowImage('Output Image', frame);
cvShowImage('Difference Image', difference_img);
cvConvertScale(frame_grey, oldframe_grey, 1.0, 0.0);
cvClearMemStorage(storage);
c := nil;
FreeMem(contours, SizeOf(TCvSeq));
key := cvWaitKey(33);
if (key = 27) then
break;
end;
cvReleaseMemStorage(storage);
cvReleaseCapture(capture);
cvReleaseImage(oldframe_grey);
cvReleaseImage(difference_img);
cvReleaseImage(frame_grey);
cvDestroyAllWindows();
except
on E: Exception do
WriteLn(E.ClassName, ': ', E.Message);
end;

end.

Enlace  | Biblioteca Delphi OpenCV