#include <visp3/detection/vpDetectorFace.h>

Inheritance diagram for vpDetectorFace:

Public Member Functions
	vpDetectorFace ()

virtual	~vpDetectorFace ()

void	setCascadeClassifierFile (const std::string &filename)

bool	detect (const vpImage< unsigned char > &I)

std::vector< std::vector< vpImagePoint > > &	getPolygon ()

std::vector< vpImagePoint > &	getPolygon (size_t i)

std::string &	getMessage (size_t i)

std::vector< std::string > &	getMessage ()

size_t	getNbObjects () const

vpImagePoint	getCog (size_t i) const

vpRect	getBBox (size_t i) const

Protected Attributes
std::vector< cv::Rect >	m_faces

cv::CascadeClassifier	m_face_cascade

cv::Mat	m_frame_gray

std::vector< std::vector< vpImagePoint > >	m_polygon

std::vector< std::string >	m_message

size_t	m_nb_objects

Detailed Description

The vpDetectorFace class is a wrapper over OpenCV Haar cascade face detection capabilities. To use this class ViSP should be build against OpenCV 2.2.0 or a more recent version.

The following sample code shows how to use this class to detect the largest face in the image. The cascade classifier file "haarcascade_frontalface_alt.xml" can be found in ViSP source code or in OpenCV.

#include <visp3/detection/vpDetectorFace.h>
int main()
{
  vpImage<unsigned char> I;
  vpDetectorFace face_detector;
  face_detector.setCascadeClassifierFile("haarcascade_frontalface_alt.xml");
  while(1) {
    // acquire a new image in I
    bool face_found = face_detector.track(I);
    if (face_found) {
      vpRect face_bbox = face_detector.getBoundingBox(0); // largest face has index 0
    }
  }
}

A more complete example that works with images acquired from a camera is provided in tutorial-face-detector-live.cpp.

Examples:: tutorial-face-detector-live.cpp, and tutorial-face-detector.cpp.

Definition at line 80 of file vpDetectorFace.h.

Constructor & Destructor Documentation

vpDetectorFace::vpDetectorFace ( )

Default constructor.

Definition at line 54 of file vpDetectorFace.cpp.

virtual vpDetectorFace::~vpDetectorFace ( )

inlinevirtual

Default destructor.

Definition at line 92 of file vpDetectorFace.h.

Member Function Documentation

bool vpDetectorFace::detect ( const vpImage< unsigned char > & I )

virtual

Allows to detect a face in the image. When more than one face is detected, faces are sorted from largest to smallest.

Parameters

I	: Input image to process.

Returns: true if one or more faces are found, false otherwise.

The number of detected faces is returned using getNbObjects(). If a face is found the functions getBBox(), getCog() return some information about the location of the face.

The largest face is always available using getBBox(0) or getCog(0).

Implements vpDetectorBase.

Examples:: tutorial-face-detector-live.cpp, and tutorial-face-detector.cpp.

Definition at line 82 of file vpDetectorFace.cpp.

References vpImageConvert::convert(), m_face_cascade, m_faces, m_frame_gray, vpDetectorBase::m_message, vpDetectorBase::m_nb_objects, and vpDetectorBase::m_polygon.

vpRect vpDetectorBase::getBBox ( size_t i ) const

inherited

Return the bounding box of the ith object.

Examples:: tutorial-barcode-detector-live.cpp, tutorial-barcode-detector.cpp, tutorial-face-detector-live.cpp, and tutorial-face-detector.cpp.

Definition at line 89 of file vpDetectorBase.cpp.

References vpDetectorBase::m_polygon.

vpImagePoint vpDetectorBase::getCog ( size_t i ) const

inherited

Return the center of gravity location of the ith object.

Definition at line 75 of file vpDetectorBase.cpp.

References vpDetectorBase::m_polygon.

std::string & vpDetectorBase::getMessage ( size_t i )

inherited

Returns the contained message of the ith object if there is one.

Examples:: tutorial-barcode-detector-live.cpp, tutorial-barcode-detector.cpp, tutorial-face-detector-live.cpp, and tutorial-face-detector.cpp.

Definition at line 63 of file vpDetectorBase.cpp.

References vpException::badValue, vpDetectorBase::m_message, and vpDetectorBase::m_polygon.

std::vector< std::string >& vpDetectorBase::getMessage ( void )

inlineinherited

Returns the contained message of the ith object if there is one.

Definition at line 105 of file vpDetectorBase.h.

size_t vpDetectorBase::getNbObjects ( ) const

inlineinherited

Return the number of objects that are detected.

Examples:: tutorial-barcode-detector-live.cpp, tutorial-barcode-detector.cpp, tutorial-face-detector-live.cpp, and tutorial-face-detector.cpp.

Definition at line 110 of file vpDetectorBase.h.

std::vector< std::vector<vpImagePoint> >& vpDetectorBase::getPolygon ( )

inlineinherited

Returns object container box as a vector of points.

Examples:: tutorial-barcode-detector-live.cpp, tutorial-barcode-detector.cpp, tutorial-face-detector-live.cpp, and tutorial-face-detector.cpp.

Definition at line 87 of file vpDetectorBase.h.

std::vector< vpImagePoint > & vpDetectorBase::getPolygon ( size_t i )

inherited

Returns ith object container box as a vector of points.

Definition at line 51 of file vpDetectorBase.cpp.

References vpException::badValue, and vpDetectorBase::m_polygon.

void vpDetectorFace::setCascadeClassifierFile ( const std::string & filename )

Set the name of the OpenCV cascade classifier file used for face detection.

Parameters

filename : Full path to access to the file. Such a file can be found in OpenCV. Within the last versions it was name "haarcascade_frontalface_alt.xml".