Click here to Skip to main content
15,896,118 members
Articles / Programming Languages / C++

Capturing Video from Web-camera on Windows 7 and 8 by using Media Foundation

Rate me:
Please Sign up or sign in to vote.
4.96/5 (25 votes)
10 Apr 2013CPOL5 min read 281.4K   33.1K   71  
Simple lib for capturing video from web-camera by using Media Foundation
/*M///////////////////////////////////////////////////////////////////////////////////////
//
//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
//  By downloading, copying, installing or using the software you agree to this license.
//  If you do not agree to this license, do not download, install,
//  copy or use the software.
//
//
//                           License Agreement
//                For Open Source Computer Vision Library
//
// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
// Third party copyrights are property of their respective owners.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
//   * Redistribution's of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//
//   * Redistribution's in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//
//   * The name of the copyright holders may not be used to endorse or promote products
//     derived from this software without specific prior written permission.
//
// This software is provided by the copyright holders and contributors "as is" and
// any express or implied warranties, including, but not limited to, the implied
// warranties of merchantability and fitness for a particular purpose are disclaimed.
// In no event shall the Intel Corporation or contributors be liable for any direct,
// indirect, incidental, special, exemplary, or consequential damages
// (including, but not limited to, procurement of substitute goods or services;
// loss of use, data, or profits; or business interruption) however caused
// and on any theory of liability, whether in contract, strict liability,
// or tort (including negligence or otherwise) arising in any way out of
// the use of this software, even if advised of the possibility of such damage.
//
//M*/

#ifndef __OPENCV_IMGPROC_IMGPROC_C_H__
#define __OPENCV_IMGPROC_IMGPROC_C_H__

#include "opencv2/core/core_c.h"
#include "opencv2/imgproc/types_c.h"

#ifdef __cplusplus
extern "C" {
#endif

/*********************** Background statistics accumulation *****************************/

/* Adds image to accumulator */
CVAPI(void)  cvAcc( const CvArr* image, CvArr* sum,
                   const CvArr* mask CV_DEFAULT(NULL) );

/* Adds squared image to accumulator */
CVAPI(void)  cvSquareAcc( const CvArr* image, CvArr* sqsum,
                         const CvArr* mask CV_DEFAULT(NULL) );

/* Adds a product of two images to accumulator */
CVAPI(void)  cvMultiplyAcc( const CvArr* image1, const CvArr* image2, CvArr* acc,
                           const CvArr* mask CV_DEFAULT(NULL) );

/* Adds image to accumulator with weights: acc = acc*(1-alpha) + image*alpha */
CVAPI(void)  cvRunningAvg( const CvArr* image, CvArr* acc, double alpha,
                          const CvArr* mask CV_DEFAULT(NULL) );

/****************************************************************************************\
*                                    Image Processing                                    *
\****************************************************************************************/

/* Copies source 2D array inside of the larger destination array and
   makes a border of the specified type (IPL_BORDER_*) around the copied area. */
CVAPI(void) cvCopyMakeBorder( const CvArr* src, CvArr* dst, CvPoint offset,
                              int bordertype, CvScalar value CV_DEFAULT(cvScalarAll(0)));

/* Smoothes array (removes noise) */
CVAPI(void) cvSmooth( const CvArr* src, CvArr* dst,
                      int smoothtype CV_DEFAULT(CV_GAUSSIAN),
                      int size1 CV_DEFAULT(3),
                      int size2 CV_DEFAULT(0),
                      double sigma1 CV_DEFAULT(0),
                      double sigma2 CV_DEFAULT(0));

/* Convolves the image with the kernel */
CVAPI(void) cvFilter2D( const CvArr* src, CvArr* dst, const CvMat* kernel,
                        CvPoint anchor CV_DEFAULT(cvPoint(-1,-1)));

/* Finds integral image: SUM(X,Y) = sum(x<X,y<Y)I(x,y) */
CVAPI(void) cvIntegral( const CvArr* image, CvArr* sum,
                       CvArr* sqsum CV_DEFAULT(NULL),
                       CvArr* tilted_sum CV_DEFAULT(NULL));

/*
   Smoothes the input image with gaussian kernel and then down-samples it.
   dst_width = floor(src_width/2)[+1],
   dst_height = floor(src_height/2)[+1]
*/
CVAPI(void)  cvPyrDown( const CvArr* src, CvArr* dst,
                        int filter CV_DEFAULT(CV_GAUSSIAN_5x5) );

/*
   Up-samples image and smoothes the result with gaussian kernel.
   dst_width = src_width*2,
   dst_height = src_height*2
*/
CVAPI(void)  cvPyrUp( const CvArr* src, CvArr* dst,
                      int filter CV_DEFAULT(CV_GAUSSIAN_5x5) );

/* Builds pyramid for an image */
CVAPI(CvMat**) cvCreatePyramid( const CvArr* img, int extra_layers, double rate,
                                const CvSize* layer_sizes CV_DEFAULT(0),
                                CvArr* bufarr CV_DEFAULT(0),
                                int calc CV_DEFAULT(1),
                                int filter CV_DEFAULT(CV_GAUSSIAN_5x5) );

/* Releases pyramid */
CVAPI(void)  cvReleasePyramid( CvMat*** pyramid, int extra_layers );


/* Filters image using meanshift algorithm */
CVAPI(void) cvPyrMeanShiftFiltering( const CvArr* src, CvArr* dst,
    double sp, double sr, int max_level CV_DEFAULT(1),
    CvTermCriteria termcrit CV_DEFAULT(cvTermCriteria(CV_TERMCRIT_ITER+CV_TERMCRIT_EPS,5,1)));

/* Segments image using seed "markers" */
CVAPI(void) cvWatershed( const CvArr* image, CvArr* markers );

/* Calculates an image derivative using generalized Sobel
   (aperture_size = 1,3,5,7) or Scharr (aperture_size = -1) operator.
   Scharr can be used only for the first dx or dy derivative */
CVAPI(void) cvSobel( const CvArr* src, CvArr* dst,
                    int xorder, int yorder,
                    int aperture_size CV_DEFAULT(3));

/* Calculates the image Laplacian: (d2/dx + d2/dy)I */
CVAPI(void) cvLaplace( const CvArr* src, CvArr* dst,
                      int aperture_size CV_DEFAULT(3) );

/* Converts input array pixels from one color space to another */
CVAPI(void)  cvCvtColor( const CvArr* src, CvArr* dst, int code );


/* Resizes image (input array is resized to fit the destination array) */
CVAPI(void)  cvResize( const CvArr* src, CvArr* dst,
                       int interpolation CV_DEFAULT( CV_INTER_LINEAR ));

/* Warps image with affine transform */
CVAPI(void)  cvWarpAffine( const CvArr* src, CvArr* dst, const CvMat* map_matrix,
                           int flags CV_DEFAULT(CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS),
                           CvScalar fillval CV_DEFAULT(cvScalarAll(0)) );

/* Computes affine transform matrix for mapping src[i] to dst[i] (i=0,1,2) */
CVAPI(CvMat*) cvGetAffineTransform( const CvPoint2D32f * src,
                                    const CvPoint2D32f * dst,
                                    CvMat * map_matrix );

/* Computes rotation_matrix matrix */
CVAPI(CvMat*)  cv2DRotationMatrix( CvPoint2D32f center, double angle,
                                   double scale, CvMat* map_matrix );

/* Warps image with perspective (projective) transform */
CVAPI(void)  cvWarpPerspective( const CvArr* src, CvArr* dst, const CvMat* map_matrix,
                                int flags CV_DEFAULT(CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS),
                                CvScalar fillval CV_DEFAULT(cvScalarAll(0)) );

/* Computes perspective transform matrix for mapping src[i] to dst[i] (i=0,1,2,3) */
CVAPI(CvMat*) cvGetPerspectiveTransform( const CvPoint2D32f* src,
                                         const CvPoint2D32f* dst,
                                         CvMat* map_matrix );

/* Performs generic geometric transformation using the specified coordinate maps */
CVAPI(void)  cvRemap( const CvArr* src, CvArr* dst,
                      const CvArr* mapx, const CvArr* mapy,
                      int flags CV_DEFAULT(CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS),
                      CvScalar fillval CV_DEFAULT(cvScalarAll(0)) );

/* Converts mapx & mapy from floating-point to integer formats for cvRemap */
CVAPI(void)  cvConvertMaps( const CvArr* mapx, const CvArr* mapy,
                            CvArr* mapxy, CvArr* mapalpha );

/* Performs forward or inverse log-polar image transform */
CVAPI(void)  cvLogPolar( const CvArr* src, CvArr* dst,
                         CvPoint2D32f center, double M,
                         int flags CV_DEFAULT(CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS));

/* Performs forward or inverse linear-polar image transform */
CVAPI(void)  cvLinearPolar( const CvArr* src, CvArr* dst,
                         CvPoint2D32f center, double maxRadius,
                         int flags CV_DEFAULT(CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS));

/* Transforms the input image to compensate lens distortion */
CVAPI(void) cvUndistort2( const CvArr* src, CvArr* dst,
                          const CvMat* camera_matrix,
                          const CvMat* distortion_coeffs,
                          const CvMat* new_camera_matrix CV_DEFAULT(0) );

/* Computes transformation map from intrinsic camera parameters
   that can used by cvRemap */
CVAPI(void) cvInitUndistortMap( const CvMat* camera_matrix,
                                const CvMat* distortion_coeffs,
                                CvArr* mapx, CvArr* mapy );

/* Computes undistortion+rectification map for a head of stereo camera */
CVAPI(void) cvInitUndistortRectifyMap( const CvMat* camera_matrix,
                                       const CvMat* dist_coeffs,
                                       const CvMat *R, const CvMat* new_camera_matrix,
                                       CvArr* mapx, CvArr* mapy );

/* Computes the original (undistorted) feature coordinates
   from the observed (distorted) coordinates */
CVAPI(void) cvUndistortPoints( const CvMat* src, CvMat* dst,
                               const CvMat* camera_matrix,
                               const CvMat* dist_coeffs,
                               const CvMat* R CV_DEFAULT(0),
                               const CvMat* P CV_DEFAULT(0));

/* creates structuring element used for morphological operations */
CVAPI(IplConvKernel*)  cvCreateStructuringElementEx(
            int cols, int  rows, int  anchor_x, int  anchor_y,
            int shape, int* values CV_DEFAULT(NULL) );

/* releases structuring element */
CVAPI(void)  cvReleaseStructuringElement( IplConvKernel** element );

/* erodes input image (applies minimum filter) one or more times.
   If element pointer is NULL, 3x3 rectangular element is used */
CVAPI(void)  cvErode( const CvArr* src, CvArr* dst,
                      IplConvKernel* element CV_DEFAULT(NULL),
                      int iterations CV_DEFAULT(1) );

/* dilates input image (applies maximum filter) one or more times.
   If element pointer is NULL, 3x3 rectangular element is used */
CVAPI(void)  cvDilate( const CvArr* src, CvArr* dst,
                       IplConvKernel* element CV_DEFAULT(NULL),
                       int iterations CV_DEFAULT(1) );

/* Performs complex morphological transformation */
CVAPI(void)  cvMorphologyEx( const CvArr* src, CvArr* dst,
                             CvArr* temp, IplConvKernel* element,
                             int operation, int iterations CV_DEFAULT(1) );

/* Calculates all spatial and central moments up to the 3rd order */
CVAPI(void) cvMoments( const CvArr* arr, CvMoments* moments, int binary CV_DEFAULT(0));

/* Retrieve particular spatial, central or normalized central moments */
CVAPI(double)  cvGetSpatialMoment( CvMoments* moments, int x_order, int y_order );
CVAPI(double)  cvGetCentralMoment( CvMoments* moments, int x_order, int y_order );
CVAPI(double)  cvGetNormalizedCentralMoment( CvMoments* moments,
                                             int x_order, int y_order );

/* Calculates 7 Hu's invariants from precalculated spatial and central moments */
CVAPI(void) cvGetHuMoments( CvMoments*  moments, CvHuMoments*  hu_moments );

/*********************************** data sampling **************************************/

/* Fetches pixels that belong to the specified line segment and stores them to the buffer.
   Returns the number of retrieved points. */
CVAPI(int)  cvSampleLine( const CvArr* image, CvPoint pt1, CvPoint pt2, void* buffer,
                          int connectivity CV_DEFAULT(8));

/* Retrieves the rectangular image region with specified center from the input array.
 dst(x,y) <- src(x + center.x - dst_width/2, y + center.y - dst_height/2).
 Values of pixels with fractional coordinates are retrieved using bilinear interpolation*/
CVAPI(void)  cvGetRectSubPix( const CvArr* src, CvArr* dst, CvPoint2D32f center );


/* Retrieves quadrangle from the input array.
    matrixarr = ( a11  a12 | b1 )   dst(x,y) <- src(A[x y]' + b)
                ( a21  a22 | b2 )   (bilinear interpolation is used to retrieve pixels
                                     with fractional coordinates)
*/
CVAPI(void)  cvGetQuadrangleSubPix( const CvArr* src, CvArr* dst,
                                    const CvMat* map_matrix );

/* Measures similarity between template and overlapped windows in the source image
   and fills the resultant image with the measurements */
CVAPI(void)  cvMatchTemplate( const CvArr* image, const CvArr* templ,
                              CvArr* result, int method );

/* Computes earth mover distance between
   two weighted point sets (called signatures) */
CVAPI(float)  cvCalcEMD2( const CvArr* signature1,
                          const CvArr* signature2,
                          int distance_type,
                          CvDistanceFunction distance_func CV_DEFAULT(NULL),
                          const CvArr* cost_matrix CV_DEFAULT(NULL),
                          CvArr* flow CV_DEFAULT(NULL),
                          float* lower_bound CV_DEFAULT(NULL),
                          void* userdata CV_DEFAULT(NULL));

/****************************************************************************************\
*                              Contours retrieving                                       *
\****************************************************************************************/

/* Retrieves outer and optionally inner boundaries of white (non-zero) connected
   components in the black (zero) background */
CVAPI(int)  cvFindContours( CvArr* image, CvMemStorage* storage, CvSeq** first_contour,
                            int header_size CV_DEFAULT(sizeof(CvContour)),
                            int mode CV_DEFAULT(CV_RETR_LIST),
                            int method CV_DEFAULT(CV_CHAIN_APPROX_SIMPLE),
                            CvPoint offset CV_DEFAULT(cvPoint(0,0)));

/* Initalizes contour retrieving process.
   Calls cvStartFindContours.
   Calls cvFindNextContour until null pointer is returned
   or some other condition becomes true.
   Calls cvEndFindContours at the end. */
CVAPI(CvContourScanner)  cvStartFindContours( CvArr* image, CvMemStorage* storage,
                            int header_size CV_DEFAULT(sizeof(CvContour)),
                            int mode CV_DEFAULT(CV_RETR_LIST),
                            int method CV_DEFAULT(CV_CHAIN_APPROX_SIMPLE),
                            CvPoint offset CV_DEFAULT(cvPoint(0,0)));

/* Retrieves next contour */
CVAPI(CvSeq*)  cvFindNextContour( CvContourScanner scanner );


/* Substitutes the last retrieved contour with the new one
   (if the substitutor is null, the last retrieved contour is removed from the tree) */
CVAPI(void)   cvSubstituteContour( CvContourScanner scanner, CvSeq* new_contour );


/* Releases contour scanner and returns pointer to the first outer contour */
CVAPI(CvSeq*)  cvEndFindContours( CvContourScanner* scanner );

/* Approximates a single Freeman chain or a tree of chains to polygonal curves */
CVAPI(CvSeq*) cvApproxChains( CvSeq* src_seq, CvMemStorage* storage,
                            int method CV_DEFAULT(CV_CHAIN_APPROX_SIMPLE),
                            double parameter CV_DEFAULT(0),
                            int  minimal_perimeter CV_DEFAULT(0),
                            int  recursive CV_DEFAULT(0));

/* Initalizes Freeman chain reader.
   The reader is used to iteratively get coordinates of all the chain points.
   If the Freeman codes should be read as is, a simple sequence reader should be used */
CVAPI(void) cvStartReadChainPoints( CvChain* chain, CvChainPtReader* reader );

/* Retrieves the next chain point */
CVAPI(CvPoint) cvReadChainPoint( CvChainPtReader* reader );


/****************************************************************************************\
*                            Contour Processing and Shape Analysis                       *
\****************************************************************************************/

/* Approximates a single polygonal curve (contour) or
   a tree of polygonal curves (contours) */
CVAPI(CvSeq*)  cvApproxPoly( const void* src_seq,
                             int header_size, CvMemStorage* storage,
                             int method, double eps,
                             int recursive CV_DEFAULT(0));

/* Calculates perimeter of a contour or length of a part of contour */
CVAPI(double)  cvArcLength( const void* curve,
                            CvSlice slice CV_DEFAULT(CV_WHOLE_SEQ),
                            int is_closed CV_DEFAULT(-1));

CV_INLINE double cvContourPerimeter( const void* contour )
{
    return cvArcLength( contour, CV_WHOLE_SEQ, 1 );
}


/* Calculates contour bounding rectangle (update=1) or
   just retrieves pre-calculated rectangle (update=0) */
CVAPI(CvRect)  cvBoundingRect( CvArr* points, int update CV_DEFAULT(0) );

/* Calculates area of a contour or contour segment */
CVAPI(double)  cvContourArea( const CvArr* contour,
                              CvSlice slice CV_DEFAULT(CV_WHOLE_SEQ),
                              int oriented CV_DEFAULT(0));

/* Finds minimum area rotated rectangle bounding a set of points */
CVAPI(CvBox2D)  cvMinAreaRect2( const CvArr* points,
                                CvMemStorage* storage CV_DEFAULT(NULL));

/* Finds minimum enclosing circle for a set of points */
CVAPI(int)  cvMinEnclosingCircle( const CvArr* points,
                                  CvPoint2D32f* center, float* radius );

/* Compares two contours by matching their moments */
CVAPI(double)  cvMatchShapes( const void* object1, const void* object2,
                              int method, double parameter CV_DEFAULT(0));

/* Calculates exact convex hull of 2d point set */
CVAPI(CvSeq*) cvConvexHull2( const CvArr* input,
                             void* hull_storage CV_DEFAULT(NULL),
                             int orientation CV_DEFAULT(CV_CLOCKWISE),
                             int return_points CV_DEFAULT(0));

/* Checks whether the contour is convex or not (returns 1 if convex, 0 if not) */
CVAPI(int)  cvCheckContourConvexity( const CvArr* contour );


/* Finds convexity defects for the contour */
CVAPI(CvSeq*)  cvConvexityDefects( const CvArr* contour, const CvArr* convexhull,
                                   CvMemStorage* storage CV_DEFAULT(NULL));

/* Fits ellipse into a set of 2d points */
CVAPI(CvBox2D) cvFitEllipse2( const CvArr* points );

/* Finds minimum rectangle containing two given rectangles */
CVAPI(CvRect)  cvMaxRect( const CvRect* rect1, const CvRect* rect2 );

/* Finds coordinates of the box vertices */
CVAPI(void) cvBoxPoints( CvBox2D box, CvPoint2D32f pt[4] );

/* Initializes sequence header for a matrix (column or row vector) of points -
   a wrapper for cvMakeSeqHeaderForArray (it does not initialize bounding rectangle!!!) */
CVAPI(CvSeq*) cvPointSeqFromMat( int seq_kind, const CvArr* mat,
                                 CvContour* contour_header,
                                 CvSeqBlock* block );

/* Checks whether the point is inside polygon, outside, on an edge (at a vertex).
   Returns positive, negative or zero value, correspondingly.
   Optionally, measures a signed distance between
   the point and the nearest polygon edge (measure_dist=1) */
CVAPI(double) cvPointPolygonTest( const CvArr* contour,
                                  CvPoint2D32f pt, int measure_dist );

/****************************************************************************************\
*                                  Histogram functions                                   *
\****************************************************************************************/

/* Creates new histogram */
CVAPI(CvHistogram*)  cvCreateHist( int dims, int* sizes, int type,
                                   float** ranges CV_DEFAULT(NULL),
                                   int uniform CV_DEFAULT(1));

/* Assignes histogram bin ranges */
CVAPI(void)  cvSetHistBinRanges( CvHistogram* hist, float** ranges,
                                int uniform CV_DEFAULT(1));

/* Creates histogram header for array */
CVAPI(CvHistogram*)  cvMakeHistHeaderForArray(
                            int  dims, int* sizes, CvHistogram* hist,
                            float* data, float** ranges CV_DEFAULT(NULL),
                            int uniform CV_DEFAULT(1));

/* Releases histogram */
CVAPI(void)  cvReleaseHist( CvHistogram** hist );

/* Clears all the histogram bins */
CVAPI(void)  cvClearHist( CvHistogram* hist );

/* Finds indices and values of minimum and maximum histogram bins */
CVAPI(void)  cvGetMinMaxHistValue( const CvHistogram* hist,
                                   float* min_value, float* max_value,
                                   int* min_idx CV_DEFAULT(NULL),
                                   int* max_idx CV_DEFAULT(NULL));


/* Normalizes histogram by dividing all bins by sum of the bins, multiplied by <factor>.
   After that sum of histogram bins is equal to <factor> */
CVAPI(void)  cvNormalizeHist( CvHistogram* hist, double factor );


/* Clear all histogram bins that are below the threshold */
CVAPI(void)  cvThreshHist( CvHistogram* hist, double threshold );


/* Compares two histogram */
CVAPI(double)  cvCompareHist( const CvHistogram* hist1,
                              const CvHistogram* hist2,
                              int method);

/* Copies one histogram to another. Destination histogram is created if
   the destination pointer is NULL */
CVAPI(void)  cvCopyHist( const CvHistogram* src, CvHistogram** dst );


/* Calculates bayesian probabilistic histograms
   (each or src and dst is an array of <number> histograms */
CVAPI(void)  cvCalcBayesianProb( CvHistogram** src, int number,
                                CvHistogram** dst);

/* Calculates array histogram */
CVAPI(void)  cvCalcArrHist( CvArr** arr, CvHistogram* hist,
                            int accumulate CV_DEFAULT(0),
                            const CvArr* mask CV_DEFAULT(NULL) );

CV_INLINE  void  cvCalcHist( IplImage** image, CvHistogram* hist,
                             int accumulate CV_DEFAULT(0),
                             const CvArr* mask CV_DEFAULT(NULL) )
{
    cvCalcArrHist( (CvArr**)image, hist, accumulate, mask );
}

/* Calculates back project */
CVAPI(void)  cvCalcArrBackProject( CvArr** image, CvArr* dst,
                                   const CvHistogram* hist );
#define  cvCalcBackProject(image, dst, hist) cvCalcArrBackProject((CvArr**)image, dst, hist)


/* Does some sort of template matching but compares histograms of
   template and each window location */
CVAPI(void)  cvCalcArrBackProjectPatch( CvArr** image, CvArr* dst, CvSize range,
                                        CvHistogram* hist, int method,
                                        double factor );
#define  cvCalcBackProjectPatch( image, dst, range, hist, method, factor ) \
     cvCalcArrBackProjectPatch( (CvArr**)image, dst, range, hist, method, factor )


/* calculates probabilistic density (divides one histogram by another) */
CVAPI(void)  cvCalcProbDensity( const CvHistogram* hist1, const CvHistogram* hist2,
                                CvHistogram* dst_hist, double scale CV_DEFAULT(255) );

/* equalizes histogram of 8-bit single-channel image */
CVAPI(void)  cvEqualizeHist( const CvArr* src, CvArr* dst );


/* Applies distance transform to binary image */
CVAPI(void)  cvDistTransform( const CvArr* src, CvArr* dst,
                              int distance_type CV_DEFAULT(CV_DIST_L2),
                              int mask_size CV_DEFAULT(3),
                              const float* mask CV_DEFAULT(NULL),
                              CvArr* labels CV_DEFAULT(NULL),
                              int labelType CV_DEFAULT(CV_DIST_LABEL_CCOMP));


/* Applies fixed-level threshold to grayscale image.
   This is a basic operation applied before retrieving contours */
CVAPI(double)  cvThreshold( const CvArr*  src, CvArr*  dst,
                            double  threshold, double  max_value,
                            int threshold_type );

/* Applies adaptive threshold to grayscale image.
   The two parameters for methods CV_ADAPTIVE_THRESH_MEAN_C and
   CV_ADAPTIVE_THRESH_GAUSSIAN_C are:
   neighborhood size (3, 5, 7 etc.),
   and a constant subtracted from mean (...,-3,-2,-1,0,1,2,3,...) */
CVAPI(void)  cvAdaptiveThreshold( const CvArr* src, CvArr* dst, double max_value,
                                  int adaptive_method CV_DEFAULT(CV_ADAPTIVE_THRESH_MEAN_C),
                                  int threshold_type CV_DEFAULT(CV_THRESH_BINARY),
                                  int block_size CV_DEFAULT(3),
                                  double param1 CV_DEFAULT(5));

/* Fills the connected component until the color difference gets large enough */
CVAPI(void)  cvFloodFill( CvArr* image, CvPoint seed_point,
                          CvScalar new_val, CvScalar lo_diff CV_DEFAULT(cvScalarAll(0)),
                          CvScalar up_diff CV_DEFAULT(cvScalarAll(0)),
                          CvConnectedComp* comp CV_DEFAULT(NULL),
                          int flags CV_DEFAULT(4),
                          CvArr* mask CV_DEFAULT(NULL));

/****************************************************************************************\
*                                  Feature detection                                     *
\****************************************************************************************/

/* Runs canny edge detector */
CVAPI(void)  cvCanny( const CvArr* image, CvArr* edges, double threshold1,
                      double threshold2, int  aperture_size CV_DEFAULT(3) );

/* Calculates constraint image for corner detection
   Dx^2 * Dyy + Dxx * Dy^2 - 2 * Dx * Dy * Dxy.
   Applying threshold to the result gives coordinates of corners */
CVAPI(void) cvPreCornerDetect( const CvArr* image, CvArr* corners,
                               int aperture_size CV_DEFAULT(3) );

/* Calculates eigen values and vectors of 2x2
   gradient covariation matrix at every image pixel */
CVAPI(void)  cvCornerEigenValsAndVecs( const CvArr* image, CvArr* eigenvv,
                                       int block_size, int aperture_size CV_DEFAULT(3) );

/* Calculates minimal eigenvalue for 2x2 gradient covariation matrix at
   every image pixel */
CVAPI(void)  cvCornerMinEigenVal( const CvArr* image, CvArr* eigenval,
                                  int block_size, int aperture_size CV_DEFAULT(3) );

/* Harris corner detector:
   Calculates det(M) - k*(trace(M)^2), where M is 2x2 gradient covariation matrix for each pixel */
CVAPI(void)  cvCornerHarris( const CvArr* image, CvArr* harris_responce,
                             int block_size, int aperture_size CV_DEFAULT(3),
                             double k CV_DEFAULT(0.04) );

/* Adjust corner position using some sort of gradient search */
CVAPI(void)  cvFindCornerSubPix( const CvArr* image, CvPoint2D32f* corners,
                                 int count, CvSize win, CvSize zero_zone,
                                 CvTermCriteria  criteria );

/* Finds a sparse set of points within the selected region
   that seem to be easy to track */
CVAPI(void)  cvGoodFeaturesToTrack( const CvArr* image, CvArr* eig_image,
                                    CvArr* temp_image, CvPoint2D32f* corners,
                                    int* corner_count, double  quality_level,
                                    double  min_distance,
                                    const CvArr* mask CV_DEFAULT(NULL),
                                    int block_size CV_DEFAULT(3),
                                    int use_harris CV_DEFAULT(0),
                                    double k CV_DEFAULT(0.04) );

/* Finds lines on binary image using one of several methods.
   line_storage is either memory storage or 1 x <max number of lines> CvMat, its
   number of columns is changed by the function.
   method is one of CV_HOUGH_*;
   rho, theta and threshold are used for each of those methods;
   param1 ~ line length, param2 ~ line gap - for probabilistic,
   param1 ~ srn, param2 ~ stn - for multi-scale */
CVAPI(CvSeq*)  cvHoughLines2( CvArr* image, void* line_storage, int method,
                              double rho, double theta, int threshold,
                              double param1 CV_DEFAULT(0), double param2 CV_DEFAULT(0));

/* Finds circles in the image */
CVAPI(CvSeq*) cvHoughCircles( CvArr* image, void* circle_storage,
                              int method, double dp, double min_dist,
                              double param1 CV_DEFAULT(100),
                              double param2 CV_DEFAULT(100),
                              int min_radius CV_DEFAULT(0),
                              int max_radius CV_DEFAULT(0));

/* Fits a line into set of 2d or 3d points in a robust way (M-estimator technique) */
CVAPI(void)  cvFitLine( const CvArr* points, int dist_type, double param,
                        double reps, double aeps, float* line );

#ifdef __cplusplus
}
#endif

#endif

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Software Developer
Australia Australia
This member has not yet provided a Biography. Assume it's interesting and varied, and probably something to do with programming.

Comments and Discussions