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- /******************************************************************************
- * $Id: gdal_simplesurf.h fe2d81c8819bf9794bce0210098e637565728350 2018-05-06 00:49:51 +0200 Even Rouault $
- * Project: GDAL
- * Purpose: Correlator
- * Author: Andrew Migal, migal.drew@gmail.com
- *
- ******************************************************************************
- * Copyright (c) 2012, Andrew Migal
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included
- * in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
- * DEALINGS IN THE SOFTWARE.
- ****************************************************************************/
-
- /**
- * @file
- * @author Andrew Migal migal.drew@gmail.com
- * @brief Class for searching corresponding points on images.
- */
-
- #ifndef GDALSIMPLESURF_H_
- #define GDALSIMPLESURF_H_
-
- #include "gdal_priv.h"
- #include "cpl_conv.h"
- #include <list>
-
- /**
- * @brief Class of "feature point" in raster. Used by SURF-based algorithm.
- *
- * @details This point presents coordinates of distinctive pixel in image.
- * In computer vision, feature points - the most "strong" and "unique"
- * pixels (or areas) in picture, which can be distinguished from others.
- * For more details, see FAST corner detector, SIFT, SURF and similar algorithms.
- */
- class GDALFeaturePoint
- {
- public:
- /**
- * Standard constructor. Initializes all parameters with negative numbers
- * and allocates memory for descriptor.
- */
- GDALFeaturePoint();
-
- /**
- * Copy constructor
- * @param fp Copied instance of GDALFeaturePoint class
- */
- GDALFeaturePoint(const GDALFeaturePoint& fp);
-
- /**
- * Create instance of GDALFeaturePoint class
- *
- * @param nX X-coordinate (pixel)
- * @param nY Y-coordinate (line)
- * @param nScale Scale which contains this point (2, 4, 8, 16 and so on)
- * @param nRadius Half of the side of descriptor area
- * @param nSign Sign of Hessian determinant for this point
- *
- * @note This constructor normally is invoked by SURF-based algorithm,
- * which provides all necessary parameters.
- */
- GDALFeaturePoint(int nX, int nY, int nScale, int nRadius, int nSign);
- virtual ~GDALFeaturePoint();
-
- /** Assignment operator */
- GDALFeaturePoint& operator=(const GDALFeaturePoint& point);
-
- /**
- * Provide access to point's descriptor.
- *
- * @param nIndex Position of descriptor's value.
- * nIndex should be within range from 0 to DESC_SIZE (in current version - 64)
- *
- * @return Reference to value of descriptor in 'nIndex' position.
- * If index is out of range then behaviour is undefined.
- */
- double& operator[](int nIndex);
-
- /** Descriptor length */
- static const int DESC_SIZE = 64;
-
- /**
- * Fetch X-coordinate (pixel) of point
- *
- * @return X-coordinate in pixels
- */
- int GetX() const;
-
- /**
- * Set X coordinate of point
- *
- * @param nX X coordinate in pixels
- */
- void SetX(int nX);
-
- /**
- * Fetch Y-coordinate (line) of point.
- *
- * @return Y-coordinate in pixels.
- */
- int GetY() const;
-
- /**
- * Set Y coordinate of point.
- *
- * @param nY Y coordinate in pixels.
- */
- void SetY(int nY);
-
- /**
- * Fetch scale of point.
- *
- * @return Scale for this point.
- */
- int GetScale() const ;
-
- /**
- * Set scale of point.
- *
- * @param nScale Scale for this point.
- */
- void SetScale(int nScale);
-
- /**
- * Fetch radius of point.
- *
- * @return Radius for this point.
- */
- int GetRadius() const;
-
- /**
- * Set radius of point.
- *
- * @param nRadius Radius for this point.
- */
- void SetRadius(int nRadius);
-
- /**
- * Fetch sign of Hessian determinant of point.
- *
- * @return Sign for this point.
- */
- int GetSign() const;
-
- /**
- * Set sign of point.
- *
- * @param nSign Sign of Hessian determinant for this point.
- */
- void SetSign(int nSign);
-
- private:
- // Coordinates of point in image
- int nX;
- int nY;
- // --------------------
- int nScale;
- int nRadius;
- int nSign;
- // Descriptor array
- double *padfDescriptor;
- };
-
- /**
- * @author Andrew Migal migal.drew@gmail.com
- * @brief Integral image class (summed area table).
- * @details Integral image is a table for fast computing the sum of
- * values in rectangular subarea. In more detail, for 2-dimensional array
- * of numbers this class provides capability to get sum of values in
- * rectangular arbitrary area with any size in constant time.
- * Integral image is constructed from grayscale picture.
- */
- class GDALIntegralImage
- {
- CPL_DISALLOW_COPY_ASSIGN(GDALIntegralImage)
-
- public:
- GDALIntegralImage();
- virtual ~GDALIntegralImage();
-
- /**
- * Compute integral image for specified array. Result is stored internally.
- *
- * @param padfImg Pointer to 2-dimensional array of values
- * @param nHeight Number of rows in array
- * @param nWidth Number of columns in array
- */
- void Initialize(const double **padfImg, int nHeight, int nWidth);
-
- /**
- * Fetch value of specified position in integral image.
- *
- * @param nRow Row of this position
- * @param nCol Column of this position
- *
- * @return Value in specified position or zero if parameters are out of range.
- */
- double GetValue(int nRow, int nCol);
-
- /**
- * Get sum of values in specified rectangular grid. Rectangle is constructed
- * from left top point.
- *
- * @param nRow Row of left top point of rectangle
- * @param nCol Column of left top point of rectangle
- * @param nWidth Width of rectangular area (number of columns)
- * @param nHeight Height of rectangular area (number of rows)
- *
- * @return Sum of values in specified grid.
- */
- double GetRectangleSum(int nRow, int nCol, int nWidth, int nHeight);
-
- /**
- * Get value of horizontal Haar wavelet in specified square grid.
- *
- * @param nRow Row of left top point of square
- * @param nCol Column of left top point of square
- * @param nSize Side of the square
- *
- * @return Value of horizontal Haar wavelet in specified square grid.
- */
- double HaarWavelet_X(int nRow, int nCol, int nSize);
-
- /**
- * Get value of vertical Haar wavelet in specified square grid.
- *
- * @param nRow Row of left top point of square
- * @param nCol Column of left top point of square
- * @param nSize Side of the square
- *
- * @return Value of vertical Haar wavelet in specified square grid.
- */
- double HaarWavelet_Y(int nRow, int nCol, int nSize);
-
- /**
- * Fetch height of integral image.
- *
- * @return Height of integral image (number of rows).
- */
- int GetHeight();
-
- /**
- * Fetch width of integral image.
- *
- * @return Width of integral image (number of columns).
- */
- int GetWidth();
-
- private:
- double **pMatrix = nullptr;
- int nWidth = 0;
- int nHeight = 0;
- };
-
- /**
- * @author Andrew Migal migal.drew@gmail.com
- * @brief Class for computation and storage of Hessian values in SURF-based algorithm.
- *
- * @details SURF-based algorithm normally uses this class for searching
- * feature points on raster images. Class also contains traces of Hessian matrices
- * to provide fast computations.
- */
- class GDALOctaveLayer
- {
- CPL_DISALLOW_COPY_ASSIGN(GDALOctaveLayer)
-
- public:
- GDALOctaveLayer();
-
- /**
- * Create instance with provided parameters.
- *
- * @param nOctave Number of octave which contains this layer
- * @param nInterval Number of position in octave
- *
- * @note Normally constructor is invoked only by SURF-based algorithm.
- */
- GDALOctaveLayer(int nOctave, int nInterval);
- virtual ~GDALOctaveLayer();
-
- /**
- * Perform calculation of Hessian determinants and their signs
- * for specified integral image. Result is stored internally.
- *
- * @param poImg Integral image object, which provides all necessary
- * data for computation
- *
- * @note Normally method is invoked only by SURF-based algorithm.
- */
- void ComputeLayer(GDALIntegralImage *poImg);
-
- /**
- * Octave which contains this layer (1,2,3...)
- */
- int octaveNum;
- /**
- * Length of the side of filter
- */
- int filterSize;
- /**
- * Length of the border
- */
- int radius;
- /**
- * Scale for this layer
- */
- int scale;
- /**
- * Image width in pixels
- */
- int width;
- /**
- * Image height in pixels
- */
- int height;
- /**
- * Hessian values for image pixels
- */
- double **detHessians;
- /**
- * Hessian signs for speeded matching
- */
- int **signs;
- };
-
- /**
- * @author Andrew Migal migal.drew@gmail.com
- * @brief Class for handling octave layers in SURF-based algorithm.
- * @details Class contains OctaveLayers and provides capability to construct octave space and distinguish
- * feature points. Normally this class is used only by SURF-based algorithm.
- */
- class GDALOctaveMap
- {
- CPL_DISALLOW_COPY_ASSIGN( GDALOctaveMap )
-
- public:
- /**
- * Create octave space. Octave numbers are start with one. (1, 2, 3, 4, ... )
- *
- * @param nOctaveStart Number of bottom octave
- * @param nOctaveEnd Number of top octave. Should be equal or greater than OctaveStart
- */
- GDALOctaveMap(int nOctaveStart, int nOctaveEnd);
- virtual ~GDALOctaveMap();
-
- /**
- * Calculate Hessian values for octave space
- * (for all stored octave layers) using specified integral image
- * @param poImg Integral image instance which provides necessary data
- * @see GDALOctaveLayer
- */
- void ComputeMap(GDALIntegralImage *poImg);
-
- /**
- * Method makes decision that specified point
- * in middle octave layer is maximum among all points
- * from 3x3x3 neighbourhood (surrounding points in
- * bottom, middle and top layers). Provided layers should be from the same octave's interval.
- * Detects feature points.
- *
- * @param row Row of point, which is candidate to be feature point
- * @param col Column of point, which is candidate to be feature point
- * @param bot Bottom octave layer
- * @param mid Middle octave layer
- * @param top Top octave layer
- * @param threshold Threshold for feature point recognition. Detected feature point
- * will have Hessian value greater than this provided threshold.
- *
- * @return TRUE if candidate was evaluated as feature point or FALSE otherwise.
- */
- static bool PointIsExtremum(int row, int col, GDALOctaveLayer *bot,
- GDALOctaveLayer *mid, GDALOctaveLayer *top, double threshold);
-
- /**
- * 2-dimensional array of octave layers
- */
- GDALOctaveLayer ***pMap;
-
- /**
- * Value for constructing internal octave space
- */
- static const int INTERVALS = 4;
-
- /**
- * Number of bottom octave
- */
- int octaveStart;
-
- /**
- * Number of top octave. Should be equal or greater than OctaveStart
- */
- int octaveEnd;
- };
-
- /**
- * @author Andrew Migal migal.drew@gmail.com
- * @brief Class for searching corresponding points on images.
- * @details Provides capability for detection feature points
- * and finding equal points on different images.
- * Class implements simplified version of SURF algorithm (Speeded Up Robust Features).
- * As original, this realization is scale invariant, but sensitive to rotation.
- * Images should have similar rotation angles (maximum difference is up to 10-15 degrees),
- * otherwise algorithm produces incorrect and very unstable results.
- */
-
- class GDALSimpleSURF
- {
- private:
- /**
- * Class stores indexes of pair of point
- * and distance between them.
- */
- class MatchedPointPairInfo
- {
- public:
- MatchedPointPairInfo(int nInd_1, int nInd_2, double dfDist):
- ind_1(nInd_1), ind_2(nInd_2), euclideanDist(dfDist) {}
-
- int ind_1;
- int ind_2;
- double euclideanDist;
- };
-
- CPL_DISALLOW_COPY_ASSIGN( GDALSimpleSURF )
-
- public:
- /**
- * Prepare class according to specified parameters. Octave numbers affects
- * to amount of detected points and their robustness.
- * Range between bottom and top octaves also affects to required time of detection points
- * (if range is large, algorithm should perform more operations).
- * @param nOctaveStart Number of bottom octave. Octave numbers starts with one
- * @param nOctaveEnd Number of top octave. Should be equal or greater than OctaveStart
- *
- * @note
- * Every octave finds points with specific size. For small images
- * use small octave numbers, for high resolution - large.
- * For 1024x1024 images it's normal to use any octave numbers from range 1-6.
- * (for example, octave start - 1, octave end - 3, or octave start - 2, octave end - 2.)
- * For larger images, try 1-10 range or even higher.
- * Pay attention that number of detected point decreases quickly per octave
- * for particular image. Algorithm finds more points in case of small octave numbers.
- * If method detects nothing, reduce bottom bound of octave range.
- *
- * NOTICE that every octave requires time to compute. Use a little range
- * or only one octave if execution time is significant.
- */
- GDALSimpleSURF(int nOctaveStart, int nOctaveEnd);
- virtual ~GDALSimpleSURF();
-
- /**
- * Convert image with RGB channels to grayscale using "luminosity" method.
- * Result is used in SURF-based algorithm, but may be used anywhere where
- * grayscale images with nice contrast are required.
- *
- * @param red Image's red channel
- * @param green Image's green channel
- * @param blue Image's blue channel
- * @param nXSize Width of initial image
- * @param nYSize Height of initial image
- * @param padfImg Array for resulting grayscale image
- * @param nHeight Height of resulting image
- * @param nWidth Width of resulting image
- *
- * @return CE_None or CE_Failure if error occurs.
- */
- static CPLErr ConvertRGBToLuminosity(
- GDALRasterBand *red,
- GDALRasterBand *green,
- GDALRasterBand *blue,
- int nXSize, int nYSize,
- double **padfImg, int nHeight, int nWidth);
-
- /**
- * Find feature points using specified integral image.
- *
- * @param poImg Integral image to be used
- * @param dfThreshold Threshold for feature point recognition. Detected feature point
- * will have Hessian value greater than this provided threshold.
- *
- * @note Typical threshold's value is 0,001. But this value
- * can be various in each case and depends on image's nature.
- * For example, value can be 0.002 or 0.005.
- * Fill free to experiment with it.
- * If threshold is high, than number of detected feature points is small,
- * and vice versa.
- */
- std::vector<GDALFeaturePoint>*
- ExtractFeaturePoints(GDALIntegralImage *poImg, double dfThreshold);
-
- /**
- * Find corresponding points (equal points in two collections).
- *
- * @param poMatchPairs Resulting collection for matched points
- * @param poFirstCollect Points on the first image
- * @param poSecondCollect Points on the second image
- * @param dfThreshold Value from 0 to 1. Threshold affects to number of
- * matched points. If threshold is lower, amount of corresponding
- * points is larger, and vice versa
- *
- * @return CE_None or CE_Failure if error occurs.
- */
- static CPLErr MatchFeaturePoints(
- std::vector<GDALFeaturePoint*> *poMatchPairs,
- std::vector<GDALFeaturePoint> *poFirstCollect,
- std::vector<GDALFeaturePoint> *poSecondCollect,
- double dfThreshold);
-
- private:
- /**
- * Compute euclidean distance between descriptors of two feature points.
- * It's used in comparison and matching of points.
- *
- * @param firstPoint First feature point to be compared
- * @param secondPoint Second feature point to be compared
- *
- * @return Euclidean distance between descriptors.
- */
- static double GetEuclideanDistance(
- GDALFeaturePoint &firstPoint, GDALFeaturePoint &secondPoint);
-
- /**
- * Set provided distance values to range from 0 to 1.
- *
- * @param poList List of distances to be normalized
- */
- static void NormalizeDistances(std::list<MatchedPointPairInfo> *poList);
-
- /**
- * Compute descriptor for specified feature point.
- *
- * @param poPoint Feature point instance
- * @param poImg image where feature point was found
- */
- static void SetDescriptor(GDALFeaturePoint *poPoint, GDALIntegralImage *poImg);
-
- private:
- int octaveStart;
- int octaveEnd;
- GDALOctaveMap *poOctMap;
- };
-
- #endif /* GDALSIMPLESURF_H_ */
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