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Diffstat (limited to 'macros/extractFeatures.sci')
| -rw-r--r-- | macros/extractFeatures.sci | 168 |
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diff --git a/macros/extractFeatures.sci b/macros/extractFeatures.sci new file mode 100644 index 0000000..8147891 --- /dev/null +++ b/macros/extractFeatures.sci @@ -0,0 +1,168 @@ +function [featureVector, ValidPoints]=extractFeatures(image,points,class,varargin) +// This function is used to extract interest point descriptors +// +// Calling Sequence +// [features, validPoints] = extractFeatures(Image, points, Class, Name, Value... ) +// +// Parameters +// Image: Input Image, should be a 2-D grayscale. The Input Image should be real +// points: M-by-2 vector containing the list of Interest Points +// Class: The Name of the feature detecting algorithm used for interest point detection +// Method: The desired algorithm to be used for feature vector calculation +// Metric: M-by-1 vector containing the strength of eack interest Point +// BlockSize: An odd integer scalar for defining a square neighbourhood centered at each interest point for Block Detection Method +// Upright: Rotation Invariance Flag specified as a boolean 'True' or 'False'. Default Value: False(0) +// SURFSize: Length of SURF Feature Vector. Values: [64(default)|128] +// Orientation: M-by-1 vector containing the orientation of the detected feature in radians +// Axes: M-by-2 vector containing the axes length values detected for MSER Object +// Scale: M-by-1 vector containing the scale of detection of each Interest Point +// SignOfLaplacian: M-by-1 vector containing the values of Sign of Laplacian of a SURF Object +// features: M-by-N Feature Matrix containing M feature vectors each of length N +// validPoints: M-by-2 Matrix containing the set of valid points whose features have been extracted +// +// Description +// The function derives the descriptors from pixels surrounding an interest point, where each interest point specifies the location of the detected region center. +// +// Examples +// image = imread('sample.jpg'); +// [corners count metric] = detectHarrisFeatures(image); +// [features, valid_corners] = extractFeatures(image, corners, "Class", "cornerPoints", "Metric", metric); +// +// Authors +// Umang Agrawal +// Sridhar Reddy + + [lhs rhs]=argn(0); + if lhs>2 + error(msprintf(" Too many output arguments")); + elseif rhs>13 + error(msprintf(" Too many input arguments")); + end + imageList=mattolist(image); + + //default values + blockSize=0; + upright=1; + surfSize=64; + if (class=="cornerPoints" | class=="BRISKPoints") + method="FREAK"; + elseif (class=="MSERRegions" | class=="SURFPoints") + method="SURF"; + elseif (class=="Matrix") + method="Block"; + else + error(msprintf(" Invalid class type, check documentation for the list of valid types")); + end + + //Count to ensure argument called only once + count_metric=0,count_orientation,count_scale,count_axes,count_signOfLaplacian; + count_method=0, count_block=0, count_surf=0, count_upright=0; + + //Parsing input arguments + for i=1:rhs-3 + if (varargin(i)=="Metric") + if(count_metric==0) + i=i+1; + metric=varargin(i); + else + error(msprintf(" Metric argument has been called twice")); + end + elseif (varargin(i)=="Orientation") + if(count_orientation==0) + i=i+1; + orientation=varargin(i); + else + error(msprintf(" Orientation argument has been called twice")); + end + elseif (varargin(i)=="Scale") + if(count_scale==0) + i=i+1; + scale=varargin(i); + else + error(msprintf(" Scale argument has been called twice")); + end + elseif (varargin(i)=="Axes") + if(count_axes==0) + i=i+1; + axes=varargin(i); + else + error(msprintf(" Axes argument has been called twice")); + end + elseif (varargin(i)=="SignOfLaplacian") + if(count_signOfLaplacian==0) + i=i+1; + signOfLaplacian=varargin(i); + else + error(msprintf("SignOfLaplacian argument has been called twice")); + end + elseif (varargin(i)=="Method") + if(count_method==0) + i=i+1; + method=varargin(i); + else + error(msprintf("Method argument has been called twice")); + end + elseif (varargin(i)=="BlockSize") + if(count_block==0) + i=i+1; + blockSize=varargin(i); + else + error(msprintf("BlockSize argument has been called twice")); + end + elseif (varargin(i)=="SurfSize") + if(count_surf==0) + i=i+1; + surfSize=varargin(i); + else + error(msprintf("SurfSize argument has been called twice")); + end + elseif (varargin(i)=="Upright") + if(count_upright==0) + i=i+1; + upright=varargin(i); + else + error(msprintf("Upright argument has been called twice")); + end + else + error(msprintf("Wrong argument, check documentation for the list of valid arguments")); + end + end + + + select class + case "cornerPoints" then + if(count_metric==0) + error(msprintf("For cornerPoints Class Metric argument is necessary")); + end + [featureVectors ValidPoints numBits numFeatures count metric]=extractFeatures(imageList, points, "Class", class, "Method", method, "surfSize", surfSize, "blockSize", blockSize, "upright", upright, "Metric",metric); + + case "BRISKPoints" then + if(count_metric==0 | count_scale==0 | count_orientation==0) + error(msprintf("For BRISKPoints Class Metric, Orientation and Scale arguments are necessary")); + end + [featureVectors ValidPoints numBits numFeatures scale metrix orientation count]=extractFeatures(imageList, points, "Class", class, "Method", method, "surfSize", surfSize, "blockSize", blockSize, "upright", upright, "Metric",metric,"Orientation",orientation,"Scale",scale); + + case "MSERRegions" then + if( count_orientation==0 | count_axes==0) + error(msprintf("For MSERRegions Class Orientation Matrix and Axes Matrix arguments are necessary.")); + end + [featureVectors ValidPoints numBits numFeatures count axes orientation]=extractFeatures(imageList, points, "Class", class, "Method", method, "surfSize", surfSize, "blockSize", blockSize, "upright", upright, "Metric",metric,"Orientation",orientation,"Axes",axes); + + case "SURFPoints" then + if(count_scale==0 | count_metric==0 | count_signOfLaplacian==0 | count_orientation==0) + error(msprintf("For SURFPoints Class Metric, Orientation, Scale and SignOfLaplacian arguments are necessary")); + end + [featureVectors ValidPoints numBits numFeatures count scale metrix signOfLaplacian orientation]=extractFeatures(imageList, points, "Class", class, "Method", method, "surfSize", surfSize, "blockSize", blockSize, "upright", upright, "Metric",metric,"Orientation",orientation,"Scale",scale,"SignOfLaplacian",signOfLaplacian); + + case "Matrix" then + if(count_block==0) + error(msprintf("For Matrix Class BlockSize argument is necessary")); + end + [featureVectors ValidPoints numBits numFeatures]=extractFeatures(imageList, points, "Class", class, "Method", method, "surfSize", surfSize, "blockSize", blockSize, "upright", upright,"BlockSize",blockSize); + end + + + + featureVector=struct("Type","binaryFeatures",'Features',featureVectors,'NumBits',numBits,'NumFeatures',numFeatures); + +endfunction |