HOG特征的MATLAB代码

function [imgHOGFeature, colLabels] = ImgHOGFeature2(database, Img, tueImg, SkipStep, BinNum, Angle, CellSize, filter_para) % compare with ImgHOGFeature, this function use Image data instead of image name if nargin<7 disp('Not enough parameters!'); return; end if nargin==8 filter_hsize=filter_para(1); filter_delta=filter_para(2); end %% Gamma/Colour Normalization % Img = imread(ImgPathName); Img = uint8(Img); if size(Img,3) == 3 G = rgb2gray(Img); else G = Img; end [height, width] = size(G); %% Gradient and Gradient angle Computation if filter_hsize == 0 [GradientX,GradientY] = gradient(double(G)); else h=fspecial('gaussian', filter_hsize, filter_delta); [GradientX, GradientY] = HOGGradient(double(G)); end % calculate the norm of gradient Gr = sqrt(GradientX.^2+GradientY.^2); % Calculate the angle index = find(GradientX == 0); GradientX(index) = 1e-5; YX = GradientY./GradientX; if Angle == 180, A = ((atan(YX)+(pi/2))*180)./pi; end if Angle == 360, A = ((atan2(GradientY,GradientX)+pi).*180)./pi; end %% Spatial / Orientation Binning nAngle = Angle/BinNum; IndTag = ceil(A./nAngle); xStepNum = floor((width-2*CellSize)/SkipStep+1); yStepNum = floor((height-2*CellSize)/SkipStep+1); overL = SkipStep; FeatDim = BinNum*4; imgHOGFeature = zeros(FeatDim, xStepNum*yStepNum); currFeat = zeros(FeatDim,1); colLabels = zeros(xStepNum*yStepNum,1); % BinHOG = inline('BinHOGFeature(blockGr, blockInd, CellSize, BinNum)', 'blockGr', 'blockInd', 'CellSize', 'BinNum'); for j=1:xStepNum for k=1:yStepNum x_Off = (j-1)*overL+1; y_Off = (k-1)*overL+1; % here we define each block have 4 cells blockGr = Gr(y_Off:y_Off+2*CellSize-1,x_Off:x_Off+2*CellSize-1); blockInd = IndTag(y_Off:y_Off+2*CellSize-1,x_Off:x_Off+2*CellSize-1); blockL = tueImg(y_Off:y_Off+2*CellSize-1,x_Off:x_Off+2*CellSize-1, :); % calculate the block tag and Grain of each pixel currFeat = BinHOGFeature(blockGr, blockInd, CellSize, BinNum); % calculate the feature of the block imgHOGFeature(:, (j-1)*yStepNum+k) = currFeat; if strcmp(database, 'Sowerby') colLabels((j-1)*yStepNum+k) = getpatchclassSowerby_full(blockL); elseif strcmp(database, 'Sowerby') colLabels((j-1)*yStepNum+k) = getpatchclassMSRC9_full(blockL); else disp('DataBase define error!!!'); return; end end end