image_stitch.rar_matlab中surf算法_packmeq_surf_图像拼接SURF_联合开发网官

% 以图像集的方法加载图片 buildingDir = fullfile(toolboxdir('vision'), 'visiondata', 'building'); buildingScene = imageSet(buildingDir); % 显示要拼接的所有图片 montage(buildingScene.ImageLocation) % 从图片集中读取第一幅图像 I = read(buildingScene, 1); % 将图像转为灰度图，再提取I(1)的特征点，用的是surf算法。 grayImage = rgb2gray(I); points = detectSURFFeatures(grayImage); [features, points] = extractFeatures(grayImage, points); % 初始化所有变换的恒等矩阵。 tforms(buildingScene.Count) = projective2d(eye(3)); % Iterate over remaining image pairs for n = 2:buildingScene.Count % Store points and features for I(n-1). % 存储前一图像的特征点坐标和值。 pointsPrevious = points; featuresPrevious = features; % Read I(n). % 读取第n张图片。 I = read(buildingScene, n); % Detect and extract SURF features for I(n). %检测和提取surf特征值。 grayImage = rgb2gray(I); points = detectSURFFeatures(grayImage); [features, points] = extractFeatures(grayImage, points); % 匹配I(n)和I(n-1)之间对应的特征点 indexPairs = matchFeatures(features, featuresPrevious, 'Unique', true); matchedPoints = points(indexPairs(:,1), :); matchedPointsPrev = pointsPrevious(indexPairs(:,2), :); % 用MSAC算法计算几何变化。 tforms(n) = estimateGeometricTransform(matchedPoints, matchedPointsPrev,'projective', 'Confidence', 99.9, 'MaxNumTrials', 2000); % 计算T(1) * … * T(n-1) * T(n) tforms(n).T = tforms(n-1).T * tforms(n).T; end imageSize = size(I); % 所有的图像尺寸都是一样的 % 对每个投影变化找到输出的空间坐标限制值。 for i = 1:numel(tforms) [xlim(i,:), ylim(i,:)] = outputLimits(tforms(i), [1 imageSize(2)], [1 imageSize(1)]); end avgXLim = mean(xlim, 2); [~, idx] = sort(avgXLim); centerIdx = floor((numel(tforms)+1)/2); centerImageIdx = idx(centerIdx); Tinv = invert(tforms(centerImageIdx)); for i = 1:numel(tforms) tforms(i).T = Tinv.T * tforms(i).T; end for i = 1:numel(tforms) [xlim(i,:), ylim(i,:)] = outputLimits(tforms(i), [1 imageSize(2)], [1 imageSize(1)]); end % 找到输出空间限制的最大最小值 xMin = min([1; xlim(:)]); xMax = max([imageSize(2); xlim(:)]); yMin = min([1; ylim(:)]); yMax = max([imageSize(1); ylim(:)]); % 全景图的宽高 width = round(xMax - xMin); height = round(yMax - yMin); % 生成空数据的全景图 panorama = zeros([height width 3], 'like', I); blender = vision.AlphaBlender('Operation', 'Binary mask', ... 'MaskSource', 'Input port'); % Create a 2-D spatial reference object defining the size of the panorama. xLimits = [xMin xMax]; yLimits = [yMin yMax]; panoramaView = imref2d([height width], xLimits, yLimits); % Create the panorama. for i = 1:buildingScene.Count I = read(buildingScene, i); % Transform I into the panorama. warpedImage = imwarp(I, tforms(i), 'OutputView', panoramaView); % Overlay the warpedImage onto the panorama. panorama = step(blender, panorama, warpedImage, warpedImage(:,:,1)); end figure imshow(panorama)