Question

我试图将alpha混音引入MATLAB panoramic stitching example。该算法成功地融合，但是当使用示例＆＃34; tforms＆＃34;时，拼接的图像被翻译。转换矩阵。

Alpha混合代码在这里：

%% merge images using Alpha blending
%  input:   imgs - source images
%           mask - image mask
%           transforms - transformation matrices to transform each images
%                        into the new coordinate system
%           newHeight, newWidth - size of the new coordinate system
%  output:  newImg - merged image
function [ newImg ] = alphaBlend( imgs, mask, transforms, newHeight, newWidth )
% image information
height = size(imgs, 1);
width = size(imgs, 2);
nChannels = size(imgs, 3);
nImgs = size(imgs, 4);
% alpha mask
mask = imcomplement(mask);
mask(1, :) = 1;
mask(end, :) = 1;
mask(:, 1) = 1;
mask(:, end) = 1;
mask = bwdist(mask, 'euclidean');
mask = mask ./ max(max(mask));
% backward transformation
backTransforms = zeros(size(transforms));
for i = 1 : nImgs
    backTransforms(:, :, i) = inv(transforms(:, :, i));
end
% image merging
newImg = zeros([newHeight newWidth nChannels], 'uint8');
for y = 1 : newHeight
    for x = 1 : newWidth
%         p1 = [y; x; 1];
        p1 = [x; y; 1];
        pixelSum = zeros(nChannels, 1);
        alphaSum = 0;
        for k = 1 : nImgs
%             p2 = backTransforms(:, :, k) * p1;
            p2 = p1' * backTransforms(:,:,k);
            p2 = p2 ./ p2(3);
            xx = p2(1);
            yy = p2(2);
            p2 = [yy; xx; 1];
            if p2(1) >= 1 && p2(1) < height && p2(2) >= 1 && p2(2) < width
                i = floor(p2(2));
                a = p2(2) - i;
                j = floor(p2(1));
                b = p2(1) - j;
                pixel = (1 - a) * (1 - b) * imgs(j, i, :, k)...
                    + a * (1 - b) * imgs(j, i + 1, :, k)...
                    + a * b * imgs(j + 1, i + 1, :, k)...
                    + (1 - a) * b * imgs(j + 1, i, :, k);
                alpha = (1 - a) * (1 - b) * mask(j, i)...
                    + a * (1 - b) * mask(j, i + 1)...
                    + a * b * mask(j + 1, i + 1)...
                    + (1 - a) * b * mask(j + 1, i);
                pixelSum = pixelSum + double(squeeze(pixel)) * double(alpha);
                alphaSum = alphaSum + double(alpha);
            end
        end
        newImg(y, x, :) = pixelSum / alphaSum;
    end
end
end

在全景拼接示例之后，step 4形成了矩阵形式，我尝试以这种方式翻译图像：

mask = ones(imageSize(1),imageSize(2));
% Create the panorama.
% Alpha blending
horiz = 200;
verti = 100;
Translate = [1, 0, 0; 0, 1, 0; horiz, verti, 1];
transforms = Translate * tforms(1).T;
for i =1:numel(tforms) transforms(:,:,i) = Translate * tforms(i).T; end
 panorama1 = alphaBlend( temp, mask, transforms, height, width );

但是，结果图像重叠是关闭的。如何翻译tforms矩阵，以便翻译拼接的全景图像？

翻译Alpha混合的转换矩阵

0 个答案: