MATLAB: Horizontal and vertical projection of an image

horizontal and vertical projection of an imageMATLAB

Hi guys I want to project a binary black n white image in horizontal n vertical direction n den concatenate them plz help me with the matlab code.

Best Answer

The question is not clear. Perhaps this helps:

img = rand(100, 100) < 0.1;
h_projection = any(img, 2);
v_projection = any(img, 1);
cat_projection = cat(1, h_projection, v_projection(:));

Using SUM instead of ANY might be an option also.

Related Solutions

MATLAB: How to find diagonal projection of an handwritten character image (binary matrix)

M =[1 2 3 4; 5 6 7 8; 9 0 1 2; 3 4 5 6]
LD = sum(spdiags(M(end:-1:1,:),1-size(M,1):size(M,2)-1))
RD = sum(spdiags(M',1-size(M,2):size(M,1)-1))

variant 2 without spdiags

M =[1 2 3 4; 5 6 7 8; 9 0 1 2; 3 4 5 6]
[m n] = size(M);
Mi = cumsum([1:n*2-1;(m-1)*ones(m-1,n*2-1)]);
LM = triu(true(size(Mi)));
LM = LM&LM(end:-1:1,end:-1:1);
M1 = M(Mi);
LD = sum(M1.*LM);
M2 = M(:,end:-1:1);
M2 = M2(Mi);
RD = sum(M2.*LM);

variant 3 with bsxfun

m = size(M,1);
idx = bsxfun(@plus,[1:m-1, m:m:numel(M)],(0:m-1:(m-1)^2)');
L = triu(true(size(idx)));
L1 = L&L(:,end:-1:1);
idx(~L1) = 1;
LD = sum(M(idx).*L1);
M1 = M(:,end:-1:1);
RD = sum(M1(idx).*L1);

variant 4 with convmtx from Signal Processing Toolbox

[m n]= size(M);
L = logical(convmtx(ones(n,1),m));
idx = ones(size(L));
idx(L) = 1:m*n;
LD = sum((M(idx).*L)');
M1 = M(:,end:-1:1);
RD = sum((M1(idx).*L)');

MATLAB: Overlay a image with plot

Below are some suggestions: (only for the above code)

(line 14 - 17) Instead of using subplots use figure and save the plot
(line 20, 21) Rotate the image first and then resize it

Below is the code after making changes:

I = imread('Bild_1.jpg');
I=I(:,:,1);
white = sum(I,2);
[Rows,numCols] = size(I);
x0=0;
y0=0;
width=numCols;
height=Rows;
figure
set(gcf,'position',[x0,y0,width,height])
plot(white);
view([90 90]);
saveas(gcf,'Plot_01.png',[x0,y0,width,height]);
P1=imread('Plot_01.png');
P1 = imrotate(P1,90);
P2 = imresize(P1,[Rows,numCols],'bicubic');
figure
imshowpair(P2,I,'blend','Scaling','joint')

Best Answer

Related Solutions

MATLAB: How to find diagonal projection of an handwritten character image (binary matrix)

MATLAB: Overlay a image with plot

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