Angle recognition of objects in the image

Question

tao wang 2022-3-2

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1661750-angle-recognition-of-objects-in-the-image

评论： tao wang 2022-3-2

Like this picture

I want to calculate the angle of the line represented by the two red arrow strips，I want to calculate the angle of the line represented by the two red arrow strips

I have used the program to get the black-and-white picture. I want to know how to get the angle through the black-and-white picture below

Is there any way to get the desired results after getting such pictures，thanks

(edited by DGM to move comment-as-answer into the question body)

3 个评论
显示 1更早的评论隐藏 1更早的评论

tao wang 2022-3-2

thank you

tao wang 2022-3-2

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

DGM 2022-3-2

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1661750-angle-recognition-of-objects-in-the-image#answer_907830

编辑：DGM 2022-3-2

在 MATLAB Online 中打开

This might be a start. This uses the Hough transform tools from IPT.

A = imread('https://www.mathworks.com/matlabcentral/answers/uploaded_files/911775/image.png');

A = rgb2gray(A);

B = A<128;

% find angle of dominant line

[H,T,R] = hough(B);

P = houghpeaks(H,1,'threshold',ceil(0.3*max(H(:))));

lines = houghlines(B,T,R,P,'FillGap',50,'MinLength',10);

% show line

imshow(B); hold on;

plot([lines.point1(1) lines.point2(1)],[lines.point1(2) lines.point2(2)])

% estimated rotation angle

rotangle = lines.theta

rotangle = -39

This might take some tweaking to work more generally with other images. It might be necessary to get more than the dominant line in the call to houghpeaks() and then try to find some common angle between those. Bear in mind that the angles returned may be complements of each other, so it may be necessary to conditionally complement them in order to compare/winnow/average them.