can any one help me i have placed my queries of the code as qsn mark plz answer the qsns and plz help me to draw the bounding around the ball after plotting centeroid ? the below gives output up to plotting a centroid.

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anji venkat 2014-4-5

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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/124608-can-any-one-help-me-i-have-placed-my-queries-of-the-code-as-qsn-mark-plz-answer-the-qsns-and-plz-hel

评论： anji venkat 2014-4-6

采纳的回答： Image Analyst

green.m

在 MATLAB Online 中打开

if true
  % code
endclc;
clear all;
close all;
%----------------video input--------------------------------------%
vid=uigetfile('.avi','select an video');             % to read file to matlab work space
info=mmfileinfo(vid);                     % to get the multimedia info 
t=info.Duration;                                     % to get the duration of video
vid=mmreader(vid);
numFrames = vid.NumberOfFrames;             %to calculate number of frames 
n=numFrames;
get(vid);
framerate=vid.FrameRate;                           % to calculate frame rate 
for i =1:200                                                  % to read first 200 frames 
  frames = read(vid,i);
  imwrite(frames,strcat([int2str(i) '.tif']));               %y strcat%
end
for i= 1:200
  if(i<50)                                                                    %? Why 50 %
  greenBall1=imread([int2str(i),'.tif']);              % y int2str%
  greenball2=imread([int2str(i+1),'.tif']);
%------------------------------------------------------------------%
%figure;imshow(greenBall1);figure;
r = greenBall1(:, :, 1);
g = greenBall1(:, :, 2);
b = greenBall1(:, :, 3);
justGreen = g - r/2 - b/2;
bw = justGreen > 50;
figure;imagesc(greenBall1);
% figure;
% imagesc(bw);
% colormap(gray);
ball1 = bwareaopen(bw, 30);                      % why %
% figure;
% imagesc(ball1);
s1  = regionprops(ball1, {'centroid','Area'});
if isempty(s1)
error('No ball found!');
else
[~, id] = max([s1.Area]);
hold on, plot(s1(id).Centroid(1),s1(id).Centroid(2),'wp','MarkerSize',10,'MarkerFaceColor','b'), hold off
disp(['Center location is (',num2str(s1(id).Centroid(1),4),', ',num2str(s1(id).Centroid(2),4),')']); %?%
end
%--------------------------------------------------------------------------
%-------------------------------------------------------------------------------------------------------%
r1 = greenball2(:, :, 1);
g1 = greenball2(:, :, 2);
b1 = greenball2(:, :, 3);
justGreen2 = g1 - r1/2 - b1/2;
bw2 = justGreen2 > 50;
% figure;imagesc(greenball2);
% figure;imagesc(bw2);
% colormap(gray);
ball2 = bwareaopen(bw2, 30);
%figure;imagesc(ball2);
s2 = regionprops(ball2, {'centroid','area'});     % how centroid is placed %
if isempty(s2)
error('No ball found!');
else
[~, id] = max([s2.Area]);
hold on, plot(s2(id).Centroid(1),s2(id).Centroid(2),'wp','MarkerSize',10,'MarkerFaceColor','r'), hold off
disp(['Center location is (',num2str(s2(id).Centroid(1),4),', ',num2str(s2(id).Centroid(2),4),')'])
end
differ(i,1)=(s2(id).Centroid(1)-s1(id).Centroid(1)).^2;
differ(i,2)=(s2(id).Centroid(2)-s1(id).Centroid(2)).^2;
%disp(differ);
% figure;
% imshow(differ);
% hline = imdistline(differ,s1(id).Centroid,s2(id).Centroid);
% api = iptgetapi(hline);
distance(i,:)=sqrt(differ(i,1)+differ(i,2));
disp(distance);
velocity(i,:)=(distance(i,:)/framerate);
disp('velocity=');
disp(velocity);
end
end
velocity1=mean(distance)/framerate;
disp(velocity1);_

can any one help me i have placed my queries as qsn mark plz answer the qsns and plz help me to draw the bounding around the ball after plotting centeroid ? the code plotted centeroid and calculated velocity of the ball in a video i just want to place a bounding box around the ball so that we complete our project object detection basing on color ?

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Image Analyst 2014-4-5

Here's some help: http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup, or better yet, just attach your m-file with the paper clip icon.

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采纳的回答

Image Analyst 2014-4-5

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/124608-can-any-one-help-me-i-have-placed-my-queries-of-the-code-as-qsn-mark-plz-answer-the-qsns-and-plz-hel#answer_132299

在 MATLAB Online 中打开

The lines you marked are:

imwrite(frames,strcat([int2str(i) '.tif'])); %?%
ball1 = bwareaopen(bw, 30); %?%
disp(['Center location is (',num2str(s1(id).Centroid(1),4),', ',num2str(s1(id).Centroid(2),4),')']); %?%

The first line writes the array out to a file called 1.tif, 2.tif, 3.tif, etc.

The second line takes a binary image (true/false or 1/0) called bw, and removes all regions that are 30 or smaller in area, and gives that back to you in a new binary image called ball1.

The third line displays a sentence in the command window telling you where the centroid is.

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Image Analyst 2014-4-6

Well that's the art of designing robust algorithms. You have to keep tweaking things until it works. It usually works for your first image and then doesn't for other images, so you keep fine tuning your algorithm until it's as robust as you need it to be for all the images you expect to encounter. I'm glad I could help.

anji venkat 2014-4-6