calculate HPBW of given picture?

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Mohammad Khishe
Mohammad Khishe on 21 Sep 2012
this code calculate HPBW of produce image with matlab( peaks order)
clc; % Clear the command window.
close all; % Close all figures (except those of imtool.)
workspace; % Make sure the workspace panel is showing.
fontSize = 20;
% Create sample data.
H = peaks(90);
H = 11*mat2gray(H) - 13;
% Display it.
subplot(2, 2, 1);
surf(H);
xlabel('Azimuth [deg]', 'FontSize', fontSize);
ylabel('Elevation [deg]', 'FontSize', fontSize);
% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]); % Maximize figure.
set(gcf,'name','Demo by ImageAnalyst','numbertitle','off')
% Threshold the image
binaryImage = H > -3;
% Display it.
subplot(2, 2, 2);
imshow(binaryImage);
axis on;
xlabel('Azimuth [deg]', 'FontSize', fontSize);
ylabel('Elevation [deg]', 'FontSize', fontSize);
measurements = regionprops(binaryImage, 'BoundingBox');
bb = [measurements.BoundingBox]
x1 = bb(1);
x2 = x1 + bb(3);
y1 = bb(2);
y2 = y1 + bb(4);
% Plot box over image.
hold on;
plot([x1 x2 x2 x1 x1], [y1 y1 y2 y2 y1], 'r-', 'LineWidth', 2);
message = sprintf('The Azimuth Width at -3 dB = %.1f\nThe Elevation Width at -3 dB = %.1f', ...
bb(3), bb(4));
msgbox(message);
how can i run it for my image that linked below?
  3 Comments
Mohammad Khishe
Mohammad Khishe on 22 Sep 2012
no half power beam width
Image Analyst
Image Analyst on 23 Sep 2012
And are you now done with this? Because you didn't answer his other question way down at the bottom where he commented on your Answer. Walter and I are basically saying the same thing. You must have data to work with, not some pretty visualization.

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Answers (2)

Image Analyst
Image Analyst on 21 Sep 2012
You can't run it on that picture. You'd need the underlying data that was rendered in that visualization.
  3 Comments
Walter Roberson
Walter Roberson on 21 Sep 2012
Calculate it on your "H" instead.
Image Analyst
Image Analyst on 21 Sep 2012
Edited: Image Analyst on 21 Sep 2012
I have no idea but I know you need it to work on your actual data than some pretty picture of your actual data that was rendered all fancy in some kind of 3D-like chart or perspective picture.

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Mohammad Khishe
Mohammad Khishe on 22 Sep 2012
can you write matlab code that calculate this
  1 Comment
Walter Roberson
Walter Roberson on 22 Sep 2012
Are you starting only from an image, or do you have the data that was used to construct the image?

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