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How do I fix this error?

/ 2024-08-26

deltat=0.1;
nsamples=2^10;
fs=1/deltat;
time=[0 : deltat : deltat*(nsamples-1)];
psdtot(1:nsamples/2+1) = zeros(1,nsamples/2+1);
nblock = 10;
for k=1:nblock
for i=1: nsamples
ydata(i,:) =5+10*cos(2*pi*time+pi/6)+15* randn(1);
end
[pxx,f] = periodogram(ydata,rectwin(nsamples),nsamples,fs);
size(psdtot)
size(pxx)
psdtot = psdtot + pxx/nblock;

end

figure(1);
plot(time,ydata);
I’m trying to generate Gaussian noise from x(t)=5+10*cos(2*pi*t+pi/6)+G(sigma,t)
G(sigma,t) is Gaussian noise with a standard deviation of 15 (sigma G=15), detat=0.1(s), and nsample=2^10.
It is the start of calculating Power Spectral Density with FFT.
The overall variance of the signal is (sigma g)^2+(A)^2/2 as expected.
The generated random signal should be sinusoidal because X(t) has the cosine factor.deltat=0.1;
nsamples=2^10;
fs=1/deltat;
time=[0 : deltat : deltat*(nsamples-1)];
psdtot(1:nsamples/2+1) = zeros(1,nsamples/2+1);
nblock = 10;
for k=1:nblock
for i=1: nsamples
ydata(i,:) =5+10*cos(2*pi*time+pi/6)+15* randn(1);
end
[pxx,f] = periodogram(ydata,rectwin(nsamples),nsamples,fs);
size(psdtot)
size(pxx)
psdtot = psdtot + pxx/nblock;

end

figure(1);
plot(time,ydata);
I’m trying to generate Gaussian noise from x(t)=5+10*cos(2*pi*t+pi/6)+G(sigma,t)
G(sigma,t) is Gaussian noise with a standard deviation of 15 (sigma G=15), detat=0.1(s), and nsample=2^10.
It is the start of calculating Power Spectral Density with FFT.
The overall variance of the signal is (sigma g)^2+(A)^2/2 as expected.
The generated random signal should be sinusoidal because X(t) has the cosine factor. deltat=0.1;
nsamples=2^10;
fs=1/deltat;
time=[0 : deltat : deltat*(nsamples-1)];
psdtot(1:nsamples/2+1) = zeros(1,nsamples/2+1);
nblock = 10;
for k=1:nblock
for i=1: nsamples
ydata(i,:) =5+10*cos(2*pi*time+pi/6)+15* randn(1);
end
[pxx,f] = periodogram(ydata,rectwin(nsamples),nsamples,fs);
size(psdtot)
size(pxx)
psdtot = psdtot + pxx/nblock;

end

Matlab

Thermal Image analysis on legs

/ 2024-08-26

I am trying to edit the below code so that it gives me an image of the area selected that is above the average temperature of the lower limb.
I would be grateful for any tips
clc;
close all;
clear;
workspace;
format long g;
format compact;

% Read the thermal image
thermalImage = imread(‘thermal_image_side_leg_2 .jpeg’); % Replace ‘thermal_image.jpg’ with the filename of your thermal image

% Display the thermal image
figure;
imshow(thermalImage);
title(‘Original Thermal Image’);

% Convert the thermal image to grayscale
thermalImageGray = rgb2gray(thermalImage);

% Display the grayscale thermal image
figure;
imshow(thermalImageGray);
title(‘Grayscale Thermal Image’);

% Select the area of interest using the imfreehand function
figure;
imshow(thermalImageGray);
title(‘Select Area of Interest’);
roi = imfreehand; % This allows you to draw a freehand region of interest (ROI) on the grayscale thermal image
binaryMask = createMask(roi);

% Apply the binary mask to the grayscale image
maskedGrayImage = thermalImageGray .* uint8(binaryMask);

% Display the masked grayscale image
figure;
imshow(maskedGrayImage);
title(‘Masked Grayscale Image’);

% Define the temperature scale using the color bar
colorBarImage = imread(‘Color_bar_side_leg_2.png’); % Replace ‘colorbar_image.jpg’ with the filename of your color bar image
temperatureRange = [26, 38]; % Replace with the temperature range provided by the color bar

% Calibrate the masked grayscale image using the temperature range
calibratedImage = (double(maskedGrayImage) – double(min(thermalImageGray(:)))) * (temperatureRange(2) – temperatureRange(1)) / (double(max(thermalImageGray(:))) – double(min(thermalImageGray(:)))) + temperatureRange(1);

% Display the calibrated image
figure;
imshow(calibratedImage);
title(‘Calibrated Image’);

% Calculate the average temperature of the ROI
averageTemperature = mean(calibratedImage(binaryMask));

% Display the average temperature
disp([‘The average temperature of the selected area is: ‘, num2str(averageTemperature), ‘ °C’]);

% Calculate the average temperature of the ROI
averageTemperature = mean(calibratedImage(binaryMask));

% Display the average temperature
disp([‘The average temperature of the selected area is: ‘, num2str(averageTemperature), ‘ °C’]);

% Threshold the calibrated image to create a binary mask for temperatures above the average
binaryAboveAverage = calibratedImage > averageTemperature;

% Display the binary mask
figure;
imshow(binaryAboveAverage);
title(‘Areas above Average Temperature’);

% Apply the binary mask to the original image
thresholdedImage = thermalImage;
thresholdedImage(repmat(~binaryAboveAverage, [1, 1, 3])) = 0;

% Display the thresholded image
figure;
imshow(thresholdedImage);
title(‘Thresholded Image’);I am trying to edit the below code so that it gives me an image of the area selected that is above the average temperature of the lower limb.
I would be grateful for any tips
clc;
close all;
clear;
workspace;
format long g;
format compact;