How to do film dosimetry?

Which command is used most often for film dosimetry, with separate RGB channels in MATLAB?

[Walter Roberson]

There is not much, but you might want to look at https://www.mathworks.com/matlabcentral/answers/295196-how-detect-crop-and-straighten-a-particular-shape

Answer 1

[ANKUR MOURYA]

if a is image then to extract red channel use command b=a(:,:,1);

Answer 2

[Yash]

Hi Omid,

To work with separate RGB channels in film dosimerty, the "imread" function is commonly used to read images, and "im2double" is used to convert them to a double precision format for analysis. The RGB channels can be separated using indexing. Here's a basic example:

% Read the image
img = imread('film_image.png');

% Convert to double for processing
img = im2double(img);

% Separate RGB channels
redChannel = img(:,:,1);
greenChannel = img(:,:,2);
blueChannel = img(:,:,3);


% Example processing on each channel
% For demonstration, let's just display histograms of each channel

figure;
subplot(3,1,1);
imhist(redChannel);
title('Red Channel Histogram');

subplot(3,1,2);
imhist(greenChannel);
title('Green Channel Histogram');

subplot(3,1,3);

imhist(blueChannel);

title('Blue Channel Histogram');

For film dosimetry, you might also be interested in functions like imshow for displaying images, and rgb2gray if you need to convert RGB images to grayscale, though typically, analysis is done on individual channels.Relevant Links

Here are some resources that might be useful for further exploration:

1. Image Processing Toolbox: https://www.mathworks.com/help/images/
2. Image Processing and Computer Vision: https://www.mathworks.com/solutions/image-video-processing.html
3. imread: https://www.mathworks.com/help/matlab/ref/imread.html
4. im2double: https://www.mathworks.com/help/matlab/ref/im2double.html

These resources should help you get started with film dosimetry analysis using MATLAB. If you have access to specific scientific articles or textbooks, they might also provide more detailed methodologies tailored to your needs.

Answer 3

[Image Analyst]

You can use imsplit to separate an RGB image into individual component images in one line of code:

% Separate RGB image into individual color channels.
[redChannel, greenChannel, blueChannel]  = imsplit(rgbImage);

For film dosimetry, you will of course need to calibrate your images. For example if you're using x-rays, you can take an image of an aluminum step wedge. This will give you a transform to turn a gray scale into something meaningful and physical such as "layers of aluminum".