How to find the wavelength from a given photo?
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I want to find the wave-length of few spectral lines like the picture below
Is it possible since i want to use these kind of pictures to find wave length and use those wavelength for using in formulas.
I don't have any other software other than mathlab like simulink.
3 Comments
Star Strider
on 8 Dec 2017
That’s a nonstandard format (.svg), at least for MATLAB. When I tried to load it with imread, it threw an error.
Image Analyst may have some thoughts...
Answers (1)
Image Analyst
on 8 Dec 2017
You'd have to know what column corresponds to what wavelength. For example, is column 1 defined to be 400 nm and the last column is 700 nm? If so, you can just basically take the column, turn it into a percentage of the way from left to right, then multiply by 300 (=700-400) and add 400.
[rows, columns, numberOfColorChannels] = size(rgbImage);
allColumns = 1 : columns;
wavelength = (700-400) * allColumns / columns + 400;
To get the wavelength at some particular column, say column 250, just do
wavelengthAtCol250 = wavelength(250);
8 Comments
Image Analyst
on 11 Dec 2017
Now, I didn't do that, did I? What I did was
[rows, columns, numberOfColorChannels] = size(rgbImage);
allColumns = 1 : columns;
Why did you change it? You can't put constants on the left hand side because size() is going to try to fill up those spots with the values. Also you misspelled rgbImage.
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