MATLAB: Find the width of various peaks on an intensity plot

peaks peakwidthSignal Processing Toolbox

Hi,

I am trying to find out a way to figure out how to find the width between two peaks. For example, I would like to know the width between the two peaks in blue and the two peaks in red. Unfortunately, when I use the findpeaks function to find the locations, and then find the difference between the locations, it will give me the width of the adjacent peaks (what is represented as the black distance in this plot).

Any help helps!

Thank you!

Best Answer

You can use findpeaks() in the Signal Processing Toolbox. You might want to make it really sensitive to find all the little peaks and then use them to find whatever distances you dream up.

Related Solutions

MATLAB: Extracting sum of intensity values at various locations with various diameters

See the FAQ: http://matlab.wikia.com/wiki/FAQ#How_do_I_create_a_circle.3F to create a circle mask at each centroid.

You can locate the centroids by using thresholding and regionprops()

binaryImage = grayImage > someThreshold;
props = regionprops(binaryImage, grayImage, 'Centroid', 'BoundingBox', 'MeanIntensity', 'Area');
centroids = [props.Centroid];
xCentroids = centroids(1:2:end);
yCentroids = centroids(2:2:end);
allAreas = [props.Area];
allMeanIntensities = [props.MeanIntensity];
integratedGrayValue = allAreas .* allMeanIntensities

See my Image Segmentation Tutorial for a full demo.

Place a circle at each centroid using the FAQ to create a binary image, then use the code above.

To get the overall background intensity you can use the thresholded image

binaryImage = grayImage > someThreshold.
meanBackgroundIntensity = mean(grayImage(~binaryImage));

If you want a background intensity closer to each spot, then it's more complicated - you'll have to make a binary image mask that is a ring shape around each spot.

MATLAB: To find max peak intensity

The findpeaks function (or the islocalmax function) are what I would use, although the max function is also an option for finding one peak.

Best Answer

Related Solutions

MATLAB: Extracting sum of intensity values at various locations with various diameters

MATLAB: To find max peak intensity

Related Question