Find Peaks in Histogram

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Please use search function on this site or use tag peaks on this site to locate examples like this or this.

The general term for a histogram peak in statistics is "mode," (see for example https://link.springer.com/chapter/10....) so for example if you have two local peaks, that would be called a "bimodal" distribution. In image histograms, it's common to have several strong modes. The main challenge in this type of case is the noise, so you would probably want to smooth the histogram before doing some kind of local maximum detection. I would look at what information you're trying to extract and decide how many modes you "should" have, and apply a blur. Like Avio says, the world is full of find_peak functions from that point. The art here is going to be in figuring out how much blur to use, which will be determined by how much separation you expect between the modes.

You want local maxima.

The histogram is a mat, so you can get the value of each index.

How you choose to do this is up to you. But a sliding window, where you have the previous value, current value and next value. If prev < current > next then you have a peak.

That's a pretty crude approach so perhaps you may want to smooth or normalize you values first.