Comparing spectrogram similarity over time I have a data set of spectrograms from moving audio recorders. As the recorders get closer, I expect the spectrograms to become more &quot;similar&quot;. I expect this &quot;similarity&quot; to be a function of distance and frequency.
I would like to create a 3d plot or image that has distance and frequency on the x and y, and &quot;similarity&quot; on z. I am not sure how to define this similarity. Is there a standardized way of comparing similar signals in this way?
For spectrogram similarity, I suggest using a metric from image processing known as SSIM - Structural Similarity Index Metric. It is a quantity between $[0,1]$ which denotes the similarity between two images.
The paper is called Image Quality Assessment: From Error Visibility to Structural Similarity. The MATLAB function ssimval() will give you the metric.