How to Measure Noise

How much noise is present in your media? When establishing a quality control process with user submitted content or processing a large collection of audio this can be an important consideration in delivering audiences with clean audio.

The Dolby.io Analyze API can be used to learn how much noise is present in a given file. The Quick Start to Analyzing Media provides steps to follow to get results for your media.

Sample Response

When inspecting the output for noise data there are a few data points of interest.

JSON

{
  "processed_region": {
    "audio": {
      ...,
      "noise": {
        "level_average": -64.72,
        "snr_average": 41.99
      },
      ...
    }
  }
}

level_average

The level_average gives us the average level of stationary noise measured (in dbFS) across the length of the file.

snr_average

The snr_average gives you the stationary noise measured as a signal to noise ration (in dbFS). Generally, a low SNR is a mark of a healthy level of noise.

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Want to measure noise at scale?

Take a look at the Analyzing and Enhancing Archival Recording Collections blog post looking at noise across a Library of Congress collection.