Those vacation photos you view with envy on social media typically capture what a city looks like. But with a bit of research and an algorithm, they can also reveal a city’s soundscape.
And that information says a lot about how people perceive a city or neighborhood, according to four data scientists from the research group Good City Life, who put together a set of mesmerizing maps called Chatty Maps. By analyzing tags on thousands of public photos, the researchers mapped out the sound profile of streets in 12 cities, including London, New York, Madrid, Boston, and Washington, D.C. On some streets, marked in green, sounds associated with nature dominate. Streets that are predominantly filled with traffic noise or human chatter are marked in red and blue, respectively.
To reach that level of detail, the researchers sifted through thousands of public Flickr photos, identifying each image’s geolocation and taking note of any sound-related words that the photos were tagged with. (The sound-related words are taken from Freesound, the largest crowdsourced online repository of audio samples.) Using an algorithm, the words were categorized into six categories: transport, nature, human, music, mechanical, and indoor sounds.
The team also mapped the correlation between emotion-related and sound-related tags, finding, for example, that human sounds often evoke joy or surprise, while traffic and mechanical sounds are associated with anger and fear.;