2022-05-12
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#vanilla javascript
Iskander Samatov
106930
May 12, 2022 ⋅ 10 min read

Write an audio visualizer from scratch with vanilla JavaScript

Iskander Samatov I’m a technical lead at HubSpot based in Dallas-Fort Worth Metropolitan Area. When I have time, I enjoy working on SaaS products and writing programming articles at https://isamatov.com.

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One Reply to "Write an audio visualizer from scratch with vanilla JavaScript"

  1. This was super helpful, but I noticed a slight error in the sample code under “Resizing the Bars” — the second loop requires some adjustments to actually render that half of the visualizer on page.

    I was able to get it working by:
    1. Resetting the value of x in between the two loops.
    2. Setting the X argument of the call to fillRect in the second loop to canvas.width / 2 + x.

    I see a different approach was taken as I examine the code further on in “Tuning the Performance”, which leverages two separate X values, but the result is the same.

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