Recipe: Making a livecoding screencast with QuickTime and RecordIt


This post shows how to make a livecoding screencast free OSX technologies.

Capturing system audio and screen-recording your live coding performance can be done in multiple ways. Here's a method based on Apple's Quicktime and an audio plugin that is part of a third-party software, Record It.

Note: both of these software components are free. The Record It Audio Device which is a free extension that enables you to capture system sounds on your Mac. It acts as a virtual audio input device and sends the sound from music, videos, and system alerts that you would normally hear through your speakers to the input cha

Recording a screencast: steps

  1. Get the Record It audio plugin PS this is a free audio extension, even if it is part of a paid-for software (RecordItAudioDevice.pkg)
    1. Install it by right-clicking on app and selecting 'Open...' to avoid the permissions issue
  2. On AudioMidi Setup, Create an Aggregate Device to combine multiple audio interfaces
    1. Increase sample rate to 96hz, if necessary
  3. Open Quicktime and set it to record your screen, making sure you get audio from the RecordIt audio plugin
  4. Set your DAW (eg Ableton Live) to output audio to RecordIt
  5. Set your computer to output sound to the Aggregate Device (so that you can also hear what's going on e.g. if you are using headsets)

DONE!

record-it-audio-devices.png

Post-processing tips

Often the audio I get from a Quicktime screencast recording is rather weak.

I found an easy way to fix that by using iMovie, which normally comes with any Mac. Here are the steps:

  1. Open the livecoding screencast in iMovie
  2. Detach Audio (right-click on movie bar to see the options menu)
  3. Adjust the volume in the audio track editor, by dragging the mouse up/down (avoid red zones!)
    1. Additionally, you can try using the top left menu: Music Settings > Equalizer > Music Enhance
  4. Save the new movie: Share > File
    • Resolution: 720p 60
    • Quality: High
    • Compress: Faster

Results: For a 10 mins video, that gives me a .mp4 file of ~250M

Upload to YouTube and off you go ;-)

Cite this blog post:


Michele Pasin. Recipe: Making a livecoding screencast with QuickTime and RecordIt. Blog post on www.michelepasin.org. Published on Aug. 30, 2021.

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