Using OBS Studio

OBS Studio (obsproject.com) is a powerful, free, and open-source software suite for video recording and live streaming. It can combine multiple input video and audio signals and record (or stream) them, and so is very useful for screen and session capture. OBS Studio is available for Windows, Mac, and Linux.

For the broadest compatibility with web browsers, the final recording should be in MP4 format, with an H.264 video codec and an AAC audio codec (OBS Studio records audio in AAC format by default). The best strategy is to record initally in MKV format, then later remux without loss of quality (File → Remux Recordings) to MP4 format.

If OBS somehow crashes during recording, an MP4 file cannot be closed properly and the recording is corrupted and lost. An MKV can be recovered.

1 Setup

These are some of the most important settings (for me on my machine): 

o File → Settings → Output

  Output Mode:  Advanced - Recording

  Recording Settings

    Recording Format:  Matroska Video (.mkv)
    Video Encoder:     NVIDIA NVENC H.264  [hw encoder if available, else x264]
    Audio Encode:      CoreAudio AAC       [CoreAudio if available, else FFmpeg AAC]

  Encoder Settings

    Rate Control:      Variable Bitrate
    Bitrate:           5000 Kbps
    Maximum Bitrate:   6000 Kbps


  Output Mode:  Advanced - Audio

    set Audio Bitrate on each track to 192



o File → Settings → Audio

    Sample Rate:  44.1 kHz
    Channels:     Stereo



o File → Settings → Video

    Base (Canvas) Resolution:    3840×2160
    Output (Scaled) Resolution:  1920×1080
    Downscale Filter:            Lanczos (Sharpened scaling, 36 samples)

    Common FPS Values:  20



o File → Settings → Hotkeys

  Set Ctrl-Shift-F1 in *both* Start Recording and Stop Recording fields
  (so acts as toggle)



o File → Settings → Advanced

  Recording

    File Name Formatting

      %CCYY-%MM-%DD-%hh%mm%ss

2 Making a Screen Recording with Audio


o Add Sources
  - Window Capture (say Firefox)
  - Mic/Aux (select microphone)


o Right-click on Window Capture
  - Resize output (source size)

3 Troubleshooting

4 Tutorials