Video Noise Filtering in Linux

Audacity is the program that can remove noise. However, you need an audio file (not a video file) to work with. The Kino steps can be accomplished using ffmpeg, but they have been done using Kino here since that is how I perform basic clip editing.

Step 1: Extract audio (easy)

1. This must be done on per-part to avoid extra complexities, so it should always be the first thing you do
2. Open Kino project and export to a WAV using the Audio tab

Step 2: Filter noise (takes some patience)

1. Open audio in Audacity
2. Select a segment of white noise
3. Go to Effect > Noise Removal, select "Get Noise Profile"
4. Select entire track
5. Go to Effect > Noise Removal, adjust the step 2 settings, and click "OK"
6. Export to a new WAV file

Step 3: Add filtered audio back to video

1. Open Kino project
2. Select storyboard item that will get the new audio
3. Go to FX tab
4. Leave "Overwrite" tab active with the full time selected
5. Use Audio Filter "Mix", select audio file
6. Change graph in audio filter so line is at the top (maxed)
7. Change "Audio Transition" to "No change"
8. Click "Render"

That's it. The audio track for the video is now updated with reduced noise.