Audio Tap.
Records audio from a Firefox tab or from a system monitoring device. Detects start and end from the level and splits the result into separate files. Saves as WAV or MP3 with ID3 tags.
What the extension does
Audio Tap records audio and writes it to the download folder as a WAV or MP3 file.
Two sources
In tab mode the extension taps audio that Firefox plays in the active tab through an audio or video element; no extra software is required.
In loopback mode it records through a monitoring device of the operating system, which also covers programs outside the browser. Such a device has to be set up in the system:
| System | Monitoring device |
|---|---|
| Windows | Virtual audio driver |
| Linux | PulseAudio or PipeWire monitor input |
| macOS | Loopback device |
Automatic splitting
The level is measured continuously. When it rises above an adjustable threshold a recording starts; when it stays below long enough the recording ends. A long session therefore becomes separate files instead of one block full of pauses. A pre-roll buffer keeps the milliseconds before the onset so the beginning is not clipped.
Configurable:
- Threshold at which a recording starts
- Attack and silence times
- Minimum and maximum length of a recording
Automatic segmentation can also be switched off.
Tags and file names
MP3 files can carry title, artist, album, year, genre, comment and track number. The file name can be built from the same fields using a template with placeholders for date, time and a sequential number. Empty fields drop out together with their separators.
What doesn't work
Not every page can be tapped in tab mode. Some playback delivers no signal the extension can read; the level then stays at −100 dB and the built-in diagnostics point this out. Audio generated without an audio or video element is not captured either. Loopback mode covers these cases.
Everything stays local
Recordings stay on the machine. No data is transmitted and no usage data is collected.
The extension asks only for the permissions it needs:
| Permission | What for |
|---|---|
| storage | Settings and the diagnostics display |
| downloads | Writing the finished files to the download folder |
| tabs | Matching the recording to the selected tab, opening the help page |
| <all_urls> | Finding the audio and video elements on arbitrary pages. No page content is read and nothing is sent out. |
Under the hood
- Output as WAV or MP3 with ID3 tags
- MP3 encoding via lamejs 1.2.1 (LGPL-3.0)
- German and English