This guide walks you through how to use the iNatSpectro Chrome Extension once it has been installed into Google Chrome.
Overview
This extension enhances the iNaturalist website by automatically adding a waveform and spectrogram visualisation to any observation page that includes an audio recording. It helps identify animal calls (especially frogs, bats, and birds) through visual acoustic analysis.
What to Expect
Once installed:
- On observation pages with an audio clip, a dual visualisation appears directly below the iNaturalist audio player:
- Waveform (top): Volume intensity over time.
- Spectrogram (bottom): Frequency content over time with color-coded loudness.
- Waveform (top): Volume intensity over time.
- This visualisation aids in recognizing patterns, harmonics, and acoustic structure typical of various species.
How to Use It
1. Open an iNaturalist Observation with Audio
- Go to https://www.inaturalist.org.
- Find and open an observation that includes an audio recording.
2. Start Playing the Audio
- The spectrogram will not appear immediately.
- Click the Play button on the iNaturalist audio player.
- The extension will begin generating a live spectrogram as the audio plays.
3. (Optional) Generate a Static View
- Below the spectrogram, you’ll see a button labeled “Generate Static View”.
- Clicking this creates a full-length, static spectrogram of the entire audio clip in one view.
4. (Optional) Choose a Profile
- The extension selects a display profile automatically for recordings identified as:
- Bats
- Frogs
- Birds
- Bats
- If the auto-detection isn’t accurate or you want to switch views, you can manually select a profile using the dropdown or control panel provided.
Interpreting the Spectrogram
- X-axis (left to right): Time.
- Y-axis (bottom to top): Frequency (low to high).
- Color intensity: Volume or loudness (brighter = louder).
Use this to match frequency bands, pulse patterns, or pitch changes that are characteristic of specific species.
Known Limitations
- Works only on observation detail pages with native audio files.
- Will not display until audio playback begins.
- Audio hosted externally (e.g., embedded from another site) may not be supported.
Tips for Best Use
- For long or quiet recordings, use the Static View for full coverage.
- Zoom out in your browser to get a wider view.
- Combine spectrogram data with audible playback for best identification results.
Troubleshooting
| Problem | Solution |
| Spectrogram doesn’t appear | Ensure the audio is playing and wait a few seconds |
| Nothing shows at all | Check if JavaScript is enabled and refresh the page |
| Wrong profile applied | Manually select the appropriate profile from the dropdown |
Feedback and Development
This tool is designed for field naturalists, researchers, and community scientists. Feedback is encouraged to improve its accuracy, speed, and visual quality. Contact the developer or contribute via the GitHub repository if applicable.