Data Review & Export

Opening the recordings browser

Tap the Recordings button (folder icon) in the top bar. The browser opens as a sheet over the main view. If a stream is running, this icon is deactivated. Stop the stream to access the saved recordings.

The browser shows a list of dated subfolders — one per recording day. Each row shows the folder name (date), the number of WAV files in it, and the name of the most recently written file.

Tap a folder to open it and see its files. Each file row shows:

Display title — derived from the file name timestamp
File created date - derived from the file metadata
File size — formatted for easy comparison
iCloud status — a cloud icon if the file is stored in iCloud and not yet downloaded; a download indicator if it is currently downloading
Colour tag — if one has been assigned (see Colour tags)

Tap on the eye icon to open the Data Review interface.

iCloud files and downloading

Files stored in iCloud Drive but not yet downloaded locally are shown with a cloud icon. Tap the file to trigger a download. A spinning indicator appears while the file downloads. Once available locally, the file can be opened for review.

If you are in the field without network access, iCloud-only files cannot be opened until they are downloaded.

Data Review interface

Data Review is designed to match the live view as closely as possible. The waveform and spectrogram use familiar plot gestures, the same palettes, the prominent grid overlay, and adaptive spectrogram colour scaling.

Waveform — an amplitude envelope for the visible review window. Use it to scan timing and amplitude detail.

Spectrogram — the frequency content of the visible review window. The idle spectrogram is prepared offline at high detail so recorded signals can be inspected carefully without replaying the file.

Swipe with one finger to switch between waveform and spectrogram, just as in live view.

Review window

Use the Window slider to change the visible review width. Set it to Full to inspect the whole recording.

In idle review, use a two-finger horizontal pan on either the waveform or spectrogram to move the selected window through the recording. Single-finger swipes still switch between waveform and spectrogram.

The x-axis follows the visible review window, with the right edge representing the newest point in that window. Changing the Window slider keeps review browsing consistent instead of forcing playback.

Playback

Playback is optional. When you press Play, the plots roll like the live view so timing, colour scaling, and recent-signal behaviour match live streaming.

Use PT (default) or HET playback for listening. In HET mode, adjust the heterodyne frequency to shift ultrasonic content into the audible range during the active playback. The preview HET frequency is remembered and scaled proportionally when opening files with different sample rates.

Use Live to leave Data Review and return to the main live view. Use List to go back to the recordings list.

Trimming

Trim is available from the full-window view. Set the Window slider to Full, tap Trim, adjust the trim handles to keep the desired region, then apply the trim to save the shortened recording.

Note: There is no undo option after applying the trim.

Colour tags

You can assign a colour tag to any recording file for quick visual organisation in the field:

7 colours available: Red, Orange, Yellow, Green, Blue, Purple, Grey
Colour tags are stored as Finder colour labels — they appear on the corresponding files in Finder on macOS when accessed via iCloud Drive

To assign a tag, long-press the file in the recordings list and choose Colour Tag. Tap the same colour to remove it.

Exporting a spectrogram image

Spectrogram PNG export happens from the full-window offline spectrogram inside Data Review.

Set the Window slider to Full, switch to the offline spectrogram, then single-tap the plot. A share button appears at the bottom right and hides after a few seconds or after another tap. Tap it to render the export and open the iOS share sheet. From there you can:

Share via AirDrop, Mail, or Messages
Copy the PNG for pasting on another Apple device
Save to Files, etc

The export is a standard landscape PNG suitable for an A4 landscape layout. It is not a screenshot of the current view. Chirps renders scientific axes, ticks, thin grid lines, a colour legend, the filename, and a Chirps attribution. The exported image uses the currently selected colour palette.

Deleting recordings

To delete a file, long-press the file row in the browser and choose Delete, then confirm. The file is removed from local storage. If the file has been synced to iCloud, it is removed from iCloud as well.

Accessing files outside Chirps

Your recordings are standard WAV files available in the Files app:

App Documents: Files app → On iCloud → Chirps
iCloud Drive: Files app → iCloud Drive → Chirps (or your custom folder)
macOS: Finder → iCloud Drive → Chirps

From there they can be opened in any tool that reads WAV: Audacity, Adobe Audition, Raven Pro, Sonic Visualiser, MATLAB, Python (librosa, scipy), or R.

Markdown notes stored in the same folder can also be opened outside Chirps. This includes the managed session-notes.md file and any additional .md files you add yourself.