Review recordings

Recording files on the SD card can be reviewed on the device directly. It is possible to playback a recording and analyse it with the help of spectrograms and metadata. Files and folders can be sorted, filtered, deleted.

File browser

_images/file_explorer.png

To select and open a recording, a file browser lists all the folders and recordings available on the SD card in a hierarchical manner.

Use the _images/unfold-more-horizontal.png keys to select a folder or recording. Press the _images/ok.png key to open the selected item.

Press the _images/back.png key to go back to the parent folder.

Use the _images/f1.png key to:

Filter: Filter recordings by date/time.

Sort: Choose a sorting method of “Name ascending”, “Name descending”, “Date ascending”, “Date descending”, “Size ascending” and “Size descending”

Use the _images/f2.png key to:

Play: Playback the selected recording.

Play all: Playback all recordings in the folder.

Delete: Delete the selected recording or folder.

Recording file

_images/file_metadata.png

In the top part of the screen, the recordings main data is presented:

  • File name and path

  • Timestamp

  • Playback status and progress

  • Length

The recording data is presented in various screens. Use the _images/unfold-more-vertical.png keys to switch screens.

Press the _images/back.png key to go back to the file browser.

Press the _images/f1.png key to:

Delete the current recording.

Press the _images/f2.png key to:

Playback the current recording. Use the Playback screen to change playback parameters.

Recording review screens

Various screens with detailed data of the recording file can be displayed. Use the _images/unfold-more-vertical.png keys to switch screens.

Metadata screen

_images/file_metadata.png

Lists metadata stored with each recording:

  • Trigger frequency

  • Temperature

  • Profile

Use the _images/unfold-more-horizontal.png keys to open the previous or next recording.

Multi-Call spectrogram screen

_images/file_multicall.png

A spectrogram of stitched bat calls is rendered. The “nicest call” with preceding and subsequent calls are displayed, if available.

The y-axis tick marks indicate 20kHz frequency steps. The first x-axis tick mark indicates the cutouts length in ms. Average call parameters (peak frequency ƒ: 45kHz, call length ⏱: 11 ms, call distance ↦: 85 ms) are displayed.

Use the _images/unfold-more-horizontal.png keys to open the previous or next recording. Press the _images/ok.png key to show the frequency guides.

Calls screen

_images/file_calls.png

A list of detected calls is displayed. Only the first 20 calls are listed, even if the recording contains more. For each call, a few call parameters are specified.

Use the _images/unfold-more-horizontal.png keys to select a call. Press the _images/ok.png key to show the spectrogram of this call.

Spectrogram screen

_images/file_spectrogram.png

Displays a short part of the recording as spectrogram. After opening a recording, the “nicest call” is displayed. The y-axis tick marks indicate 20kHz frequency steps. Average call parameters (peak frequency ƒ: 45kHz, call length ⏱: 11 ms) are displayed. Species classification is displayed on availability.

Use the _images/unfold-more-horizontal.png keys to display the previous or next call from the calls list. Press the _images/ok.png key to switch to scroll mode. In scroll mode use the _images/unfold-more-vertical.png keys to scroll the spectrogram to the left or right or the _images/unfold-more-horizontal.png keys to switch display mode (spectrogram, frequency guides, call shape). Press the _images/ok.png key again to leave scroll mode.

Spectrum screen

_images/file_spectrum.png

A graph with the spectrum is displayed. The spectrum data is averaged over the whole recording. The peak frequency is displayed.

Use the _images/unfold-more-horizontal.png keys to open the previous or next recording. Press the _images/ok.png key to switch to cursor mode and display the frequency cursor. Then ue the _images/unfold-more-vertical.png keys to move it an display its frequency. Press the _images/ok.png key again to leave cursor mode.

Tags screen

_images/file_tags.png

A list of the tags is displayed.

Use the _images/unfold-more-horizontal.png keys to select a tag. Press the _images/ok.png key to edit or delete a tag. Select “Add tag…” and press the _images/ok.png key to add a new tag to the recording.

Playback screen

_images/file_playback.png

Switch playback methods and parameters.

Method Pitch

The playback is slowed down by the pitch factor to make ultrasonic audible.

Pitch:

Shows the pitch factor (10).

Method Heterodyne (Mixer)

Use heterodyne transformation to make ultrasonic audible.

Mode:
Automatic: Heterodyne frequency is automatically set to trigger frequency of the recording.
Manual: Use a custom heterodyne frequency (see below).
Cur. Frequency:
In automatic mode: Displays the current heterodyne frequency (trigger frequency). Press _images/ok.png to enter a custom heterodyne frequency and switch to manual mode.
In manual mode: Press _images/ok.png to change custom heterodyne frequency.

Method Divider

The playback signal frequencies are divided by a divider value to make ultrasonic audible.

Divider:

Press _images/ok.png to enter a divider value 4..20.