duty cycle for recordings

[kdarras]

We need a new field in the recordings tables called "duty cycle". It describes how many minutes of sound are recorded per period and it can be expressed as a fraction. For instance, 1/3 means 1 minute of sound is recorded every 3 minutes.
If it is better to store that information in two fields (this is likely), then we can call these duty_cycle_recording and duty_cycle_period.

The duty cycle is relevant only for meta-recordings, as with real recordings, the use of a duty cycle will result in separate files (shown with spectrograms #202 ).

Duty-cycled meta-recordings should be shown with banded bars in the timeline. The band color proportions should correspond to the duty cycle, and the duty cycle be included in the label.

[LiuDilongNJ]

How to show better .

1. Directly display the quarter
   
2. Average 10 equal parts
   

[kdarras]

Good question. I prefer the banded one at the bottom - it emphasizes the periodicity better.

[kdarras]

Needed to add to the instructions:

• duty_cycle_recording (duration of duty-cycled recordings in minutes)
• duty_cycle_period (duration of cycle - recording + pause - in minutes)

Isn't it possible to show banded bars for smaller duty cycles too?

If this is impossible or difficult because I chose the second option above, let's change and use option 1 instead. It is clearer because it does not induce the user to think that the bands are actually located where the recordings are.

[LiuDilongNJ]

There is a bug here, which causes the display to be incorrect.

[kdarras]

Display works now but these fields are not yet visible in the recordings table. By the way, it would make sense to add the recording type (metadata/audio) in there as well.
Note: I had an error when manually setting the date of one recording:

It pops up as soon as I enter "0", even though I am not finished yet with typing. I suppose the date check should happen after shifting the focus to another field.

[kdarras]

After importing the metadata.csv file, I obtained an error:

The CSV contains:
recording_start,duration_s,sampling_rate,name,bit_rate,channel_number,duty_cycle_recording,duty_cycle_period
2020-01-01 00:00:00,600,44100,name1,16,2,1,3
2020-01-01 01:00:00,1200,48000,name2,16,1,1,10

However, importing this CSV worked previously.
Any table action or page reload will produce the same error again after this.

[LiuDilongNJ]

I forgot to determine whether it was audio or metadata, which resulted in the metadata also executing the command to read ID3.

[kdarras]

Working in Docker.

[kdarras]

working online

[kdarras]

completed in #511