A music and science lover has revealed that some birds can store and retrieve digital data. Specifically, he converted a PNG sketch of a bird into an audio waveform, then tried to embed it in the song memory of a young starling, ready for later retrieval as an image. Benn Jordan made a video of this feat, sharing it on YouTube, and according to his calculations, the bird-based data transfer system could be capable of around 2 MB/s data speeds.
By your definition nothing can be digital since the world is analog. Even the bits in your CPU are voltages in transistors. As such, every real life signal can be distorted.
The point with digital transfers is that you round it back to either 0 or 1, hoping that no bits are distorted enough to have any loss at all.
Exactly. Digital logic, when implemented in analogue, generally have to have forbidden zones where a signal in that range is considerer invalid. Regardless of implementation, digital is about the discretized logic of the system. That is explicitly the whole point of digital: Minor analogue distortion does not change the information content of the signal unless it is so bad as to flip a bit.
This isn’t true in the general case. In the real world, you can have all kinds of distortions: random noise, time shifts, interference from other signals, etc.
You don’t usually see the effects of these because the protocols are designed with the communication channel characteristics in mind in order to reproduce the original signal.
Using birds is just another communication channel with its own distortion characteristics.
That’s exactly what they said.
Precisely… And digital modulation’s entire purpose is for a digital signal to survive those distortions bit-for-bit perfect. Even if we call the digitally-generated spectrogram digital information, the bird simply did not reproduce it exactly. Whatever time, frequency, and amplitude resolution you apply to the signal, if it’s low enough that the bird reproduced the signal exactly within that discretized scheme, then it simply did not achieve 2 MB/s. I would bet that the Shannon capacity of this bird is simply nowhere near 2 MB/s.
If your argument is that the bandwidth calculation is incorrect, then sure I think that’s fair.
But I don’t think it’s correct to say it’s not a digital channel juts because it doesn’t have optimal bandwidth.
Gozz is correct. You’re misunderstanding the nature of a digital signal. What the author did was convert a digital signal to an analog signal, store that analog signal on a bird, then record that analog signal. Whether it was redigitized after the fact is irrelevant. It is not a digital process end-to-end. This is the same as if I were to download a YouTube video, record that video on a VHS tape, then redigitize that video. Not only would the end result not be a bit for bit match, it wouldn’t be a match at all despite containing some of the same visual information, because it would be the product of a digital-analog-digital conversion.
That’s not really how it works in the real world. Usually you have both bandwidth and noise constraints.
Sure you can send something like a square wave but this isn’t practical for real communication channels. Typically you’re sending many sine waves in parallel with multiple amplitudes and phase offsets to represent a sequence of bits (QAM). Then on top of that you’d encode the original data with both a randomizer (to prevent long runs from looking like nothing) and error correction. So usually the system can handle some level of distortion.
What you’re hoping is that by the time the data reaches the user (really, Layer 3), all the errors have already been handled and you never see any issues.
The bird is just another type of noisy channel with its own distortion characteristics.
The point is that at the physical layer you still have a well defined log likelihood test to produce digital information. That’s why QAM lasted so long even though it is not power efficient - because it has an analytical likelihood function.
This is the boundary between digital and analog communications. Since he did not use a digital modulation scheme, this would be a form of analog comms
You are not addressing my critique of your statement, just piling on a bunch of useless extra knowledge just so that you can feel superior.