Comment on Yes, you can store data on a bird — enthusiast converts PNG to bird-shaped waveform, teaches young starling to recall file at up to 2MB/s

• gozz@lemmy.world ⁨2⁩ ⁨days⁩ ago

  The whole sequence is:

  • Digitally synthesized spectrogram (lossless)
  • Played through a DAC and speaker to produce an analogue signal (lossy)
  • Heard by the bird (analogue, lossy)
  • Reproduced by the bird (analogue, lossy)
  • Captured by an ADC as a digital audio signal (lossy)
  • Spectrum-analysed to observe a similar (but corrupted) reproduction of the shape in the PNG

  To be transferring digital information, we would instead need to modulate and demodulate the digital signal (exactly like an old modem) so that the analogue corruption does not affect the digital signal:

  • Image file (lossless)
  • Bit stream (lossless)
  • Analogue modulation of bit stream played through DAC (lossy)
  • Heard by the bird (lossy)
  • Reproduced by the bird (lossy)
  • Demodulated to recover exact bit stream despite distortion (lossless,)
  • Decode bit stream to recover original image file, bit-for-bit perfect

  I extremely doubt that this bird is capable of 2MB/s. For reference that would make it 280+ times fast than dialup, and barely slower than ADSL. This setup is basically just using the bird instead of a telephone line.

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  • CookieOfFortune@lemmy.world ⁨2⁩ ⁨days⁩ ago

    • Played through a DAC and speaker to produce an analogue signal (lossy)

    Analogue modulation of bit stream played through DAC (lossy)

    These steps are literally the same thing. You’re converting some data into sound for the bird to hear.

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    • gozz@lemmy.world ⁨2⁩ ⁨days⁩ ago

      Yes, the near-identical sentences (only drawing a distinction between the processes where one exists) would indicate that. The “heard by the bird” and “reproduced by the bird” steps were also the same. But this is necessary context to make clear the digital data (“bit-stream”) that is being modulated into the signal.

      It is far from “exactly the same”. The similarity is only in that both go through the same analogue channel. The entire point is that the modulated signal can be reconstructed exactly, while the spectrogram cannot.

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      • CookieOfFortune@lemmy.world ⁨2⁩ ⁨days⁩ ago

        The entire point is that the modulated signal can be reconstructed exactly,

        But this isn’t true. Just because a signal is modulated doesn’t mean it can’t be distorted.

        A spectrogram is just showing that arbitrary data can be sent though this channel. It’s literally a form of modulation.

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• Underwaterbob@sh.itjust.works ⁨3⁩ ⁨days⁩ ago

  The sound from the speakers he must have used was also “analog”. Sound - defined as a pressure wave through a medium - can’t be digital. Though the difference between analog and digital kinda loses meaning in cases like this.

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  • CookieOfFortune@lemmy.world ⁨3⁩ ⁨days⁩ ago

    Every signal is ultimately analog. Voltage along a wire, sound, light, the world is analog and it all needs to be converted into our concept of digital (which is typically binary values).

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