def _reverb()

in denoiser/augment.py [0:0]

• 18 lines of code
• 5 McCabe index (conditional complexity)

    def _reverb(self, source, initial, first_delay, rt60):
        """
        Return the reverb for a single source.
        """
        length = source.shape[-1]
        reverb = th.zeros_like(source)
        for _ in range(self.repeat):
            frac = 1  # what fraction of the first echo amplitude is still here
            echo = initial * source
            while frac > 1e-3:
                # First jitter noise for the delay
                jitter = 1 + self.jitter * random.uniform(-1, 1)
                delay = min(
                    1 + int(jitter * first_delay * self.sample_rate),
                    length)
                # Delay the echo in time by padding with zero on the left
                echo = F.pad(echo[:, :, :-delay], (delay, 0))
                reverb += echo

                # Second jitter noise for the attenuation
                jitter = 1 + self.jitter * random.uniform(-1, 1)
                # we want, with `d` the attenuation, d**(rt60 / first_ms) = 1e-3
                # i.e. log10(d) = -3 * first_ms / rt60, so that
                attenuation = 10**(-3 * jitter * first_delay / rt60)
                echo *= attenuation
                frac *= attenuation
        return reverb