sva-samples 0.8.1

Buffers, frames, the f64 machine, the collapse of a law onto a grid, and the measured observations over one
Documentation 
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// Concern: the named tolerance set every label cites, and the ceiling and floor it puts on a rate | Non-concern: what a collapse does with either (collapse/), choosing the rate | IO: none -> Profile

use sva_formula::{ContentHasher, HashDomain};

#[derive(Clone, Copy, Debug, PartialEq)]
pub struct Profile {
    pub name: &'static str,
    pub floor_db: f64,
    pub floor_db_above_5k: f64,
    pub ceiling_hz: f64,
    pub precision_bits: i32,
    pub silence_threshold_dbfs: f64,
}

pub const PSYCHOACOUSTIC_V1: Profile = Profile {
    name: "psychoacoustic-v1",
    floor_db: -20.0,
    floor_db_above_5k: -25.0,
    ceiling_hz: 20_000.0,
    precision_bits: 24,
    silence_threshold_dbfs: -120.0,
};

impl Profile {
    pub fn ceiling(&self, rate: u32) -> f64 {
        self.ceiling_hz.min(f64::from(rate) / 2.0)
    }

    pub fn half_lsb(&self) -> f64 {
        2f64.powi(-self.precision_bits)
    }

    pub fn silence_threshold_amplitude(&self) -> f64 {
        10f64.powf(self.silence_threshold_dbfs / 20.0)
    }

    /// Every setting a value or its label depends on.
    pub fn deciding(&self) -> [u64; 6] {
        let Profile {
            name,
            floor_db,
            floor_db_above_5k,
            ceiling_hz,
            precision_bits,
            silence_threshold_dbfs: _,
        } = *self;
        let mut named = ContentHasher::new(HashDomain::ProfileName);
        named.text(name);
        let named = named.finish();
        [
            named.0,
            named.1,
            floor_db.to_bits(),
            floor_db_above_5k.to_bits(),
            ceiling_hz.to_bits(),
            precision_bits as u64,
        ]
    }

    pub fn floor(&self, hz: f64) -> f64 {
        if hz > 5_000.0 {
            self.floor_db_above_5k
        } else {
            self.floor_db
        }
    }
}