ebur128_stream/
snapshot.rs

1//! Per-call view of the analyzer's current measurements.
2//!
3//! [`Snapshot`] is cheap to read (`O(1)` for momentary / short-term —
4//! values are cached on each new block; `O(programme blocks)` for
5//! integrated — see [`Snapshot::integrated_lufs`]).
6
7/// A point-in-time view of the analyzer's measurements.
8///
9/// Returned from [`Analyzer::snapshot`].
10///
11/// All accessors return `Option<f64>`:
12/// - `Some(value)` when the requested mode was selected at build time
13///   *and* enough audio has been ingested for that measurement.
14/// - `None` when the mode wasn't selected, or there isn't enough data
15///   yet (for example, less than 400 ms of audio has been pushed for
16///   momentary loudness).
17///
18/// [`Analyzer::snapshot`]: crate::Analyzer::snapshot
19#[derive(Debug, Clone, Copy, Default, PartialEq)]
20#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
21pub struct Snapshot {
22    pub(crate) momentary_lufs: Option<f64>,
23    pub(crate) short_term_lufs: Option<f64>,
24    pub(crate) integrated_lufs: Option<f64>,
25    pub(crate) true_peak_dbtp: Option<f64>,
26    pub(crate) loudness_range_lu: Option<f64>,
27    pub(crate) programme_duration_seconds: f64,
28}
29
30impl Snapshot {
31    /// Momentary loudness (sliding 400 ms window) in LUFS.
32    #[inline]
33    #[must_use]
34    pub fn momentary_lufs(&self) -> Option<f64> {
35        self.momentary_lufs
36    }
37
38    /// Short-term loudness (sliding 3 s window) in LUFS.
39    #[inline]
40    #[must_use]
41    pub fn short_term_lufs(&self) -> Option<f64> {
42        self.short_term_lufs
43    }
44
45    /// Integrated (gated) loudness over the audio pushed so far, in LUFS.
46    ///
47    /// Computing this involves a pass over the programme buffer; the
48    /// analyzer caches the result and invalidates the cache when new
49    /// audio is pushed, so polling at \~10 Hz from a real-time monitor
50    /// is safe.
51    #[inline]
52    #[must_use]
53    pub fn integrated_lufs(&self) -> Option<f64> {
54        self.integrated_lufs
55    }
56
57    /// Maximum true-peak observed so far, in dBTP.
58    #[inline]
59    #[must_use]
60    pub fn true_peak_dbtp(&self) -> Option<f64> {
61        self.true_peak_dbtp
62    }
63
64    /// Loudness range (95 % − 10 % of doubly-gated short-term values), in LU.
65    #[inline]
66    #[must_use]
67    pub fn loudness_range_lu(&self) -> Option<f64> {
68        self.loudness_range_lu
69    }
70
71    /// Total duration of audio ingested, in seconds.
72    #[inline]
73    #[must_use]
74    pub fn programme_duration_seconds(&self) -> f64 {
75        self.programme_duration_seconds
76    }
77}
ebur128_stream/snapshot.rs

ebur128_stream/
snapshot.rs
