Module waveform

Audio waveform peaks per (file, audio stream): computed once on a background thread (decoding the whole stream through an AudioSource), cached in memory and on disk under Settings::cache_dir() (key = hash of path + file size + mtime + stream). PEAKS_PER_SEC buckets of mono (min, max).

Structs

Peaks

State 🔒

WaveformCache

Constants

PEAKS_PER_SEC

Functions

cache_file 🔒

compute_peaks 🔒

Sequentially decode source in 4800-frame blocks into 10 ms mono (min, max) buckets. Stops at the first all-zero block at/after duration (so an unknown duration of 0 stops at the first silent block).

load_or_compute 🔒

Disk cache first; else decode the whole stream (empty Peaks when the stream can’t be opened).

mem_key 🔒

ponytail: 64-bit hash as the map key so the per-frame lookup allocates nothing — collisions are astronomically unlikely.