2026 Migration to Pipewire + BitWig.

2026-06-10 14:16:02 -05:00
parent ee169b0e01
commit a75257a7b0
39 changed files with 256 additions and 1236 deletions
@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+usage() {
+  cat <<'USAGE'
+Usage: ./set-pipewire-latency.sh COMMAND [QUANTUM] [RATE]
+
+Commands:
+  status          Show current PipeWire clock/quantum settings.
+  on [Q] [RATE]   Force a low-latency graph quantum. Defaults: Q=128 RATE=48000.
+  off             Clear forced quantum/rate and return to normal PipeWire behavior.
+
+Useful quantum values at 48 kHz:
+  256  about 5.3 ms per block, safer
+  128  about 2.7 ms per block, good stage starting point
+   64  about 1.3 ms per block, lower latency but higher dropout risk
+USAGE
+}
+
+metadata() {
+  pw-metadata -n settings "$@"
+}
+
+status() {
+  local output
+  output="$(pw-metadata -n settings)"
+  printf '%s\n' "$output" | grep -E "clock\\.(rate|quantum|min-quantum|max-quantum|force-quantum|force-rate)" || true
+
+  local rate quantum forced_quantum
+  rate="$(printf '%s\n' "$output" | awk -F"'" '/clock.rate/ { print $4; exit }')"
+  quantum="$(printf '%s\n' "$output" | awk -F"'" '/clock.quantum/ { print $4; exit }')"
+  forced_quantum="$(printf '%s\n' "$output" | awk -F"'" '/clock.force-quantum/ { print $4; exit }')"
+
+  if [[ -n "$rate" && -n "$quantum" ]]; then
+    awk -v q="$quantum" -v r="$rate" 'BEGIN { printf "\nCurrent block latency: %.2f ms at %s Hz\n", (q / r) * 1000, r }'
+  fi
+
+  if [[ "${forced_quantum:-0}" != "0" ]]; then
+    printf 'Low-latency override: ON\n'
+  else
+    printf 'Low-latency override: OFF\n'
+  fi
+}
+
+set_low_latency() {
+  local quantum="${1:-128}"
+  local rate="${2:-48000}"
+
+  if ! [[ "$quantum" =~ ^[0-9]+$ && "$rate" =~ ^[0-9]+$ ]]; then
+    printf 'Quantum and rate must be numeric.\n' >&2
+    exit 2
+  fi
+
+  metadata 0 clock.force-rate "$rate" >/dev/null
+  metadata 0 clock.force-quantum "$quantum" >/dev/null
+  awk -v q="$quantum" -v r="$rate" 'BEGIN { printf "Forced PipeWire quantum %s at %s Hz, about %.2f ms per block\n", q, r, (q / r) * 1000 }'
+}
+
+clear_low_latency() {
+  metadata 0 clock.force-quantum 0 >/dev/null
+  metadata 0 clock.force-rate 0 >/dev/null
+  printf 'Cleared PipeWire forced quantum/rate.\n'
+}
+
+case "${1:-}" in
+  status)
+    status
+    ;;
+  on)
+    set_low_latency "${2:-128}" "${3:-48000}"
+    ;;
+  off)
+    clear_low_latency
+    ;;
+  -h|--help|help|'')
+    usage
+    ;;
+  *)
+    usage >&2
+    exit 2
+    ;;
+esac