面板刷新率 4Hz -> 62Hz: 服务端加 SSE 推送 /api/stream(FRAME_SEC=16ms), 前端改用 EventSource; 电平表加'上升立刻跟 + 下落每帧最多 0.9dB 平滑 + 峰值保持 1.6 秒', 归一化电平/增益同套平滑, 增益显示两位小数

web/index.html

@@ -226,60 +226,79 @@ const METERS = [
 ];
 const PK = [["pk-inL","in_peak",0],["pk-outL","out_peak",0],["pk-inR","in_peak",1],["pk-outR","out_peak",1]];
 function fmt(db) { return db <= -119 ? "-∞" : db.toFixed(1); }
+/* 表头手感: 上升立刻跟(不丢瞬态), 下落按每帧固定 dB 平滑(不抖),
+   峰值保持 1.6 秒再回落。配上 60 Hz 推送, 数字才是"细腻"而不是乱跳。 */
+const FALL_DB = 0.9;
+const HOLD_SEC = 1.6;
+const disp = {}, pkh = {}, pkt = {};
+function meterSet(id, db) {
+  const prev = disp[id];
+  const cur = (prev === undefined || db >= prev) ? db : Math.max(db, prev - FALL_DB);
+  disp[id] = cur;
+  el("bar-" + id).style.width = Math.max(0, Math.min(100, (cur + 60) / 60 * 100)) + "%";
+  el("val-" + id).textContent = fmt(cur);
+}
+function peakSet(id, db) {
+  const now = Date.now();
+  if (pkh[id] === undefined || db >= pkh[id]) {
+    pkh[id] = db;
+    pkt[id] = now + HOLD_SEC * 1000;
+  } else if (now > (pkt[id] || 0)) {
+    pkh[id] = Math.max(db, pkh[id] - FALL_DB);
+  }
+  el(id).textContent = pkh[id] <= -119 ? "" : fmt(pkh[id]);
+}
 function updateMeters(levels) {
   if (!levels) return;
-  for (const [id, key, ch] of METERS) {
+  for (const [id, key, ch] of METERS) meterSet(id, (levels[key] || [-120, -120])[ch]);
-    const db = (levels[key] || [-120, -120])[ch];
+  for (const [id, key, ch] of PK) peakSet(id, (levels[key] || [-120, -120])[ch]);
-    const pct = Math.max(0, Math.min(100, (db + 60) / 60 * 100));
-    el("bar-" + id).style.width = pct + "%";
-    el("val-" + id).textContent = fmt(db);
-  }
-  for (const [id, key, ch] of PK) {
-    const db = (levels[key] || [-120, -120])[ch];
-    el(id).textContent = db <= -119 ? "" : fmt(db);
-  }
 }
 
 /* ---------- 归一化的电平与动态增益 ---------- */
 function updateLoud(ll) {
   if (!ll) return;
-  const pk = Math.max(ll.peak[0], ll.peak[1]);
+  const pkDb = 20 * Math.log10(Math.max(Math.max(ll.peak[0], ll.peak[1]), 1e-6));
-  const pkDb = 20 * Math.log10(Math.max(pk, 1e-6));
+  const prev = disp["loud"];
-  el("bar-loud").style.width = Math.max(0, Math.min(100, (pkDb + 60) / 60 * 100)) + "%";
+  const cur = (prev === undefined || pkDb >= prev) ? pkDb : Math.max(pkDb, prev - FALL_DB);
-  el("loud-in").textContent = (pkDb <= -119 ? "-∞" : pkDb.toFixed(1)) + " dBFS";
+  disp["loud"] = cur;
+  el("bar-loud").style.width = Math.max(0, Math.min(100, (cur + 60) / 60 * 100)) + "%";
+  el("loud-in").textContent = fmt(cur) + " dBFS";
   const g = (ll.gain_db[0] + ll.gain_db[1]) / 2;      // 两声道共用同一增益
-  el("loud-gain-num").textContent = (g >= 0 ? "+" : "") + g.toFixed(1) + " dB";
+  el("loud-gain-num").textContent = (g >= 0 ? "+" : "") + g.toFixed(2) + " dB";
   // 推子: 量程 -18 ~ +12 dB, 0 dB 落在 60% 处(与刻度线对齐)
   el("loud-gain").style.left = Math.max(0, Math.min(100, (g + 18) / 30 * 100)) + "%";
 }
 
-/* ---------- 轮询 ---------- */
+/* ---------- 实时推送(约 60 Hz) ---------- */
-async function tick() {
+/* DSP 的状态本来就每块更新一次(1024/96000 = 10.7 ms)。原来 250 ms 轮询把表和
-  try {
+   数字拖成了幻灯片, 换成 SSE 推送后按帧渲染。 */
-    const r = await fetch("/api/state");
+const es = new EventSource("/api/stream");
-    const d = await r.json();
+es.onmessage = (ev) => {
-    if (state === null) {
+  try { applyState(JSON.parse(ev.data)); } catch (err) { /* 坏帧忽略 */ }
-      buildEq(d.freqs);
+};
-      gains = d.gains.slice();
+es.onerror = () => say("面板与 DSP 失联, 重连中");
-      eqBox.querySelectorAll("input").forEach((inp) => {
+
-        inp.value = gains[+inp.dataset.index];
+function applyState(d) {
-        const v = inp.previousElementSibling;
+  if (state === null) {
-        const val = parseFloat(inp.value);
+    buildEq(d.freqs);
-        v.textContent = val === 0 ? "" : (val > 0 ? "+" : "") + val.toFixed(1);
+    gains = d.gains.slice();
-      });
+    eqBox.querySelectorAll("input").forEach((inp) => {
-    }
+      inp.value = gains[+inp.dataset.index];
-    if (!isBusy("vol")) { vol.value = d.volume_db; el("vol-num").textContent = (d.volume_db >= 0 ? "+" : "") + d.volume_db.toFixed(1) + " dB"; }
+      const v = inp.previousElementSibling;
-    if (!isBusy("wet")) { wet.value = d.wet; el("wet-num").textContent = (+d.wet).toFixed(2); }
+      const val = parseFloat(inp.value);
-    if (!isBusy("loud") && d.loudness) { loud.value = d.loudness.target_db; el("loud-num").textContent = (+d.loudness.target_db).toFixed(1) + " dB"; }
+      v.textContent = val === 0 ? "" : (val > 0 ? "+" : "") + val.toFixed(1);
-    updateMeters(d.levels);
+    });
-    updateLoud(d.loudness_levels);
+  }
-    state = d;
+  if (!isBusy("vol")) { vol.value = d.volume_db; el("vol-num").textContent = (d.volume_db >= 0 ? "+" : "") + d.volume_db.toFixed(1) + " dB"; }
-  } catch (e) { say("面板与 DSP 失联"); }
+  if (!isBusy("wet")) { wet.value = d.wet; el("wet-num").textContent = (+d.wet).toFixed(2); }
+  if (!isBusy("loud") && d.loudness) { loud.value = d.loudness.target_db; el("loud-num").textContent = (+d.loudness.target_db).toFixed(1) + " dB"; }
+  updateMeters(d.levels);
+  updateLoud(d.loudness_levels);
+  state = d;
 }
 el("flat").addEventListener("click", () => { gains = new Array(32).fill(0); commitEq(); buildEq(state ? state.freqs : []); });
-el("reset").addEventListener("click", () => { state = null; tick(); });
+el("reset").addEventListener("click", () => { state = null; fetch("/api/state").then(r => r.json()).then(applyState).catch(() => say("面板与 DSP 失联")); });
-tick();
+fetch("/api/state").then(r => r.json()).then(applyState).catch(() => say("面板与 DSP 失联"));
-setInterval(tick, 250);
 </script>
 </body>
 </html>

web/server.py

@@ -16,6 +16,7 @@ import json
 import os
 import sys
 import threading
+import time
 from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
 from typing import cast
 
@@ -24,6 +25,7 @@ sys.path.insert(0, os.path.join(os.path.dirname(os.path.abspath(__file__)), os.p
 import common  # noqa: E402
 
 PORT = int(sys.argv[1]) if len(sys.argv) > 1 else 8789
+FRAME_SEC = 0.016                # 面板推送间隔(约 60 Hz)
 UI_PATH = os.path.join(os.path.dirname(os.path.abspath(__file__)), "index.html")
 LOUDNESS_JSON = os.path.expanduser("~/.local/state/cinema-spatial/loudness.json")
 
@@ -88,6 +90,43 @@ class Handler(BaseHTTPRequestHandler):
             return {}
         return cast(dict[str, object], data) if isinstance(data, dict) else {}
 
+    def _snapshot(self) -> dict[str, object]:
+        """面板一帧数据: 参数 + 双声道电平 + 归一化状态 + 响度设置。"""
+        with self.lock:
+            gains, volume_db, wet, _version = common.read_params(self.store)
+            levels = common.read_state(self.store)
+        return {
+            "freqs": common.EQ_FREQS,
+            "loudness_levels": common.read_loudness_state(),
+            "gains": gains,
+            "volume_db": volume_db,
+            "wet": wet,
+            "gain_limit": common.GAIN_LIMIT,
+            "volume_limit": common.VOLUME_LIMIT,
+            "levels": levels,
+            "loudness": read_loudness(),
+        }
+
+    def _stream(self) -> None:
+        """SSE 推送, 约 60 Hz。
+
+        DSP 的状态本来就每块更新一次(1024/96000 = 10.7 ms), 原来卡在面板 250 ms
+        轮询上, 电平表看着很跳。改成推送后前端能跟到帧率, 数字和条都细腻起来。
+        """
+        self.send_response(200)
+        self.send_header("Content-Type", "text/event-stream; charset=utf-8")
+        self.send_header("Cache-Control", "no-cache")
+        self.send_header("Connection", "keep-alive")
+        self.end_headers()
+        try:
+            while True:
+                body = json.dumps(self._snapshot(), ensure_ascii=False)
+                self.wfile.write(("data: %s\n\n" % body).encode("utf-8"))
+                self.wfile.flush()
+                time.sleep(FRAME_SEC)
+        except (BrokenPipeError, ConnectionResetError, OSError):
+            return
+
     def do_GET(self) -> None:
         if self.path in ("/", "/index.html"):
             try:
@@ -103,20 +142,10 @@ class Handler(BaseHTTPRequestHandler):
             self.wfile.write(body)
             return
         if self.path == "/api/state":
-            with self.lock:
+            self._send_json(self._snapshot())
-                gains, volume_db, wet, _version = common.read_params(self.store)
+            return
-                levels = common.read_state(self.store)
+        if self.path == "/api/stream":
-            self._send_json({
+            self._stream()
-                "freqs": common.EQ_FREQS,
-                "loudness_levels": common.read_loudness_state(),
-                "gains": gains,
-                "volume_db": volume_db,
-                "wet": wet,
-                "gain_limit": common.GAIN_LIMIT,
-                "volume_limit": common.VOLUME_LIMIT,
-                "levels": levels,
-                "loudness": read_loudness(),
-            })
             return
         self.send_error(404)