[feat](trx-rs): add WFM RDS and playback controls

Co-authored-by: OpenAI Codex <codex@openai.com>
Signed-off-by: Stan Grams <sjg@haxx.space>

src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js

@@ -889,6 +889,9 @@ function render(update) {
   if (update.filter && typeof update.filter.bandwidth_hz === "number") {
     currentBandwidthHz = update.filter.bandwidth_hz;
     syncBandwidthInput(currentBandwidthHz);
+    if (wfmDeemphasisEl && typeof update.filter.wfm_deemphasis_us === "number") {
+      wfmDeemphasisEl.value = String(update.filter.wfm_deemphasis_us);
+    }
   }
   if (update.status && update.status.freq && typeof update.status.freq.hz === "number") {
     lastFreqHz = update.status.freq.hz;
@@ -904,7 +907,7 @@ function render(update) {
   if (update.status && update.status.mode) {
     const mode = normalizeMode(update.status.mode);
     modeEl.value = mode ? mode.toUpperCase() : "";
-    updateWfmAudioModeControl();
+    updateWfmControls();
     // When filter panel is active (SDR backend), update the BW slider range
     // to match the new mode — but only if the server hasn't already sent a
     // filter state that overrides it.
@@ -1475,6 +1478,7 @@ async function applyModeFromPicker() {
     showHint("Mode missing", 1500);
     return;
   }
+  updateWfmControls();
   modeEl.disabled = true;
   showHint("Setting mode…");
   try {
@@ -2052,7 +2056,8 @@ const txAudioBtn = document.getElementById("tx-audio-btn");
 const audioStatus = document.getElementById("audio-status");
 const audioLevelFill = document.getElementById("audio-level-fill");
 const audioRow = document.getElementById("audio-row");
-const wfmAudioModeWrap = document.getElementById("wfm-audio-mode-wrap");
+const wfmControlsCol = document.getElementById("wfm-controls-col");
+const wfmDeemphasisEl = document.getElementById("wfm-deemphasis");
 const wfmAudioModeEl = document.getElementById("wfm-audio-mode");
 
 // Hide audio row if audio is not configured on the server
@@ -2080,6 +2085,8 @@ let txTimeoutTimer = null;
 let txTimeoutRemaining = 0;
 let txTimeoutInterval = null;
 const hasWebCodecs = typeof AudioDecoder !== "undefined" && typeof AudioEncoder !== "undefined";
+const MAX_RX_BUFFER_SECS = 0.25;
+const TARGET_RX_BUFFER_SECS = 0.04;
 
 if (wfmAudioModeEl) {
   wfmAudioModeEl.value = loadSetting("wfmAudioMode", "stereo");
@@ -2087,12 +2094,16 @@ if (wfmAudioModeEl) {
     saveSetting("wfmAudioMode", wfmAudioModeEl.value);
   });
 }
+if (wfmDeemphasisEl) {
+  wfmDeemphasisEl.addEventListener("change", () => {
+    postPath(`/set_wfm_deemphasis?us=${encodeURIComponent(wfmDeemphasisEl.value)}`).catch(() => {});
+  });
+}
 
-function updateWfmAudioModeControl() {
-  if (!wfmAudioModeWrap) return;
+function updateWfmControls() {
+  if (!wfmControlsCol) return;
   const mode = (modeEl && modeEl.value ? modeEl.value : "").toUpperCase();
-  const channels = (streamInfo && streamInfo.channels) || 1;
-  wfmAudioModeWrap.style.display = mode === "WFM" && channels >= 2 ? "" : "none";
+  wfmControlsCol.style.display = mode === "WFM" ? "" : "none";
 }
 
 // Show compatibility warning for non-Chromium browsers
@@ -2148,8 +2159,9 @@ function startRxAudio() {
       // Stream info JSON
       try {
         streamInfo = JSON.parse(evt.data);
-        updateWfmAudioModeControl();
+        updateWfmControls();
         audioCtx = new AudioContext({ sampleRate: streamInfo.sample_rate || 48000 });
+        audioCtx.resume().catch(() => {});
         rxGainNode = audioCtx.createGain();
         rxGainNode.gain.value = rxVolSlider.value / 100;
         rxGainNode.connect(audioCtx.destination);
@@ -2214,6 +2226,9 @@ function startRxAudio() {
             src.buffer = ab;
             src.connect(rxGainNode);
             const now = audioCtx.currentTime;
+            if (nextPlayTime && nextPlayTime - now > MAX_RX_BUFFER_SECS) {
+              nextPlayTime = now + TARGET_RX_BUFFER_SECS;
+            }
             const schedTime = Math.max(now, (nextPlayTime || now));
             src.start(schedTime);
             nextPlayTime = schedTime + ab.duration;
@@ -2249,7 +2264,7 @@ function startRxAudio() {
     if (txActive) { stopTxAudio(); }
     rxActive = false;
     streamInfo = null;
-    updateWfmAudioModeControl();
+    updateWfmControls();
     rxAudioBtn.style.borderColor = "";
     rxAudioBtn.style.color = "";
     audioStatus.textContent = "Off";
@@ -2272,7 +2287,7 @@ function stopRxAudio() {
   streamInfo = null;
   if (audioWs) { audioWs.close(); audioWs = null; }
   if (audioCtx) { audioCtx.close(); audioCtx = null; }
-  updateWfmAudioModeControl();
+  updateWfmControls();
   rxGainNode = null;
   if (opusDecoder) {
     try { opusDecoder.close(); } catch(e) {}

src/trx-client/trx-frontend/trx-frontend-http/assets/web/index.html

@@ -117,6 +117,23 @@
             <button id="jog-up" type="button" class="jog-btn">+</button>
           </div>
         </div>
+        <div class="controls-col controls-col-wfm label-below-col" id="wfm-controls-col" style="display:none;">
+          <div class="inline wfm-controls-inline">
+            <label class="wfm-control">Deemphasis
+              <select id="wfm-deemphasis" class="status-input">
+                <option value="50">50 uS</option>
+                <option value="75">75 uS</option>
+              </select>
+            </label>
+            <label class="wfm-control">Audio
+              <select id="wfm-audio-mode" class="status-input">
+                <option value="stereo">Stereo</option>
+                <option value="mono">Mono</option>
+              </select>
+            </label>
+          </div>
+          <div class="label"><span>WFM</span></div>
+        </div>
         <div class="controls-col controls-col-power label-below-col" id="tx-power-col">
           <div class="label"><span>Transmit / Power</span></div>
           <div class="btn-grid">
@@ -168,7 +185,6 @@
         <button id="tx-audio-btn" type="button">TX Audio</button>
         <label class="vol-label">RX<input type="range" id="rx-vol" min="0" max="100" value="80" class="vol-slider" /><small class="vol-pct" id="rx-vol-pct">80%</small></label>
         <label class="vol-label">TX<input type="range" id="tx-vol" min="0" max="100" value="80" class="vol-slider" /><small class="vol-pct" id="tx-vol-pct">80%</small></label>
-        <label class="vol-label" id="wfm-audio-mode-wrap" style="display:none;">WFM<select id="wfm-audio-mode" class="status-input"><option value="stereo">Stereo</option><option value="mono">Mono</option></select></label>
         <div id="audio-level">
           <div id="audio-level-fill"></div>
         </div>

src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css

@@ -79,7 +79,7 @@ input.status-input, select.status-input { width: 100%; padding: 0.45rem 0.5rem;
 #freq { font-family: 'DSEG14 Classic', monospace; font-size: 2rem; padding: 0.5rem 0.6rem; letter-spacing: 0.05em; text-align: center; }
 .controls-row {
   display: grid;
-  grid-template-columns: 1fr auto 1fr;
+  grid-template-columns: minmax(0, 1fr) auto auto minmax(0, 1fr);
   gap: 1rem;
   align-items: start;
 }
@@ -114,6 +114,26 @@ input.status-input, select.status-input { width: 100%; padding: 0.45rem 0.5rem;
   width: auto;
   align-items: center;
 }
+.controls-col-wfm.label-below-col .label {
+  justify-content: flex-start;
+}
+.wfm-controls-inline {
+  gap: 0.6rem;
+  justify-content: flex-start;
+}
+.wfm-control {
+  display: flex;
+  align-items: center;
+  gap: 0.35rem;
+  color: var(--text-muted);
+  font-size: 0.85rem;
+  white-space: nowrap;
+}
+.wfm-control .status-input {
+  min-width: 4.6rem;
+  width: auto;
+  font-size: 0.9rem;
+}
 .controls-col-center::after {
   content: "";
   display: block;
@@ -583,9 +603,11 @@ button:focus-visible, input:focus-visible, select:focus-visible {
   .header-rig-switch { width: 100%; justify-content: flex-end; }
   .header-rig-switch select { min-width: 6.5rem; }
   .controls-row { grid-template-columns: 1fr auto; }
+  .controls-col-wfm { grid-column: 1 / -1; }
   .controls-col-power { grid-column: 1 / -1; }
   .controls-col.label-below-col .inline,
   .controls-col.label-below-col .btn-grid { margin-top: 0; }
+  .wfm-controls-inline { flex-wrap: wrap; }
   .ft8-controls { flex-wrap: wrap; }
   #ft8-decode-toggle-btn, #wspr-decode-toggle-btn { white-space: nowrap; }
   .jog-container { flex-wrap: wrap; }

src/trx-client/trx-frontend/trx-frontend-http/src/api.rs

@@ -468,6 +468,19 @@ pub async fn set_fir_taps(
     send_command(&rig_tx, RigCommand::SetFirTaps(query.taps)).await
 }
 
+#[derive(serde::Deserialize)]
+pub struct WfmDeemphasisQuery {
+    pub us: u32,
+}
+
+#[post("/set_wfm_deemphasis")]
+pub async fn set_wfm_deemphasis(
+    query: web::Query<WfmDeemphasisQuery>,
+    rig_tx: web::Data<mpsc::Sender<RigRequest>>,
+) -> Result<HttpResponse, Error> {
+    send_command(&rig_tx, RigCommand::SetWfmDeemphasis(query.us)).await
+}
+
 #[post("/toggle_aprs_decode")]
 pub async fn toggle_aprs_decode(
     state: web::Data<watch::Receiver<RigState>>,
@@ -679,6 +692,7 @@ pub fn configure(cfg: &mut web::ServiceConfig) {
         .service(set_tx_limit)
         .service(set_bandwidth)
         .service(set_fir_taps)
+        .service(set_wfm_deemphasis)
         .service(toggle_aprs_decode)
         .service(toggle_cw_decode)
         .service(set_cw_auto)