feat: quality profile selection in desktop settings

Adds a Quality dropdown (Auto / Opus 24k / Opus 6k / Codec2 3.2k /
Codec2 1.2k) to both the connect screen and settings panel. The
selected profile is passed through to the engine which configures
the encoder and decoder accordingly.

The desktop engine recv path now auto-switches the decoder codec
when incoming packets use a different codec than expected, enabling
cross-codec interop between clients on different quality settings.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

desktop/index.html

@@ -26,6 +26,15 @@
           <label>Alias
             <input id="alias" type="text" placeholder="your name" />
           </label>
+          <label>Quality
+            <select id="quality">
+              <option value="auto">Auto</option>
+              <option value="good">Opus 24k</option>
+              <option value="degraded">Opus 6k</option>
+              <option value="codec2-3200">Codec2 3.2k</option>
+              <option value="catastrophic">Codec2 1.2k</option>
+            </select>
+          </label>
           <div class="form-row">
             <label class="checkbox">
               <input id="os-aec" type="checkbox" checked />
@@ -91,6 +100,15 @@
           </div>
           <div class="settings-section">
             <h3>Audio</h3>
+            <label>Quality
+              <select id="s-quality">
+                <option value="auto">Auto (adaptive)</option>
+                <option value="good">Good — Opus 24kbps</option>
+                <option value="degraded">Degraded — Opus 6kbps</option>
+                <option value="codec2-3200">Codec2 3200bps</option>
+                <option value="catastrophic">Catastrophic — Codec2 1200bps</option>
+              </select>
+            </label>
             <label class="checkbox">
               <input id="s-os-aec" type="checkbox" />
               OS Echo Cancellation (macOS VoiceProcessingIO)

desktop/src-tauri/src/engine.rs

@@ -11,9 +11,27 @@ use tracing::{error, info};
 
 use wzp_client::audio_io::{AudioCapture, AudioPlayback};
 use wzp_client::call::{CallConfig, CallEncoder};
-use wzp_proto::MediaTransport;
+use wzp_proto::{CodecId, MediaTransport, QualityProfile};
 
-const FRAME_SAMPLES: usize = 960;
+const FRAME_SAMPLES_20MS: usize = 960;
+const FRAME_SAMPLES_40MS: usize = 1920;
+
+/// Resolve a quality string from the UI to a QualityProfile.
+/// Returns None for "auto" (use default adaptive behavior).
+fn resolve_quality(quality: &str) -> Option<QualityProfile> {
+    match quality {
+        "good" | "opus" => Some(QualityProfile::GOOD),
+        "degraded" | "opus6k" => Some(QualityProfile::DEGRADED),
+        "catastrophic" | "codec2-1200" => Some(QualityProfile::CATASTROPHIC),
+        "codec2-3200" => Some(QualityProfile {
+            codec: CodecId::Codec2_3200,
+            fec_ratio: 0.5,
+            frame_duration_ms: 20,
+            frames_per_block: 5,
+        }),
+        _ => None, // "auto" or unknown
+    }
+}
 
 /// Wrapper to make non-Sync audio handles safe to store in shared state.
 /// The audio handle is only accessed from the thread that created it (drop),
@@ -60,6 +78,7 @@ impl CallEngine {
         room: String,
         alias: String,
         _os_aec: bool,
+        quality: String,
         event_cb: F,
     ) -> Result<Self, anyhow::Error>
     where
@@ -173,21 +192,32 @@ impl CallEngine {
         let send_fs = frames_sent.clone();
         let send_level = audio_level.clone();
         let send_drops = Arc::new(AtomicU64::new(0));
+        let send_quality = quality.clone();
         tokio::spawn(async move {
-            let config = CallConfig {
+            let profile = resolve_quality(&send_quality);
+            let config = match profile {
+                Some(p) => CallConfig {
+                    noise_suppression: false,
+                    suppression_enabled: false,
+                    ..CallConfig::from_profile(p)
+                },
+                None => CallConfig {
                     noise_suppression: false,
                     suppression_enabled: false,
                     ..CallConfig::default()
+                },
             };
+            let frame_samples = (config.profile.frame_duration_ms as usize) * 48;
+            info!(codec = ?config.profile.codec, frame_samples, "send task starting");
             let mut encoder = CallEncoder::new(&config);
             encoder.set_aec_enabled(false); // OS AEC or none
-            let mut buf = vec![0i16; FRAME_SAMPLES];
+            let mut buf = vec![0i16; frame_samples];
 
             loop {
                 if !send_r.load(Ordering::Relaxed) {
                     break;
                 }
-                if capture_ring.available() < FRAME_SAMPLES {
+                if capture_ring.available() < frame_samples {
                     tokio::time::sleep(std::time::Duration::from_millis(5)).await;
                     continue;
                 }
@@ -221,15 +251,17 @@ impl CallEngine {
             }
         });
 
-        // Recv task (direct playout)
+        // Recv task (direct playout with auto codec switch)
         let recv_t = transport.clone();
         let recv_r = running.clone();
         let recv_spk = spk_muted.clone();
         let recv_fr = frames_received.clone();
         tokio::spawn(async move {
-            let mut opus_dec = wzp_codec::create_decoder(wzp_proto::QualityProfile::GOOD);
+            let initial_profile = resolve_quality(&quality).unwrap_or(QualityProfile::GOOD);
+            let mut decoder = wzp_codec::create_decoder(initial_profile);
+            let mut current_codec = initial_profile.codec;
             let mut agc = wzp_codec::AutoGainControl::new();
-            let mut pcm = vec![0i16; FRAME_SAMPLES];
+            let mut pcm = vec![0i16; FRAME_SAMPLES_40MS]; // big enough for any codec
 
             loop {
                 if !recv_r.load(Ordering::Relaxed) {
@@ -242,8 +274,24 @@ impl CallEngine {
                 .await
                 {
                     Ok(Ok(Some(pkt))) => {
-                        if !pkt.header.is_repair {
+                        if !pkt.header.is_repair && pkt.header.codec_id != CodecId::ComfortNoise {
-                            if let Ok(n) = opus_dec.decode(&pkt.payload, &mut pcm) {
+                            // Auto-switch decoder if incoming codec differs
+                            if pkt.header.codec_id != current_codec {
+                                let new_profile = match pkt.header.codec_id {
+                                    CodecId::Opus24k => QualityProfile::GOOD,
+                                    CodecId::Opus6k => QualityProfile::DEGRADED,
+                                    CodecId::Codec2_1200 => QualityProfile::CATASTROPHIC,
+                                    CodecId::Codec2_3200 => QualityProfile {
+                                        codec: CodecId::Codec2_3200,
+                                        fec_ratio: 0.5, frame_duration_ms: 20, frames_per_block: 5,
+                                    },
+                                    other => QualityProfile { codec: other, ..QualityProfile::GOOD },
+                                };
+                                info!(from = ?current_codec, to = ?pkt.header.codec_id, "recv: switching decoder");
+                                let _ = decoder.set_profile(new_profile);
+                                current_codec = pkt.header.codec_id;
+                            }
+                            if let Ok(n) = decoder.decode(&pkt.payload, &mut pcm) {
                                 agc.process_frame(&mut pcm[..n]);
                                 if !recv_spk.load(Ordering::Relaxed) {
                                     playout_ring.write(&pcm[..n]);
@@ -259,7 +307,6 @@ impl CallEngine {
                             error!("recv fatal: {e}");
                             break;
                         }
-                        // Transient error — continue
                     }
                     Err(_) => {}
                 }

desktop/src-tauri/src/main.rs

@@ -122,6 +122,7 @@ async fn connect(
     room: String,
     alias: String,
     os_aec: bool,
+    quality: String,
 ) -> Result<String, String> {
     let mut engine_lock = state.engine.lock().await;
     if engine_lock.is_some() {
@@ -129,7 +130,7 @@ async fn connect(
     }
 
     let app_clone = app.clone();
-    match CallEngine::start(relay, room, alias, os_aec, move |event_kind, message| {
+    match CallEngine::start(relay, room, alias, os_aec, quality, move |event_kind, message| {
         let _ = app_clone.emit(
             "call-event",
             CallEvent {

desktop/src/main.ts

@@ -8,6 +8,7 @@ const callScreen = document.getElementById("call-screen")!;
 const roomInput = document.getElementById("room") as HTMLInputElement;
 const aliasInput = document.getElementById("alias") as HTMLInputElement;
 const osAecCheckbox = document.getElementById("os-aec") as HTMLInputElement;
+const qualitySelect = document.getElementById("quality") as HTMLSelectElement;
 const connectBtn = document.getElementById("connect-btn") as HTMLButtonElement;
 const connectError = document.getElementById("connect-error")!;
 const roomName = document.getElementById("room-name")!;
@@ -48,6 +49,7 @@ const sRoom = document.getElementById("s-room") as HTMLInputElement;
 const sAlias = document.getElementById("s-alias") as HTMLInputElement;
 const sOsAec = document.getElementById("s-os-aec") as HTMLInputElement;
 const sAgc = document.getElementById("s-agc") as HTMLInputElement;
+const sQuality = document.getElementById("s-quality") as HTMLSelectElement;
 const sFingerprint = document.getElementById("s-fingerprint")!;
 const sRecentRooms = document.getElementById("s-recent-rooms")!;
 const sClearRecent = document.getElementById("s-clear-recent")!;
@@ -74,6 +76,7 @@ interface Settings {
   alias: string;
   osAec: boolean;
   agc: boolean;
+  quality: string;
   recentRooms: RecentRoom[];
 }
 
@@ -81,7 +84,7 @@ function loadSettings(): Settings {
   const defaults: Settings = {
     relays: [{ name: "Default", address: "193.180.213.68:4433" }],
     selectedRelay: 0, room: "android", alias: "",
-    osAec: true, agc: true, recentRooms: [],
+    osAec: true, agc: true, quality: "auto", recentRooms: [],
   };
   try {
     const raw = localStorage.getItem("wzp-settings");
@@ -156,6 +159,7 @@ function applySettings() {
   roomInput.value = s.room;
   aliasInput.value = s.alias;
   osAecCheckbox.checked = s.osAec;
+  qualitySelect.value = s.quality || "auto";
   renderRecentRooms(s.recentRooms);
   renderRelayButton();
 }
@@ -376,7 +380,7 @@ async function doConnect() {
   userDisconnected = false;
 
   const s = loadSettings();
-  s.room = roomInput.value; s.alias = aliasInput.value; s.osAec = osAecCheckbox.checked;
+  s.room = roomInput.value; s.alias = aliasInput.value; s.osAec = osAecCheckbox.checked; s.quality = qualitySelect.value;
   const room = roomInput.value.trim();
   if (room) {
     const entry: RecentRoom = { relay: relay.address, room };
@@ -388,6 +392,7 @@ async function doConnect() {
     await invoke("connect", {
       relay: relay.address, room: roomInput.value,
       alias: aliasInput.value, osAec: osAecCheckbox.checked,
+      quality: qualitySelect.value,
     });
     showCallScreen();
   } catch (e: any) {
@@ -529,7 +534,7 @@ listen("call-event", (event: any) => {
 // ── Settings ──
 function openSettings() {
   const s = loadSettings();
-  sRoom.value = s.room; sAlias.value = s.alias; sOsAec.checked = s.osAec;
+  sRoom.value = s.room; sAlias.value = s.alias; sOsAec.checked = s.osAec; sQuality.value = s.quality || "auto";
   sFingerprint.textContent = myFingerprint || "(loading...)";
   renderSettingsRecentRooms(s.recentRooms);
   settingsPanel.classList.remove("hidden");
@@ -564,9 +569,9 @@ settingsPanel.addEventListener("click", (e) => { if (e.target === settingsPanel)
 
 settingsSave.addEventListener("click", () => {
   const s = loadSettings();
-  s.room = sRoom.value; s.alias = sAlias.value; s.osAec = sOsAec.checked;
+  s.room = sRoom.value; s.alias = sAlias.value; s.osAec = sOsAec.checked; s.quality = sQuality.value;
   saveSettingsObj(s);
-  roomInput.value = s.room; aliasInput.value = s.alias; osAecCheckbox.checked = s.osAec;
+  roomInput.value = s.room; aliasInput.value = s.alias; osAecCheckbox.checked = s.osAec; qualitySelect.value = s.quality;
   renderRecentRooms(s.recentRooms);
   closeSettings();
 });