fix(sync): tune hdmi av alignment

Cargo.lock

@@ -1642,7 +1642,7 @@ checksum = "09edd9e8b54e49e587e4f6295a7d29c3ea94d469cb40ab8ca70b288248a81db2"
 
 [[package]]
 name = "lesavka_client"
-version = "0.13.1"
+version = "0.13.2"
 dependencies = [
  "anyhow",
  "async-stream",
@@ -1676,7 +1676,7 @@ dependencies = [
 
 [[package]]
 name = "lesavka_common"
-version = "0.13.1"
+version = "0.13.2"
 dependencies = [
  "anyhow",
  "base64",
@@ -1688,7 +1688,7 @@ dependencies = [
 
 [[package]]
 name = "lesavka_server"
-version = "0.13.1"
+version = "0.13.2"
 dependencies = [
  "anyhow",
  "base64",

client/Cargo.toml

@@ -4,7 +4,7 @@ path                    = "src/main.rs"
 
 [package]
 name                    = "lesavka_client"
-version                 = "0.13.1"
+version                 = "0.13.2"
 edition                 = "2024"
 
 [dependencies]

common/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name                    = "lesavka_common"
-version                 = "0.13.1"
+version                 = "0.13.2"
 edition                 = "2024"
 build                   = "build.rs"
 

docs/operational-env.md

@@ -98,6 +98,7 @@ Hardware-facing assumptions belong near the code that uses them; this file is th
 | `LESAVKA_HDMI_CONNECTOR` | server hardware/device override |
 | `LESAVKA_HDMI_DRIVER` | server hardware/device override |
 | `LESAVKA_HDMI_FBDEV` | server hardware/device override |
+| `LESAVKA_HDMI_PRESENTATION_DELAY_US` | server HDMI video latency override |
 | `LESAVKA_HDMI_HEIGHT` | server hardware/device override |
 | `LESAVKA_HDMI_MODES` | server hardware/device override |
 | `LESAVKA_HDMI_RESTORE_CRTC` | server hardware/device override |
@@ -184,7 +185,7 @@ Hardware-facing assumptions belong near the code that uses them; this file is th
 | `LESAVKA_UAC_BUFFER_TIME_US` | server audio sink latency override |
 | `LESAVKA_UAC_COMPENSATION_US` | server audio sink latency override |
 | `LESAVKA_UAC_DEV` | server hardware/device override |
-| `LESAVKA_UAC_HDMI_COMPENSATION_US` | server audio sink latency override |
+| `LESAVKA_UAC_HDMI_COMPENSATION_US` | server HDMI audio sink latency override |
 | `LESAVKA_UAC_LATENCY_TIME_US` | server audio sink latency override |
 | `LESAVKA_TEST_CAM_U32` | test/build contract variable; not runtime operator config |
 | `LESAVKA_TEST_CAP_CAMERA` | test/build contract variable; not runtime operator config |

scripts/ci/quality_gate_baseline.json

@@ -278,7 +278,7 @@
     },
     "server/src/audio/voice_input.rs": {
       "line_percent": 100.0,
-      "loc": 358
+      "loc": 360
     },
     "server/src/bin/lesavka_uvc/control_payloads.rs": {
       "line_percent": 100.0,
@@ -410,7 +410,7 @@
     },
     "server/src/video_sinks/hdmi_sink.rs": {
       "line_percent": 100.0,
-      "loc": 393
+      "loc": 423
     },
     "server/src/video_sinks/webcam_sink.rs": {
       "line_percent": 100.0,

scripts/install/server.sh

@@ -433,8 +433,10 @@ fi
   printf 'LESAVKA_HDMI_SINK=%s\n' "${LESAVKA_HDMI_SINK:-fbdevsink}"
   printf 'LESAVKA_HDMI_FBDEV=%s\n' "${LESAVKA_HDMI_FBDEV:-/dev/fb0}"
   printf 'LESAVKA_HDMI_DRIVER=%s\n' "${LESAVKA_HDMI_DRIVER:-vc4}"
+  printf 'LESAVKA_HDMI_PRESENTATION_DELAY_US=%s\n' "${LESAVKA_HDMI_PRESENTATION_DELAY_US:-180000}"
   printf 'LESAVKA_UAC_DEV=%s\n' "${LESAVKA_UAC_DEV:-hw:UAC2Gadget,0}"
   printf 'LESAVKA_ALSA_DEV=%s\n' "${LESAVKA_ALSA_DEV:-hw:UAC2Gadget,0}"
+  printf 'LESAVKA_UAC_HDMI_COMPENSATION_US=%s\n' "${LESAVKA_UAC_HDMI_COMPENSATION_US:-0}"
 } | sudo tee /etc/lesavka/server.env >/dev/null
 
 echo "==> 6a. Systemd units - lesavka-core"

scripts/manual/run_upstream_av_sync.sh

@@ -21,6 +21,7 @@ LOCAL_OUTPUT_DIR=${LOCAL_OUTPUT_DIR:-"${REPO_ROOT}/tmp"}
 VIDEO_SIZE=${VIDEO_SIZE:-1280x720}
 VIDEO_FPS=${VIDEO_FPS:-30}
 VIDEO_FORMAT=${VIDEO_FORMAT:-mjpeg}
+REMOTE_AUDIO_SOURCE=${REMOTE_AUDIO_SOURCE:-auto}
 SSH_OPTS=${SSH_OPTS:-"-o BatchMode=yes -o ConnectTimeout=5"}
 
 mkdir -p "${LOCAL_OUTPUT_DIR}"
@@ -33,13 +34,15 @@ ssh ${SSH_OPTS} "${TETHYS_HOST}" bash -s -- \
   "${CAPTURE_SECONDS}" \
   "${VIDEO_SIZE}" \
   "${VIDEO_FPS}" \
-  "${VIDEO_FORMAT}" <<'REMOTE_CAPTURE_SCRIPT' &
+  "${VIDEO_FORMAT}" \
+  "${REMOTE_AUDIO_SOURCE}" <<'REMOTE_CAPTURE_SCRIPT' &
 set -euo pipefail
 remote_capture=$1
 capture_seconds=$2
 video_size=$3
 video_fps=$4
 video_format=$5
+remote_audio_source=$6
 
 rm -f "${remote_capture}"
 video_args=(-f video4linux2 -framerate "${video_fps}" -video_size "${video_size}")
@@ -47,17 +50,73 @@ if [[ -n "${video_format}" ]]; then
   video_args+=(-input_format "${video_format}")
 fi
 
-ffmpeg -hide_banner -loglevel error -y \
+resolve_pulse_source() {
-  -thread_queue_size 1024 \
+  if ! command -v pactl >/dev/null 2>&1; then
-  "${video_args[@]}" \
+    return 1
-  -i /dev/video0 \
+  fi
-  -thread_queue_size 1024 \
+  pactl list short sources 2>/dev/null \
-  -f alsa -ac 2 -ar 48000 \
+    | awk '
-  -i hw:3,0 \
+      /alsa_input\..*Lesavka_Composite/ { print $2; found=1; exit }
-  -t "${capture_seconds}" \
+      /Lesavka_Composite/ && !fallback { fallback=$2 }
-  -c:v ffv1 -level 3 -g 1 \
+      END {
-  -c:a pcm_s16le \
+        if (found) exit 0
-  "${remote_capture}"
+        if (fallback != "") { print fallback; exit 0 }
+        exit 1
+      }
+    '
+}
+
+audio_mode="alsa"
+alsa_audio_dev="hw:3,0"
+pulse_source=""
+if [[ "${remote_audio_source}" == "auto" ]]; then
+  if pulse_source="$(resolve_pulse_source)"; then
+    audio_mode="pipewire"
+  else
+    printf 'PipeWire Lesavka source not found; falling back to hw:3,0\n' >&2
+  fi
+elif [[ "${remote_audio_source}" == pulse:* ]]; then
+  audio_mode="pipewire"
+  pulse_source="${remote_audio_source#pulse:}"
+elif [[ "${remote_audio_source}" == alsa:* ]]; then
+  alsa_audio_dev="${remote_audio_source#alsa:}"
+else
+  printf 'unsupported REMOTE_AUDIO_SOURCE=%s\n' "${remote_audio_source}" >&2
+  exit 64
+fi
+
+if [[ "${audio_mode}" == "pipewire" ]]; then
+  printf 'using PipeWire source: %s\n' "${pulse_source}" >&2
+  pw-record --target "${pulse_source}" \
+    --rate 48000 \
+    --channels 2 \
+    --format s16 \
+    --latency 10ms \
+    --raw - | \
+  ffmpeg -hide_banner -loglevel error -y \
+    -thread_queue_size 1024 \
+    "${video_args[@]}" \
+    -i /dev/video0 \
+    -thread_queue_size 1024 \
+    -f s16le -ac 2 -ar 48000 \
+    -i pipe:0 \
+    -t "${capture_seconds}" \
+    -c:v ffv1 -level 3 -g 1 \
+    -c:a pcm_s16le \
+    "${remote_capture}"
+else
+  ffmpeg -hide_banner -loglevel error -y \
+    -thread_queue_size 1024 \
+    "${video_args[@]}" \
+    -i /dev/video0 \
+    -thread_queue_size 1024 \
+    -f alsa -ac 2 -ar 48000 \
+    -i "${alsa_audio_dev}" \
+    -t "${capture_seconds}" \
+    -c:v ffv1 -level 3 -g 1 \
+    -c:a pcm_s16le \
+    "${remote_capture}"
+fi
 REMOTE_CAPTURE_SCRIPT
 capture_pid=$!
 
@@ -87,9 +146,13 @@ if [[ "${probe_status}" -ne 0 ]]; then
   exit "${probe_status}"
 fi
 if [[ "${capture_status}" -ne 0 ]]; then
+  if [[ "${capture_status}" -eq 141 && -f "${LOCAL_CAPTURE}" ]]; then
+    echo "Tethys capture ended with PipeWire SIGPIPE after ffmpeg closed; accepting preserved capture ${LOCAL_CAPTURE}" >&2
+  else
   echo "Tethys capture failed with status ${capture_status}" >&2
   [[ -f "${LOCAL_CAPTURE}" ]] && echo "partial capture preserved at ${LOCAL_CAPTURE}" >&2
   exit "${capture_status}"
+  fi
 fi
 
 echo "==> analyzing capture"

server/Cargo.toml

@@ -10,7 +10,7 @@ bench                   = false
 
 [package]
 name                    = "lesavka_server"
-version                 = "0.13.1"
+version                 = "0.13.2"
 edition                 = "2024"
 autobins                = false
 

server/src/audio/voice_input.rs

@@ -81,7 +81,9 @@ fn voice_sink_compensation_us() -> i64 {
 fn default_voice_sink_compensation_us() -> i64 {
     let cfg = crate::camera::current_camera_config();
     if cfg.output == crate::camera::CameraOutput::Hdmi {
-        non_negative_voice_sink_timing_env("LESAVKA_UAC_HDMI_COMPENSATION_US", 105_000)
+        // HDMI now prefers MJPEG on hosts without hardware H.264 decode, which
+        // removed the old video-side lag that justified the large audio pad.
+        non_negative_voice_sink_timing_env("LESAVKA_UAC_HDMI_COMPENSATION_US", 0)
     } else {
         0
     }
@@ -336,8 +338,8 @@ mod voice_sink_timing_tests {
             temp_env::with_var_unset("LESAVKA_UAC_HDMI_COMPENSATION_US", || {
                 temp_env::with_var("LESAVKA_CAM_OUTPUT", Some("hdmi"), || {
                     update_camera_config();
-                    assert_eq!(default_voice_sink_compensation_us(), 105_000);
+                    assert_eq!(default_voice_sink_compensation_us(), 0);
-                    assert_eq!(voice_sink_compensation_us(), 105_000);
+                    assert_eq!(voice_sink_compensation_us(), 0);
                 });
             });
         });

server/src/tests/runtime_support.rs

@@ -107,10 +107,7 @@ fn preferred_uac_candidates_include_detected_cards_before_alias_fallbacks() {
         ],
         || {
             let candidates = preferred_uac_device_candidates("hw:UAC2Gadget,0");
-            assert_eq!(
+            assert_eq!(candidates.first().map(String::as_str), Some("hw:7,3"));
-                candidates.first().map(String::as_str),
-                Some("hw:7,3")
-            );
             assert!(candidates.iter().any(|value| value == "plughw:7,3"));
             assert!(
                 candidates

server/src/video_sinks/hdmi_sink.rs

@@ -10,6 +10,7 @@ pub struct HdmiSink {
     pipe: gst::Pipeline,
     next_pts_us: AtomicU64,
     frame_step_us: u64,
+    presentation_delay_us: u64,
 }
 
 #[cfg(any(not(coverage), test))]
@@ -17,6 +18,15 @@ fn hdmi_queue_buffers() -> u32 {
     crate::video_support::env_u32("LESAVKA_HDMI_QUEUE_BUFFERS", 1).max(1)
 }
 
+#[cfg(any(not(coverage), test))]
+fn hdmi_presentation_delay_us() -> u64 {
+    // The HDMI + capture-adapter path still lands video earlier than the UAC
+    // path on Tethys-style consumers, even after the stale audio holdback was
+    // removed. Start with a measured default that keeps A/V within one video
+    // frame instead of requiring per-host hand tuning.
+    crate::video_support::env_u32("LESAVKA_HDMI_PRESENTATION_DELAY_US", 180_000) as u64
+}
+
 impl HdmiSink {
     /// Build a new HDMI sink pipeline.
     ///
@@ -49,6 +59,7 @@ impl HdmiSink {
             pipe: pipeline,
             next_pts_us: AtomicU64::new(0),
             frame_step_us,
+            presentation_delay_us: 0,
         })
     }
 
@@ -82,6 +93,7 @@ impl HdmiSink {
             .build()?;
 
         let queue_depth = hdmi_queue_buffers();
+        let presentation_delay_us = hdmi_presentation_delay_us();
         let queue = gst::ElementFactory::make("queue")
             .property("max-size-buffers", queue_depth)
             .property("max-size-bytes", 0u32)
@@ -94,6 +106,7 @@ impl HdmiSink {
         tracing::info!(
             target: "lesavka_server::video",
             queue_depth,
+            presentation_delay_us,
             "📺 HDMI sink queue depth armed"
         );
 
@@ -184,6 +197,7 @@ impl HdmiSink {
             pipe: pipeline,
             next_pts_us: AtomicU64::new(0),
             frame_step_us,
+            presentation_delay_us,
         })
     }
 
@@ -203,8 +217,11 @@ impl HdmiSink {
     pub fn push(&self, pkt: VideoPacket) {
         let mut buf = gst::Buffer::from_slice(pkt.data);
         if let Some(meta) = buf.get_mut() {
-            let pts_us =
+            let pts_us = crate::video_support::reserve_local_pts(
-                crate::video_support::reserve_local_pts(&self.next_pts_us, pkt.pts, self.frame_step_us);
+                &self.next_pts_us,
+                pkt.pts.saturating_add(self.presentation_delay_us),
+                self.frame_step_us,
+            );
             let ts = gst::ClockTime::from_useconds(pts_us);
             meta.set_pts(Some(ts));
             meta.set_dts(Some(ts));
@@ -369,7 +386,7 @@ fn read_bool_env(name: &str) -> Option<bool> {
 
 #[cfg(test)]
 mod hdmi_queue_tests {
-    use super::hdmi_queue_buffers;
+    use super::{hdmi_presentation_delay_us, hdmi_queue_buffers};
 
     #[test]
     fn hdmi_queue_depth_defaults_to_one_frame() {
@@ -390,4 +407,17 @@ mod hdmi_queue_tests {
             assert_eq!(hdmi_queue_buffers(), 1);
         });
     }
+
+    #[test]
+    fn hdmi_presentation_delay_defaults_to_measured_holdback_and_accepts_override() {
+        temp_env::with_var_unset("LESAVKA_HDMI_PRESENTATION_DELAY_US", || {
+            assert_eq!(hdmi_presentation_delay_us(), 180_000);
+        });
+        temp_env::with_var("LESAVKA_HDMI_PRESENTATION_DELAY_US", Some("185000"), || {
+            assert_eq!(hdmi_presentation_delay_us(), 185_000);
+        });
+        temp_env::with_var("LESAVKA_HDMI_PRESENTATION_DELAY_US", Some("nope"), || {
+            assert_eq!(hdmi_presentation_delay_us(), 180_000);
+        });
+    }
 }