diff options
| -rw-r--r-- | scrypted/scrypted-viewport.ts | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/scrypted/scrypted-viewport.ts b/scrypted/scrypted-viewport.ts index 8473c31..a752bc3 100644 --- a/scrypted/scrypted-viewport.ts +++ b/scrypted/scrypted-viewport.ts @@ -651,12 +651,19 @@ class ScryptedViewportProvider extends ScryptedDeviceBase // we're paying ~zero extra on the source side, // - ffmpeg sustains real fps; the takePicture loop never could, // - quality stays high (lanczos + q:v 2 ≈ visually lossless). + // Stream-source choice drives end-to-end latency more than + // anything else. remote-recorder hands us the high-bitrate + // main encoder with a large GOP and the camera's own ~10s + // prebuffer baked in — we'd watch the past, not the present. + // Walk substreams from lowest-latency → highest-latency and + // take the first one that resolves. let stream: any; - try { - stream = await cam.getVideoStream({ destination: "remote-recorder" }); - } catch { - stream = await cam.getVideoStream(); + const destOrder = ["low-resolution", "medium-resolution", "local", "remote", "remote-recorder"]; + for (const destination of destOrder) { + try { stream = await cam.getVideoStream({ destination }); break; } + catch { /* try next */ } } + if (!stream) stream = await cam.getVideoStream(); const ffmpegInputBuf: Buffer = await mediaManager.convertMediaObjectToBuffer( stream, "x-scrypted/x-ffmpeg-input"); let ffmpegInput: any; @@ -696,10 +703,23 @@ class ScryptedViewportProvider extends ScryptedDeviceBase workBuf = Buffer.alloc(0); // reset framer state on each respawn const p = spawn(ffmpegPath, [ "-hide_banner", "-loglevel", "error", - "-fflags", "+genpts+nobuffer", "-flags", "low_delay", + // Latency tuning on the INPUT side: don't buffer, don't + // probe, decode straight through. probesize/analyzeduration + // at the minimum keeps ffmpeg from sitting on the first + // ~5s of source to learn the stream layout. + "-fflags", "+genpts+nobuffer+discardcorrupt", + "-flags", "low_delay", + "-avioflags", "direct", + "-probesize", "32", + "-analyzeduration", "0", ...(ffmpegInput.inputArguments || []), "-an", "-sn", "-vf", `${vf},fps=${fps}`, + // -fps_mode drop: when the decoder is behind, throw the + // late frame on the floor instead of queueing it. Without + // this, ffmpeg's output queue fills up and the displayed + // image lags further and further behind reality. + "-fps_mode", "drop", "-c:v", "mjpeg", "-q:v", "2", "-f", "image2pipe", "-flush_packets", "1", "pipe:1", |