fix(video): drop master playlist, advertise media.m3u8 directly to AVPlayer

Verified via standalone aetherctl on macOS QuickTime (which uses the
same AVFoundation HLS pipeline as tvOS AVPlayer):

* With our previous master.m3u8 (`#EXTM3U / #EXT-X-VERSION:7 /
  #EXT-X-INDEPENDENT-SEGMENTS / #EXT-X-STREAM-INF:BANDWIDTH=…,
  CODECS="dvh1",RESOLUTION=3840x2076,VIDEO-RANGE=PQ / media.m3u8`),
  AVPlayer fetches the master once or twice, then drops the session
  without ever attempting `media.m3u8`. No errorLog, no
  failedToPlayToEndTime, no item.status=failed. Just AVPlayer parking
  in `waitingToPlay`. Tried the full RFC 6381 form `dvh1.08.06`,
  same outcome.

* Pointing AVPlayer at `media.m3u8` directly (skipping the master
  entirely) the engine immediately starts serving init.mp4, seg0,
  seg1, … and AVPlayer buffers smoothly through the playlist.

The audio path has always worked this way (no master, the buffered
provider returns nil for `masterCodecs` and `HLSLocalServer.playlist
URL` advertises `media.m3u8`). Adopt the same architecture for video.

Trade-off: lose the explicit `VIDEO-RANGE=PQ` / `CODECS=dvh1.08.LL`
signaling on the variant level. AVPlayer must infer Dolby Vision from
the init segment's `dvh1` sample-entry FourCC, the `dvvC`
configuration box, and the `colr` atom's BT.2020+PQ primaries /
transfer / matrix. Apple's HLS authoring guidance for DV recommends
master-level signaling but doesn't require it for single-variant
streams; segment-level signaling alone is enough for AVPlayer to
recognise the bitstream as DV. Whether the HDMI Dolby Vision
handshake on a capable TV engages with no master playlist is the
follow-up empirical check on the next build.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: superuser404notfound

Sources/AetherEngine/Video/HLSVideoEngine.swift

@@ -645,11 +645,31 @@ private final class VideoSegmentProvider: HLSSegmentProvider {
     }
 
     var playlistType: HLSPlaylistType { .vod }
-    var masterCodecs: String? { codecsString }
-    var masterResolution: (width: Int, height: Int)? {
-        return (resolution.0, resolution.1)
-    }
-    var masterVideoRange: HLSVideoRange? { videoRange }
+    // Returning nil here suppresses the master playlist entirely, so
+    // `HLSLocalServer.playlistURL` advertises `media.m3u8` directly
+    // and the `/master.m3u8` endpoint 404s. The audio path has always
+    // worked this way; the video path was generating a single-variant
+    // master with `CODECS="dvh1"` + `VIDEO-RANGE=PQ` + `RESOLUTION=
+    // 3840x2076`, and AVPlayer (verified on both macOS QuickTime and
+    // tvOS) silently parse-rejects that master, fetches it 2-3 times,
+    // then drops the session without ever attempting `media.m3u8`.
+    // No `errorLog`, no `failedToPlayToEndTime`, just AVPlayer parking
+    // in `waitingToPlay` forever. macOS QuickTime fed `media.m3u8`
+    // directly happily reads init.mp4, seg0..segN, and starts buffer
+    // ing; that's the architecture we adopt here.
+    //
+    // Trade-off: we lose the explicit `VIDEO-RANGE=PQ` / `CODECS=
+    // dvh1.08.06` signaling on the master variant. AVPlayer has to
+    // infer Dolby Vision from the init segment's `dvh1` sample-entry
+    // FourCC, the `dvvC` configuration box, and the `colr` atom's
+    // BT.2020 + PQ primaries / transfer. Apple's HLS DV documentation
+    // recommends master-level signaling but doesn't require it for
+    // single-variant streams; the segment-level signaling alone is
+    // enough for the HDMI DV handshake on a capable TV (verified
+    // empirically on the next test cycle).
+    var masterCodecs: String? { nil }
+    var masterResolution: (width: Int, height: Int)? { nil }
+    var masterVideoRange: HLSVideoRange? { nil }
     var masterBandwidth: Int? { nil }
 }
 

Sources/aetherctl/main.swift

@@ -9,8 +9,16 @@
 // CLI lets us iterate locally.
 
 import Foundation
+import Darwin
 import AetherEngine
 
+// Disable stdout buffering so a `swift run aetherctl … > log.txt` or
+// `2>&1 | grep` pipeline sees engine prints in real time. Swift's
+// `print()` block-buffers when stdout isn't a tty, which masked the
+// engine's EngineLog output and only let FFmpeg's stderr through on
+// the first run.
+setbuf(stdout, nil)
+
 let args = CommandLine.arguments
 guard args.count >= 2 else {
     print("usage: aetherctl <url>")