On Shield Experience 8.x (API 28) ExoPlayer force-decoded TrueHD to
multi-channel PCM, and enabling passthrough on the mpv backend made every
non-AAC file wedge on an infinite buffering spinner with no audio pipeline
at all.
Two defects behind one symptom pair:
- The MAT/DTS-HD carrier oracle stopped at API 29 because
AudioTrack.isDirectPlaybackSupported does not exist below it, so API 24-28
never offered the carrier even on routes that genuinely bitstream it. Below
API 29 the HDMI AudioDeviceInfo is the only vouching signal, so the carrier
is now offered when an HDMI output explicitly advertises IEC 61937 at
192kHz/8ch; unspecified (empty) capability arrays deliberately do not
count, because an unvouched IEC track that initialises without being
bitstreamed renders as full-scale noise. A route that advertises and still
refuses the track fails AudioTrack init into the existing force-decode
recovery.
- The mpv audio-spdif list was gated on the raw encodings the route
advertises, but mpv's audiotrack AO opens every spdif format as a stereo
ENCODING_IEC61937 track clamped to the 48kHz mixer rate. E-AC3, TrueHD and
DTS-HD MA structurally cannot survive that shape, and a route can advertise
raw encodings while its HAL takes no IEC track at all - naming any codec
there leaves mpv's audio chain stuck before AO init (reproduced on a Shield:
spdif_ac3 selected, no AudioTrack ever opened, playback never starts). The
list is now capped to ac3,dts and additionally gated on the route accepting
the stereo IEC shape, using the same tiered oracle as the carrier. The
primary mpv backend previously wrote a hardcoded five-codec list from Dart;
it now asks the plugin to derive the value from the audio route, like the
ExoPlayer fallback already did.
Verified on a Shield (API 30) with a full-capability EDID: TrueHD rides the
carrier and survives speed transitions (instrumentation), and an E-AC3 title
that previously wedged under mpv+passthrough now decodes and plays with
audio-spdif=ac3,dts.
close#1991
The rate-mismatch regression greps the audio diagnostics for the literal
'MAT/IEC 61937 carrier', but 658469f9 reworded the sink's engage message to
'TrueHD (MAT) via IEC 61937 carrier' when DTS-HD joined the carrier. The test
self-skips on carrier-less CI emulators, so the rot only surfaces on real
hardware, where the fallback behaves correctly and the assertion still fails.
Match the shared 'via IEC 61937 carrier' fragment both codecs emit.
Fire TV Stick 4K Max (and other Fire OS devices) advertise ENCODING_DTS_HD on
the HDMI route but only implement the DTS-HD basic profile, so media3's raw
path builds an AudioTrack that drains normally while the receiver hears
silence. The same routes do bitstream the 192kHz/7.1 ENCODING_IEC61937 carrier
TrueHD already rides, so DTS-HD MA access units are now packed into DTS type IV
bursts (a port of FFmpeg's spdif_header_dts4 at the 768kHz HD rate, the same
bytes Kodi's IEC packer produces) and played through that carrier.
The TrueHD MAT carrier sink is generalized into IecCarrierSink with one
IecCarrierPacker per codec. While the carrier route exists DTS-HD is binary -
the carrier or decoded PCM, never the lying raw path; routes without the
carrier keep the pre-carrier raw behavior. Master Audio peaks the carrier
cannot hold strip to the always-fitting core substream for ~60s, exactly as
FFmpeg does, and the packer output is pinned byte-for-byte against FFmpeg
spdif golden fixtures.
close#1988
Canary asserts stock media3 1.11.0 still reports these files unseekable
and snaps seeks to the start — when a media3 upgrade makes it fail, the
TrackAwareSeekMap repair in CuelessSeekExtractorWrapper can be retired.
The second test drives the production wrapper stack and requires the
seek to hold.
Carrier-or-decode gated the carrier on getDirectPlaybackSupport, which only
exists on API 33, so every older route force-decoded TrueHD - including
routes that bitstreamed it before the carrier existed. The #1863 Fire TV
Stick 4K Max is Fire OS 8 (API 30): its HDMI route advertises raw TrueHD
and IEC 61937 at 8 channels, 2.12.1 passed TrueHD through, and 2.13.0 hands
the same stream to the FFmpeg decoder. The Shield is API 30 as well.
API 29-32 now asks AudioTrack.isDirectPlaybackSupported about the exact
192kHz/7.1 IEC tuple before offering the carrier. It is coarser than the
API 33 probe - it cannot tell bitstream from offload - but an IEC 61937
track is PCM-shaped by definition, so direct support means the route
carries the frames. getMinBufferSize stays as the precondition on every
tier, and a route that still lies fails AudioTrack initialisation, which
the audio recovery path already answers by blocking direct output and
force-decoding in place. Below API 29 nothing can vouch for the tuple, so
the carrier is still not offered and TrueHD decodes as before.
The tier decision is split from the platform probes so it is unit-testable;
each probe is consulted only on the tiers where its API exists.
Selection reads Format.sampleRate, but the rate family is only certain once a
major sync is parsed. When a container announces the 48kHz family and the
bitstream announces 44.1kHz, the packer emits nothing: handleBuffer consumed the
input and reported success, so the stream played as silence for as long as it
lasted. TrueHdMatPacker.reset also left the flag latched, so every later stream
on that packer emitted nothing too.
Leave the offending access unit in the buffer, signal the capability change, and
let the decoder take the stream over. The packer clears the flag on reset.
The latch has to outlive both flush and reset. media3 resets every renderer
disabled by a new selection before enabling its replacement
(ExoPlayerImplInternal.enableRenderers), and both audio renderers share this
sink, so the outgoing renderer's reset arrives in the middle of the handover the
latch exists to cause; clearing it there loops straight back into the mismatch.
The real boundary is a new media item, which only ExoPlayerCore knows, so it
signals one before setting a new source. The same-item recovery, DV-mode and
subtitle reloads deliberately do not.
It is a generation rather than a flag because that hook runs on the app thread
while the mismatch is found on the playback thread: a late buffer from the
outgoing stream would otherwise disable the carrier for its successor.
Verified on the SEI Box R (Android 14, armv7) with a genuine 44.1kHz TrueHD
stream in a container patched to announce 48000, so the bitstream and its
checksums stay valid. The sink enters the carrier at 192kHz, reports the
mismatch, hands over to FFmpeg and plays on. The device test asserts that
sequence from the sink's own diagnostics, because the mismatch fires before the
carrier opens an AudioTrack and the rate sequence alone cannot distinguish it
from never having selected the carrier.
A bitstream cannot be resampled, so the carrier only ever accepts 1x. The
selection gate covered that, but nothing re-ran it: setPlaybackSpeed reaches
the sink and returns, and the renderer only re-asks when audio capabilities are
invalidated. A speed change during carrier playback therefore left the carrier
live and handed it parameters its empty processor chain cannot apply.
Signal the capability change from the sink, which reaches
onRendererCapabilitiesChanged and moves TrueHD onto the decoder; returning to
1x re-offers the carrier, so a speed nudge no longer costs Atmos for the rest
of the session. The carrier delegate is never given a non-1x speed while that
selection is in flight.
Report the requested parameters rather than the delegate's while the carrier is
active. The player polls the sink through the media clock and adopts what it
reads, so reporting the pinned 1x pushed it back into the player and silently
undid the speed change.
Rebuilding the track selector parameters is not an alternative:
DefaultTrackSelector skips invalidation when the rebuilt parameters compare
equal, so a forced reselection can silently no-op.
Verified on the SEI Box R (Android 14, armv7): carrier at 192kHz with no
decoder, speed to 1.5x moves it to the FFmpeg decoder at 48kHz with the clock
advancing faster than real time, and returning to 1x restores the carrier. The
device test skips itself on hardware that never takes the carrier, as the
Nvidia Shield does.
Android Automotive tells an app when the car requires distraction optimization,
and Plezy never asked. A monitor now watches CarUxRestrictions and publishes the
verdict over the existing platform channel, where a single Dart gate answers
whether playback may start.
The car service is reached through the lifecycle-listener overload rather than
Car.createCar(Context). That overload blocks its caller for up to five seconds
polling ServiceManager, and on car-service death it reaches killClient(), which
kills the hosting process for any context that is not an Activity or a Service -
a crash in a system component would take the app down with it. Head units on
Android 9 and 10 predate the listener, so a legacy ServiceConnection is used
there, with the same identity guard on reconnect.
A vehicle that has not answered yet counts as restricted, and one deadline is
spent resolving it rather than one per request, so a wedged car service delays
playback once instead of on every open.
The #1790 fix turns on an invariant no JVM fake can observe: `DefaultAudioSink`
charges a static, process-wide counter per flush and discharges it only from
`Listener::onReleased`, and any lasting imbalance stops media3 escalating audio
failures at all. The wrapper tests pin the wrapper's side of that contract
against a fake; nothing checked it against a real sink.
`onAudioTrackInitialized` fires once per acquisition and `onAudioTrackReleased`
once per answered flush, both on the public `AnalyticsListener`, so counting them
across the cycles the reuse cache actually creates measures the counter directly
without reaching into media3 internals. Seeking repeatedly exercises the
park-and-reuse path; switching to a fixture with a different channel count forces
the eviction path.
On a Shield with the pre-fix wrapper this reports initialized=5, released=0 after
four seeks — the counter climbing once per seek in a live session, which is the
state that makes a later AudioTrack failure unrecoverable.
A second case runs the same measurement on a bitstream route, which is the output
that failed on the reporter's device. It probes the live route the way the app
does and skips when there is no encoded surround, so a phone or a TV set to PCM
does not report coverage it never had.
Plex sidecar subtitles are attached as MediaItem.SubtitleConfiguration and
tagged `external_<n>`, then recovered from the Format id the track selector
reports. Since media3 1.3.0, DefaultMediaSourceFactory always merges
side-loaded subtitles with the primary source and MergingMediaPeriod rewrites
every child format id to "<periodIndex>:<originalId>", so the tag arrives as
"1:external_0" - measured on device - or "0:1:external_0" behind the
container-sidecar merge. The prefix test therefore never matched and every
sidecar reached Dart as an embedded track with no URI.
A Plex sidecar's only identity is its stream key, which the app carries in
that URI, so both matchers failed on it: a server-selected sidecar could
never resolve and left subtitle selection pending, and a manually chosen one
could not be mapped back to a stream id to write to the server. The
already-attached branch of addSubtitleTrack compared the raw id too, so
re-selecting a loaded sidecar silently did nothing.
Route every write and readback of the tag through ExternalSubtitleIds, which
matches the final id segment, and cover it with an instrumentation test that
side-loads a subtitle through the real media3 media-source factory. Also stop
claiming a saved track selection when no server stream was identified - there
is no local store, so that path silently dropped the user's choice.
close#1713
R8 only ever ran on `release`, so every automated gate in this repository
exercised code the shipped APK does not contain. Reflective lookups, JNI
callbacks and native library loading can all break under shrinking while
`flutter test`, the Robolectric suites and `connectedDebugAndroidTest`
stay green — which is exactly how #1703 shipped, with the bundled FFmpeg
audio renderer shrunk out of release builds for TrueHD and DTS-HD.
Add a `minified` build type that inherits release's shrinker
configuration but stays debuggable and debug-signed, so it is an ordinary
test artifact and never a publishable one. Three integration details
took a run each to find: the Flutter plugin copies app build types into
every plugin module, so library-level shrinking deleted the plugin entry
points that only GeneratedPluginRegistrant references; the harness must
not be shrunk or the runner disappears; and androidx.test has to survive
in the app under test, or the runner cannot link its own supertype and
the run reports zero tests instead of failing.
Instrumentation still defaults to `debug`, because only one build type
can host androidTest and the existing playback suites drive media3
builder APIs the app never calls, which R8 shrinks legitimately. The new
reachability test opts into the minified variant instead and touches no
builder API, so the only keeps it depends on are the ones under test.
Emptying proguard-rules.pro was verified to fail it.
edde746