enricobuehler
d5e23146c0
The ladder's last rung no longer runs FFmpeg. H.264 decodes through openh264, AV1 through rav1d, and HEVC is refused outright: no permissively licensed software HEVC decoder exists, so an HEVC session that exhausts its hardware rungs now tears down and re-dials advertising HEVC-less caps, and the host picks H.264. The plan calls that a first-class path; it is one. swscale is deleted, and with it the BT.601 default that its correction code existed to undo. Colour on the H.264 lane now comes from the same pf-bitstream planner every hardware rung submits from — openh264 reports no VUI at all — and AV1's comes per-picture from the sequence header. One colour source, one CSC: the old default is unrepresentable rather than merely fixed. Frames reach the presenter as three tightly-packed planes through the planar CSC pass, which had to be un-gated from the pyrowave feature and its device probe, since the last rung must exist on devices that failed that probe. rav1d rather than the dav1d crate, deliberately and against the plan's literal wording: dav1d-sys is system-deps-only, so it would add a system library and a .pc file to every client package — in the milestone family whose excision checklist exists to delete exactly that. rav1d is the same decoder, same licence, statically linked. The cost is honest: no-asm builds on both decoders, and software throughput is still unmeasured. The colour test is the milestone's exit criterion, so it is built to fail. Three fixtures, and a mutation check: hardcoding the swscale default turns the red bar to [255,24,0], and swapping Cb/Cr turns red to blue — a silent error no metadata assertion could catch. Review then disproved the range half of it numerically: with eight saturated bars, decoding the full-range fixture with the wrong range gives max error ZERO, because a mismatch only pushes values outside [0,1] where the shader clamps. A mid-tone was added; the wrong range now costs 11, well past the tolerance. The exit criterion I set was satisfiable by a test that proved nothing. Two blocking defects, both emergent rather than local. Software AV1 on a 10-bit stream never reached its typed refusal: rav1d is built 8-bit-only and returns ENOPROTOOPT, which the send loop turned into a generic error, so the pump's typed downcast missed and every AU failed identically — a permanent freeze on precisely the shipping case, since AV1 is advertised only where hardware AV1 exists and hardware AV1 plus HDR is Main 10. The shape is now read from the sequence header before any byte reaches the decoder, exactly as the H.264 leg reads the active SPS. And the new Reconnecting phase was the first state that is not streaming, not connecting, and still holding a live stream — which opened all three guards that had made a second launch impossible. Pressing A assigned over `stream` where every other site shuts down first, and StreamState has no Drop, so the old pump was detached: a second live session still submitting to a Vulkan device that gets destroyed underneath it. Nothing about the reconnect was wrong in isolation; the defect lived between a new state and three guards nobody re-examined. Start is now defensive and the retry raises the connecting modal, so the UI matches the state and B can cancel. Also closed: retry_caps was computed, tested and never applied, so a shape refusal could end a session reporting no codec available while a working retry existed; the retry inherited force_software sticky-true, landing an HEVC→H.264 fallback on software H.264 with working hardware H.264; it re-dialled with a stale mode; the CPU present arm had no survivable-failure handling where the pyrowave arm — same pass — has it; HEVC is no longer advertised when the decoder is pinned to software; and the software rung now feeds the recovery-point SEI it already had in hand to the re-anchor gate. ⚠ Two host-side gaps found while tracing, neither in scope here: Hello::launch is NOT idempotent (gog:/custom: targets spawn a second copy on a retry; the field is kept verbatim because dropping it orphans the gamescope display whose reuse key includes the command), and a reconnected session can never adopt a game predating its own launch stamp, so it has no game-exit detection. ⚠ OWED: the on-glass software run. ~200 lines of new Vulkan on a path that only runs because the GPU already failed, and no driver has seen it. The review's minimum check is sync validation enabled, a non-multiple-of-16 mode, a mid-session resize and demotion, and both colour matrices. Gates: container clippy -D warnings over four crates, 236 tests, workspace check. pf-vkdecode and pf-bitstream are byte-for-byte untouched, so the hardware rungs' 250/250 stands.
punktfunk — Android client (phone & TV)
The native Android app for streaming a punktfunk host to your phone, tablet, or Android TV. A Compose app that finds hosts on your network, pairs with a PIN, and streams at the display's own resolution — with hardware HEVC decode, HDR10, and controller support, built for both touch and the couch (D-pad / gamepad focus navigation).
Features
- Hardware decode — NDK
AMediaCodecHEVC →SurfaceView, including HDR10 (Main10 / BT.2020 PQ), with low-latency tuning and a live stats HUD. - Audio both ways — Opus + AAudio playback with a jitter ring, plus mic uplink to the host.
- Controller support — buttons + axes with rumble and HID feedback (lightbar / adaptive triggers); D-pad / gamepad focus navigation for TV and phone.
- Find hosts automatically — native mDNS discovery; first connect does a one-time SPAKE2 PIN pairing (or TOFU on trusted LANs), then reconnects on a Keystore-wrapped, pinned identity.
- Compose UI — Connect / Settings / Stream screens with Material You theming.
Built for arm64-v8a + armeabi-v7a + x86_64 — the 32-bit armeabi-v7a slice is what keeps the
app installable on the many 32-bit Google TV / Android TV streamers (Walmart onn. 4K, Chromecast with
Google TV, budget Amlogic boxes) that otherwise reject a 64-bit-only build as "not compatible".
Get it
Published to Google Play (Internal Testing) — join the beta via the Discord. Per-device setup and pairing: docs.punktfunk.unom.io/docs/install-client.
How it's built — Rust-heavy
Kotlin can't import the cbindgen C header the way Swift can, so a native bridge is unavoidable. We
write it in Rust and link punktfunk-core directly — so the Android client reuses the Linux
client's orchestration (audio jitter ring, VK keymap inverse, latency/skew math, capture state
machine, trust logic) instead of re-porting it into Kotlin.
| Side | Owns |
|---|---|
Rust (native/ → libpunktfunk_android.so) |
the JNI seam, NativeClient (QUIC control + UDP data plane), AnnexB → AMediaCodec decode (incl. HDR10), Opus + AAudio audio + mic, controller feedback, latency math, trust/pairing, mdns-sd discovery |
Kotlin (app/, kit/) |
Compose UI, SurfaceView lifecycle, input capture, the Wi-Fi MulticastLock + permission UX, Keystore identity |
The single seam is io.unom.punktfunk.kit.NativeBridge ⇄ Java_io_unom_punktfunk_kit_NativeBridge_*.
native/ Rust cdylib (workspace member) — links punktfunk-core directly
src/lib.rs crate doc · JNI_OnLoad · version probes
src/session/ session lifecycle: connect/pair + trust, plane start/stop, input shims
src/decode.rs AnnexB → AMediaCodec HEVC hardware decode → SurfaceView (incl. HDR10)
src/audio.rs · src/mic.rs Opus + AAudio playback / mic uplink
src/feedback.rs · src/stats.rs rumble + HID feedback; live video stats
src/discovery.rs native mdns-sd browse of the host's _punktfunk._udp advert
app/ :app — Compose UI: Connect / Settings / Stream (phone + TV)
kit/ :kit — NativeBridge · native mDNS discovery · Gamepad · Keymap · Keystore identity
Build & run
Prerequisites: Android SDK + NDK r30 (30.0.14904198), platforms;android-37.0,
build-tools;37.0.0, cmake;3.22.1 (builds libopus); JDK 21 (AGP 9.2 runs on JDK 17–21, not
a newer default); Rust with rustup target add aarch64-linux-android armv7-linux-androideabi x86_64-linux-android and
cargo install cargo-ndk. Toolchain is pinned (AGP 9.2 · Gradle 9.4.1 · Kotlin 2.3.21 · Compose BOM
2026.05.01 · compileSdk 37 · minSdk 28).
Android Studio: open clients/android — it uses its bundled JBR 21, and the cargoNdk* task
builds the .so as part of the normal build.
CLI (point Gradle at JDK 21 if your machine default is newer):
export JAVA_HOME="$(/usr/libexec/java_home -v 21)" # or your Temurin 21 path
cd clients/android
./gradlew :app:assembleDebug # cargo-ndk cross-compiles libpunktfunk_android.so first
./gradlew :app:installDebug # onto a running emulator/device
# emulators from env setup: emulator -avd pf_phone | emulator -avd pf_tv
The debug APK lands in app/build/outputs/apk/debug/. Launch it, pick a host, pair, and stream.
Related
- Documentation — quick start, pairing, troubleshooting
- Project README — the host, the other clients, and how it all fits together