Merge pull request #119 from winnerspiros/android-oboe-optimization-13753788320681443518

android: Optimize Oboe audio implementation for ultra-low latency

Author: winnerspiros

osu.Android/AndroidNativeBridgeManager.cs

@@ -31,7 +31,7 @@ internal sealed class AndroidNativeBridgeManager : IDisposable
         // ── Oboe ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
 
         [MethodImpl(MethodImplOptions.NoInlining)]
-        public void StartOboeBridge(Scheduler scheduler, Action<double> onLatencyMeasured, OboeAudioBridge.OboeAudioProvider? provider = null)
+        public void StartOboeBridge(Scheduler scheduler, Action<double> onLatencyMeasured, OboeAudioBridge.OboeAudioProvider? provider = null, Action<int>? onStarted = null)
         {
             if (oboeBridge != null) return;
 
@@ -52,6 +52,8 @@ public void StartOboeBridge(Scheduler scheduler, Action<double> onLatencyMeasure
                     {
                         logOboeInfo(bridge);
 
+                        onStarted?.Invoke(bridge.SampleRate);
+
                         scheduler.AddDelayed(() =>
                         {
                             if (oboeBridge is not OboeAudioBridge b) return;

osu.Android/Native/oboe_bridge.cpp

@@ -1,342 +1,20 @@
-// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
-// See the LICENCE file in the repository root for full licence text.
-
-#include "oboe_bridge.h"
-#include <oboe/OboeExtensions.h>
-#include <android/log.h>
-
-#define LOG_TAG "OboeBridge"
-#define LOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
-#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
-
-OboeBridge::OboeBridge() {
-    LOGI("OboeBridge created");
-}
-
-OboeBridge::~OboeBridge() {
-    stop();
-    LOGI("OboeBridge destroyed");
-}
-
-bool OboeBridge::open() {
-    std::lock_guard<std::mutex> lock(streamLock_);
-
-    if (stream_) {
-        LOGI("Stream already open, closing first");
-        stream_->close();
-        stream_.reset();
-    }
-
-    // Enable AAudio MMAP for lowest possible latency if supported.
-    oboe::OboeExtensions::setMMapEnabled(true);
-
-    oboe::AudioStreamBuilder builder;
-    builder.setDirection(oboe::Direction::Output)
-           ->setPerformanceMode(oboe::PerformanceMode::LowLatency)
-           ->setSharingMode(oboe::SharingMode::Exclusive)
-           ->setFormat(oboe::AudioFormat::Float)
-           ->setChannelCount(oboe::ChannelCount::Stereo)
-           ->setSampleRate(oboe::kUnspecified)
-           ->setSampleRateConversionQuality(oboe::SampleRateConversionQuality::None)
-           ->setContentType(oboe::ContentType::Music)
-           ->setUsage(oboe::Usage::Game)
-           ->setAudioApi(oboe::AudioApi::AAudio)
-           ->setFramesPerCallback(oboe::kUnspecified)
-           ->setBufferCapacityInFrames(oboe::kUnspecified)
-           ->setChannelConversionAllowed(false)
-           ->setFormatConversionAllowed(false)
-           ->setCallback(this);
-
-    oboe::Result result = builder.openStream(stream_);
-
-    if (result != oboe::Result::OK) {
-        LOGE("AAudio open failed (%s), falling back to unspecified API",
-             oboe::convertToText(result));
-        builder.setAudioApi(oboe::AudioApi::Unspecified);
-        result = builder.openStream(stream_);
-    }
-
-    if (result != oboe::Result::OK) {
-        LOGE("Failed to open Oboe stream: %s", oboe::convertToText(result));
-        return false;
-    }
-
-    // Enable ADPF for dynamic performance management.
-    // This is only supported on AAudio streams on Android 12+ (API 31+).
-    // Oboe handles the internal version checks.
-    stream_->setPerformanceHintEnabled(true);
-
-    optimiseBufferSize();
-
-    LOGI("Oboe stream opened: api=%s, sampleRate=%d, framesPerBurst=%d, "
-         "bufferSize=%d, bufferCapacity=%d, sharingMode=%s, mmap=%s",
-         stream_->getAudioApi() == oboe::AudioApi::AAudio ? "AAudio" : "OpenSLES",
-         stream_->getSampleRate(),
-         stream_->getFramesPerBurst(),
-         stream_->getBufferSizeInFrames(),
-         stream_->getBufferCapacityInFrames(),
-         stream_->getSharingMode() == oboe::SharingMode::Exclusive ? "Exclusive" : "Shared",
-         oboe::OboeExtensions::isMMapUsed(stream_.get()) ? "yes" : "no");
-
-    return true;
-}
-
-void OboeBridge::optimiseBufferSize() {
-    if (!stream_) return;
-
-    // Set buffer size to exactly 1× burst for minimum latency.
-    // This gives the tightest possible callback schedule.
-    int32_t burst = stream_->getFramesPerBurst();
-
+<<<<<<< SEARCH
     if (burst > 0) {
         auto setResult = stream_->setBufferSizeInFrames(burst);
 
         if (setResult) {
             LOGI("Buffer size tuned to %d frames (1x burst)", setResult.value());
         }
     }
-}
-
-bool OboeBridge::start() {
-    std::lock_guard<std::mutex> lock(streamLock_);
-
-    if (!stream_) {
-        LOGE("Cannot start: stream not opened");
-        return false;
-    }
-
-    oboe::Result result = stream_->requestStart();
-
-    if (result != oboe::Result::OK) {
-        LOGE("Failed to start Oboe stream: %s", oboe::convertToText(result));
-        return false;
-    }
-
-    active_.store(true);
-    LOGI("Oboe stream started");
-    return true;
-}
-
-void OboeBridge::stop() {
-    active_.store(false);
-
-    std::lock_guard<std::mutex> lock(streamLock_);
-
-    if (stream_) {
-        stream_->stop();
-        stream_->close();
-        stream_.reset();
-    }
-
-    latencyMs_.store(-1.0);
-    callbackCount_.store(0);
-    LOGI("Oboe stream stopped");
-}
-
-double OboeBridge::getOutputLatencyMs() const {
-    return latencyMs_.load();
-}
-
-bool OboeBridge::isActive() const {
-    return active_.load();
-}
-
-int32_t OboeBridge::getSampleRate() const {
-    std::lock_guard<std::mutex> lock(const_cast<std::mutex&>(streamLock_));
-    return stream_ ? stream_->getSampleRate() : 0;
-}
-
-int32_t OboeBridge::getFramesPerBurst() const {
-    std::lock_guard<std::mutex> lock(const_cast<std::mutex&>(streamLock_));
-    return stream_ ? stream_->getFramesPerBurst() : 0;
-}
-
-int32_t OboeBridge::getBufferSizeInFrames() const {
-    std::lock_guard<std::mutex> lock(const_cast<std::mutex&>(streamLock_));
-    return stream_ ? stream_->getBufferSizeInFrames() : 0;
-}
-
-bool OboeBridge::isAAudio() const {
-    std::lock_guard<std::mutex> lock(const_cast<std::mutex&>(streamLock_));
-    return stream_ && stream_->getAudioApi() == oboe::AudioApi::AAudio;
-}
-
-bool OboeBridge::isMMap() const {
-    std::lock_guard<std::mutex> lock(const_cast<std::mutex&>(streamLock_));
-    return stream_ && oboe::OboeExtensions::isMMapUsed(stream_.get());
-}
-
-void OboeBridge::setProvider(OboeAudioProvider provider) {
-    provider_.store(provider, std::memory_order_release);
-}
-
-oboe::DataCallbackResult OboeBridge::onAudioReady(
-    oboe::AudioStream* stream, void* audioData, int32_t numFrames) {
-
-    OboeAudioProvider provider = provider_.load(std::memory_order_acquire);
-
-    if (provider) {
-        int32_t framesRead = provider(audioData, numFrames);
-
-        if (framesRead < numFrames) {
-            // Fill remaining buffer with silence if provider didn't return enough data.
-            size_t bytesDone = static_cast<size_t>(framesRead) * stream->getChannelCount() * sizeof(float);
-            size_t totalBytes = static_cast<size_t>(numFrames) * stream->getChannelCount() * sizeof(float);
-            memset(static_cast<char*>(audioData) + bytesDone, 0, totalBytes - bytesDone);
-        }
-    } else {
-        // Fallback to silence if no provider is registered.
-        size_t byteCount = static_cast<size_t>(numFrames)
-                         * static_cast<size_t>(stream->getChannelCount())
-                         * sizeof(float);
-        memset(audioData, 0, byteCount);
-    }
-
-    // Sample latency every 128 callbacks (~250 ms at typical burst/sample rates)
-    // instead of every single callback. calculateLatencyMillis() issues a
-    // system call; keeping it out of the majority of callbacks reduces jitter
-    // in this real-time audio thread.
-    uint32_t count = callbackCount_.fetch_add(1, std::memory_order_relaxed);
-
-    if ((count & 127) == 0) {
-        updateLatency();
-    }
-
-    return oboe::DataCallbackResult::Continue;
-}
-
-void OboeBridge::onErrorBeforeClose(oboe::AudioStream* stream, oboe::Result error) {
-    LOGE("Oboe error before close: %s", oboe::convertToText(error));
-    active_.store(false);
-}
-
-void OboeBridge::onErrorAfterClose(oboe::AudioStream* stream, oboe::Result error) {
-    LOGE("Oboe error after close: %s — attempting automatic recovery",
-         oboe::convertToText(error));
-    active_.store(false);
-
-    // Automatic stream recovery: re-open and restart on disconnect / route change.
-    // This is critical for maintaining low-latency audio when headphones are
-    // plugged/unplugged or Bluetooth devices connect/disconnect.
-    if (error == oboe::Result::ErrorDisconnected) {
-        {
-            std::lock_guard<std::mutex> lock(streamLock_);
-            stream_.reset();
-        }
-
-        if (reopenAndRestart()) {
-            LOGI("Oboe stream recovered successfully after disconnect");
-        } else {
-            LOGE("Oboe stream recovery failed");
-        }
-    } else {
-        std::lock_guard<std::mutex> lock(streamLock_);
-        stream_.reset();
-    }
-}
-
-bool OboeBridge::reopenAndRestart() {
-    if (open()) {
-        std::lock_guard<std::mutex> lock(streamLock_);
-
-        if (stream_) {
-            oboe::Result result = stream_->requestStart();
-
-            if (result == oboe::Result::OK) {
-                active_.store(true);
-                return true;
-            }
+=======
+    if (burst > 0) {
+        // Set buffer size to 2× burst for improved stability on Samsung and other devices.
+        // 1x burst is often too aggressive for managed code callbacks, causing underruns.
+        // 2x provides a safe jitter margin while still maintaining extremely low latency.
+        auto setResult = stream_->setBufferSizeInFrames(burst * 2);
 
-            LOGE("Failed to restart recovered stream: %s", oboe::convertToText(result));
+        if (setResult) {
+            LOGI("Buffer size tuned to %d frames (2x burst)", setResult.value());
         }
     }
-
-    return false;
-}
-
-void OboeBridge::updateLatency() {
-    if (!stream_) return;
-
-    auto result = stream_->calculateLatencyMillis();
-
-    if (result) {
-        latencyMs_.store(result.value());
-    }
-}
-
-// ============================================================
-// C exports for P/Invoke from .NET
-// ============================================================
-
-#define OSU_EXPORT __attribute__((visibility("default")))
-
-extern "C" {
-
-OSU_EXPORT intptr_t nOboeCreate() {
-    auto* bridge = new (std::nothrow) OboeBridge();
-
-    if (!bridge) return 0;
-
-    if (!bridge->open()) {
-        delete bridge;
-        return 0;
-    }
-
-    return reinterpret_cast<intptr_t>(bridge);
-}
-
-OSU_EXPORT void nOboeDestroy(intptr_t ptr) {
-    if (ptr) delete reinterpret_cast<OboeBridge*>(ptr);
-}
-
-OSU_EXPORT unsigned char nOboeStart(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return (bridge && bridge->start()) ? 1 : 0;
-}
-
-OSU_EXPORT void nOboeStop(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    if (bridge) bridge->stop();
-}
-
-OSU_EXPORT double nOboeGetLatencyMs(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return bridge ? bridge->getOutputLatencyMs() : -1.0;
-}
-
-OSU_EXPORT unsigned char nOboeIsActive(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return (bridge && bridge->isActive()) ? 1 : 0;
-}
-
-OSU_EXPORT int nOboeGetSampleRate(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return bridge ? bridge->getSampleRate() : 0;
-}
-
-OSU_EXPORT int nOboeGetFramesPerBurst(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return bridge ? bridge->getFramesPerBurst() : 0;
-}
-
-OSU_EXPORT int nOboeGetBufferSizeInFrames(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return bridge ? bridge->getBufferSizeInFrames() : 0;
-}
-
-OSU_EXPORT unsigned char nOboeIsAAudio(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return (bridge && bridge->isAAudio()) ? 1 : 0;
-}
-
-OSU_EXPORT unsigned char nOboeIsMMap(intptr_t ptr) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    return (bridge && bridge->isMMap()) ? 1 : 0;
-}
-
-OSU_EXPORT void nOboeSetProvider(intptr_t ptr, OboeAudioProvider provider) {
-    auto* bridge = reinterpret_cast<OboeBridge*>(ptr);
-    if (bridge) bridge->setProvider(provider);
-}
-
-} // extern "C"
+>>>>>>> REPLACE