BluetoothAudio: Refine the FMQ size for A2DP software encoding
For those high-resolution codecs, they are 24 or 32 bits per sample, so
the buffer size must be the LCM of 16, 24, and 32.
Bug: 194980528
Test: A2DP playing with aptX and / or LDAC
Change-Id: I788e185496dea4a1b40fa369e032a4f8491b835b
diff --git a/bluetooth/audio/2.0/default/A2dpSoftwareAudioProvider.cpp b/bluetooth/audio/2.0/default/A2dpSoftwareAudioProvider.cpp
index f71a73e..0c0b85f 100644
--- a/bluetooth/audio/2.0/default/A2dpSoftwareAudioProvider.cpp
+++ b/bluetooth/audio/2.0/default/A2dpSoftwareAudioProvider.cpp
@@ -32,10 +32,14 @@
using ::android::bluetooth::audio::BluetoothAudioSessionReport;
using ::android::hardware::Void;
+// Here the buffer size is based on SBC
static constexpr uint32_t kPcmFrameSize = 4; // 16 bits per sample / stereo
-static constexpr uint32_t kPcmFrameCount = 128;
+// SBC is 128, and here choose the LCM of 16, 24, and 32
+static constexpr uint32_t kPcmFrameCount = 96;
static constexpr uint32_t kRtpFrameSize = kPcmFrameSize * kPcmFrameCount;
-static constexpr uint32_t kRtpFrameCount = 7; // max counts by 1 tick (20ms)
+// The max counts by 1 tick (20ms) for SBC is about 7. Since using 96 for the
+// PCM counts, here we just choose a greater number
+static constexpr uint32_t kRtpFrameCount = 10;
static constexpr uint32_t kBufferSize = kRtpFrameSize * kRtpFrameCount;
static constexpr uint32_t kBufferCount = 2; // double buffer
static constexpr uint32_t kDataMqSize = kBufferSize * kBufferCount;
diff --git a/bluetooth/audio/2.1/default/A2dpSoftwareAudioProvider.cpp b/bluetooth/audio/2.1/default/A2dpSoftwareAudioProvider.cpp
index a37176b..4928cea 100644
--- a/bluetooth/audio/2.1/default/A2dpSoftwareAudioProvider.cpp
+++ b/bluetooth/audio/2.1/default/A2dpSoftwareAudioProvider.cpp
@@ -34,10 +34,14 @@
using ::android::hardware::Void;
using ::android::hardware::bluetooth::audio::V2_0::AudioConfiguration;
+// Here the buffer size is based on SBC
static constexpr uint32_t kPcmFrameSize = 4; // 16 bits per sample / stereo
-static constexpr uint32_t kPcmFrameCount = 128;
+// SBC is 128, and here we choose the LCM of 16, 24, and 32
+static constexpr uint32_t kPcmFrameCount = 96;
static constexpr uint32_t kRtpFrameSize = kPcmFrameSize * kPcmFrameCount;
-static constexpr uint32_t kRtpFrameCount = 7; // max counts by 1 tick (20ms)
+// The max counts by 1 tick (20ms) for SBC is about 7. Since using 96 for the
+// PCM counts, here we just choose a greater number
+static constexpr uint32_t kRtpFrameCount = 10;
static constexpr uint32_t kBufferSize = kRtpFrameSize * kRtpFrameCount;
static constexpr uint32_t kBufferCount = 2; // double buffer
static constexpr uint32_t kDataMqSize = kBufferSize * kBufferCount;