Add enabling variable for extended precision audio
Set AudioFlinger::kEnableExtendedPrecision = true to enable
extended precision. Enabling will be required for devices (such as
USB) which report 24 bit or 32 bit sink formats.
Change-Id: I0dc1d7a4f7607086d7b536ea0e43aef0e696f2ee
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 527fd65..11a01cc 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -1621,6 +1621,19 @@
mHardwareStatus = AUDIO_HW_OUTPUT_OPEN;
audio_stream_out_t *outStream = NULL;
+
+ // FOR TESTING ONLY:
+ // Enable increased sink precision for mixing mode if kEnableExtendedPrecision is true.
+ if (kEnableExtendedPrecision && // Check only for Normal Mixing mode
+ !(flags & (AUDIO_OUTPUT_FLAG_COMPRESS_OFFLOAD | AUDIO_OUTPUT_FLAG_DIRECT))) {
+ // Update format
+ //config.format = AUDIO_FORMAT_PCM_FLOAT;
+ //config.format = AUDIO_FORMAT_PCM_24_BIT_PACKED;
+ //config.format = AUDIO_FORMAT_PCM_32_BIT;
+ //config.format = AUDIO_FORMAT_PCM_8_24_BIT;
+ // ALOGV("openOutput() upgrading format to %#08x", config.format);
+ }
+
status_t status = hwDevHal->open_output_stream(hwDevHal,
id,
*pDevices,
@@ -1644,9 +1657,9 @@
if (flags & AUDIO_OUTPUT_FLAG_COMPRESS_OFFLOAD) {
thread = new OffloadThread(this, output, id, *pDevices);
ALOGV("openOutput() created offload output: ID %d thread %p", id, thread);
- } else if ((flags & AUDIO_OUTPUT_FLAG_DIRECT) ||
- (config.format != AUDIO_FORMAT_PCM_16_BIT) ||
- (config.channel_mask != AUDIO_CHANNEL_OUT_STEREO)) {
+ } else if ((flags & AUDIO_OUTPUT_FLAG_DIRECT)
+ || !isValidPcmSinkFormat(config.format)
+ || (config.channel_mask != AUDIO_CHANNEL_OUT_STEREO)) {
thread = new DirectOutputThread(this, output, id, *pDevices);
ALOGV("openOutput() created direct output: ID %d thread %p", id, thread);
} else {
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 6e73a14..ddc6afb 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -326,6 +326,24 @@
audio_devices_t devices);
void purgeStaleEffects_l();
+ // Set kEnableExtendedPrecision to true to use extended precision in MixerThread
+ static const bool kEnableExtendedPrecision = false;
+
+ // Returns true if format is permitted for the PCM sink in the MixerThread
+ static inline bool isValidPcmSinkFormat(audio_format_t format) {
+ switch (format) {
+ case AUDIO_FORMAT_PCM_16_BIT:
+ return true;
+ case AUDIO_FORMAT_PCM_FLOAT:
+ case AUDIO_FORMAT_PCM_24_BIT_PACKED:
+ case AUDIO_FORMAT_PCM_32_BIT:
+ case AUDIO_FORMAT_PCM_8_24_BIT:
+ return kEnableExtendedPrecision;
+ default:
+ return false;
+ }
+ }
+
// standby delay for MIXER and DUPLICATING playback threads is read from property
// ro.audio.flinger_standbytime_ms or defaults to kDefaultStandbyTimeInNsecs
static nsecs_t mStandbyTimeInNsecs;
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index d6390b1..792d722 100755
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -1157,12 +1157,12 @@
type_t type)
: ThreadBase(audioFlinger, id, device, AUDIO_DEVICE_NONE, type),
mNormalFrameCount(0), mSinkBuffer(NULL),
- mMixerBufferEnabled(false),
+ mMixerBufferEnabled(AudioFlinger::kEnableExtendedPrecision),
mMixerBuffer(NULL),
mMixerBufferSize(0),
mMixerBufferFormat(AUDIO_FORMAT_INVALID),
mMixerBufferValid(false),
- mEffectBufferEnabled(false),
+ mEffectBufferEnabled(AudioFlinger::kEnableExtendedPrecision),
mEffectBuffer(NULL),
mEffectBufferSize(0),
mEffectBufferFormat(AUDIO_FORMAT_INVALID),
@@ -1401,9 +1401,10 @@
frameCount, mFrameCount);
} else {
ALOGV("AUDIO_OUTPUT_FLAG_FAST denied: isTimed=%d sharedBuffer=%p frameCount=%d "
- "mFrameCount=%d format=%d isLinear=%d channelMask=%#x sampleRate=%u mSampleRate=%u "
+ "mFrameCount=%d format=%#x mFormat=%#x isLinear=%d channelMask=%#x "
+ "sampleRate=%u mSampleRate=%u "
"hasFastMixer=%d tid=%d fastTrackAvailMask=%#x",
- isTimed, sharedBuffer.get(), frameCount, mFrameCount, format,
+ isTimed, sharedBuffer.get(), frameCount, mFrameCount, format, mFormat,
audio_is_linear_pcm(format),
channelMask, sampleRate, mSampleRate, hasFastMixer(), tid, mFastTrackAvailMask);
*flags &= ~IAudioFlinger::TRACK_FAST;
@@ -1809,9 +1810,10 @@
if (!audio_is_valid_format(mFormat)) {
LOG_ALWAYS_FATAL("HAL format %#x not valid for output", mFormat);
}
- if ((mType == MIXER || mType == DUPLICATING) && mFormat != AUDIO_FORMAT_PCM_16_BIT) {
- LOG_ALWAYS_FATAL("HAL format %#x not supported for mixed output; "
- "must be AUDIO_FORMAT_PCM_16_BIT", mFormat);
+ if ((mType == MIXER || mType == DUPLICATING)
+ && !isValidPcmSinkFormat(mFormat)) {
+ LOG_FATAL("HAL format %#x not supported for mixed output",
+ mFormat);
}
mFrameSize = audio_stream_frame_size(&mOutput->stream->common);
mBufferSize = mOutput->stream->common.get_buffer_size(&mOutput->stream->common);