AudioMixer new cmd: remove sample rate converter
Add a new command REMOVE to remove any sample rate converter
on a track, without having to delete the track name.
Add comments.
Remove some dead code.
Fix whitespace and comparison to NULL.
Change-Id: Id55a23ab5ee673189e99675b4e6fa5df7b617987
diff --git a/services/audioflinger/AudioMixer.cpp b/services/audioflinger/AudioMixer.cpp
index 05fa3b9..100f289 100644
--- a/services/audioflinger/AudioMixer.cpp
+++ b/services/audioflinger/AudioMixer.cpp
@@ -327,15 +327,9 @@
track.enabled = false;
invalidateState(1<<name);
}
- if (track.resampler != NULL) {
- // delete the resampler
- delete track.resampler;
- track.resampler = NULL;
- track.sampleRate = mSampleRate;
- invalidateState(1<<name);
- }
- track.volumeInc[0] = 0;
- track.volumeInc[1] = 0;
+ // delete the resampler
+ delete track.resampler;
+ track.resampler = NULL;
mTrackNames &= ~(1<<name);
}
@@ -439,6 +433,12 @@
track.resetResampler();
invalidateState(1 << name);
break;
+ case REMOVE:
+ delete track.resampler;
+ track.resampler = NULL;
+ track.sampleRate = mSampleRate;
+ invalidateState(1 << name);
+ break;
default:
LOG_FATAL("bad param");
}
@@ -499,7 +499,7 @@
bool AudioMixer::track_t::setResampler(uint32_t value, uint32_t devSampleRate)
{
- if (value!=devSampleRate || resampler) {
+ if (value != devSampleRate || resampler != NULL) {
if (sampleRate != value) {
sampleRate = value;
if (resampler == NULL) {
diff --git a/services/audioflinger/AudioMixer.h b/services/audioflinger/AudioMixer.h
index a04fe95..9698d0c 100644
--- a/services/audioflinger/AudioMixer.h
+++ b/services/audioflinger/AudioMixer.h
@@ -70,8 +70,17 @@
AUX_BUFFER = 0x4003,
DOWNMIX_TYPE = 0X4004,
// for target RESAMPLE
- SAMPLE_RATE = 0x4100,
- RESET = 0x4101,
+ SAMPLE_RATE = 0x4100, // Configure sample rate conversion on this track name;
+ // parameter 'value' is the new sample rate in Hz.
+ // Only creates a sample rate converter the first time that
+ // the track sample rate is different from the mix sample rate.
+ // If the new sample rate is the same as the mix sample rate,
+ // and a sample rate converter already exists,
+ // then the sample rate converter remains present but is a no-op.
+ RESET = 0x4101, // Reset sample rate converter without changing sample rate.
+ // This clears out the resampler's input buffer.
+ REMOVE = 0x4102, // Remove the sample rate converter on this track name;
+ // the track is restored to the mix sample rate.
// for target RAMP_VOLUME and VOLUME (8 channels max)
VOLUME0 = 0x4200,
VOLUME1 = 0x4201,
@@ -237,7 +246,10 @@
// indicates whether a downmix effect has been found and is usable by this mixer
static bool isMultichannelCapable;
+ // Call after changing either the enabled status of a track, or parameters of an enabled track.
+ // OK to call more often than that, but unnecessary.
void invalidateState(uint32_t mask);
+
static status_t prepareTrackForDownmix(track_t* pTrack, int trackNum);
static void track__genericResample(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);