Take latency and current time into account for visualization

Buffer more data, and return the data that is currently being
output from the audio output, to ensure that visualizations are
smooth and responsive even when the audio output has a large
latency and/or large buffers.
b/6522728

Change-Id: I401637f01be7600b3c594a55c869036c13b206c0

1 files changed, 29 insertions, 0 deletions

diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 2cfc3e8..e7ababa 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -1818,6 +1818,10 @@ uint32_t AudioFlinger::PlaybackThread::correctLatency(uint32_t latency) const
 uint32_t AudioFlinger::PlaybackThread::latency() const
 {
     Mutex::Autolock _l(mLock);
+    return latency_l();
+}
+uint32_t AudioFlinger::PlaybackThread::latency_l() const
+{
     if (initCheck() == NO_ERROR) {
         return correctLatency(mOutput->stream->get_latency(mOutput->stream));
     } else {
@@ -8187,6 +8191,31 @@ status_t AudioFlinger::EffectModule::configure()
         status = cmdStatus;
     }
 
+    if (status == 0 &&
+            (memcmp(&mDescriptor.type, SL_IID_VISUALIZATION, sizeof(effect_uuid_t)) == 0)) {
+        uint32_t buf32[sizeof(effect_param_t) / sizeof(uint32_t) + 2];
+        effect_param_t *p = (effect_param_t *)buf32;
+
+        p->psize = sizeof(uint32_t);
+        p->vsize = sizeof(uint32_t);
+        size = sizeof(int);
+        *(int32_t *)p->data = VISUALIZER_PARAM_LATENCY;
+
+        uint32_t latency = 0;
+        PlaybackThread *pbt = thread->mAudioFlinger->checkPlaybackThread_l(thread->mId);
+        if (pbt != NULL) {
+            latency = pbt->latency_l();
+        }
+
+        *((int32_t *)p->data + 1)= latency;
+        (*mEffectInterface)->command(mEffectInterface,
+                                     EFFECT_CMD_SET_PARAM,
+                                     sizeof(effect_param_t) + 8,
+                                     &buf32,
+                                     &size,
+                                     &cmdStatus);
+    }
+
     mMaxDisableWaitCnt = (MAX_DISABLE_TIME_MS * mConfig.outputCfg.samplingRate) /
             (1000 * mConfig.outputCfg.buffer.frameCount);