visualizer: reset buffer if playback is idle
Visualizer capture buffer must be reset if audio framework has stopped
calling process for a given period of time to get read of residual
data from previous captures.
Issue 5571920.
Change-Id: I6e73f971bb812cdbb2979a3b5e763abab07634eb
diff --git a/media/libeffects/visualizer/EffectVisualizer.cpp b/media/libeffects/visualizer/EffectVisualizer.cpp
index 3c3af8f..1a06cc6 100644
--- a/media/libeffects/visualizer/EffectVisualizer.cpp
+++ b/media/libeffects/visualizer/EffectVisualizer.cpp
@@ -47,17 +47,22 @@
VISUALIZER_STATE_ACTIVE,
};
+// maximum number of reads from same buffer before resetting capture buffer. This means
+// that the framework has stopped playing audio and we must start returning silence
+#define MAX_STALL_COUNT 10
+
struct VisualizerContext {
const struct effect_interface_s *mItfe;
effect_config_t mConfig;
- uint32_t mState;
uint32_t mCaptureIdx;
uint32_t mCaptureSize;
- uint32_t mCurrentBuf;
+ uint8_t mState;
+ uint8_t mCurrentBuf;
+ uint8_t mLastBuf;
+ uint8_t mStallCount;
uint8_t mCaptureBuf[2][VISUALIZER_CAPTURE_SIZE_MAX];
};
-
//
//--- Local functions
//
@@ -66,6 +71,8 @@
{
pContext->mCaptureIdx = 0;
pContext->mCurrentBuf = 0;
+ pContext->mLastBuf = 1;
+ pContext->mStallCount = 0;
memset(pContext->mCaptureBuf[0], 0x80, VISUALIZER_CAPTURE_SIZE_MAX);
memset(pContext->mCaptureBuf[1], 0x80, VISUALIZER_CAPTURE_SIZE_MAX);
}
@@ -417,9 +424,24 @@
memcpy(pReplyData,
pContext->mCaptureBuf[pContext->mCurrentBuf ^ 1],
pContext->mCaptureSize);
+ // if audio framework has stopped playing audio although the effect is still
+ // active we must clear the capture buffer to return silence
+ if (pContext->mLastBuf == pContext->mCurrentBuf) {
+ if (pContext->mStallCount < MAX_STALL_COUNT) {
+ if (++pContext->mStallCount == MAX_STALL_COUNT) {
+ memset(pContext->mCaptureBuf[pContext->mCurrentBuf ^ 1],
+ 0x80,
+ pContext->mCaptureSize);
+ }
+ }
+ } else {
+ pContext->mStallCount = 0;
+ }
+ pContext->mLastBuf = pContext->mCurrentBuf;
} else {
memset(pReplyData, 0x80, pContext->mCaptureSize);
}
+
break;
default: